Imaging

findings

in

noncraniofacial

childhood

rhabdomyosarcoma

Rhabdomyosarcoma

-LRB-

RMS

-RRB-

is

the

most

common

soft-tissue

sarcoma

of

childhood

This

paper

is

focuses

on

imaging

for

diagnosis

staging

and

follow-up

of

noncraniofacial

RMS

Introduction

Rhabdomyosarcoma

-LRB-

RMS

-RRB-

is

the

most

common

paediatric

soft-tissue

sarcoma

and

constitutes

of

all

malignancies

in

childhood

-LSB-

-RSB-

In

children

the

age-standardized

annual

incidence

rate

for

RMS

is

between

and

per

million

-LSB-

-RSB-

This

review

focuses

on

the

imaging

of

all

RMS

occurring

outside

the

head

and

neck

region

which

comprise

of

RMS

around

are

genitourinary

-LRB-

GU

-RRB-

nonbladder

prostate

tumours

-LRB-

GU-NBP

i.e.

paratesticular

vaginal

and

uterine

tumours

-RRB-

are

bladder

prostate

tumours

-LRB-

BP

-RRB-

occur

in

the

limbs

and

occur

in

other

sites

-LRB-

i.e.

thoracic

or

abdominal

tumours

-RRB-

Clinical

symptoms

vary

widely

based

on

the

location

of

the

primary

tumour

but

in

general

presenting

symptoms

often

are

indolent

with

nonspecific

or

minimal

symptoms

at

the

start

mimicking

innocent

general

paediatric

diseases

Often

the

duration

or

progression

of

symptoms

alerts

the

physician

to

the

presence

of

a

malignant

tumour

Site-specific

symptoms

in

GU-NBP

tumours

are

a

paratesticular

mass

in

boys

that

may

be

painful

or

not

while

girls

may

present

with

a

grape-like

-LRB-

botryoid

-RRB-

vaginal

extrusion

of

mucosanguineous

tissue

or

micturition

problems

BP

tumours

may

present

with

urinary

retention

haematuria

constipation

or

an

abdominal

mass

Limb

tumours

often

present

with

a

painless

swelling

and/or

with

enlarged

regional

lymph

nodes

while

presentation

of

tumours

in

other

locations

may

vary

from

biliary

obstruction

in

tumours

of

the

biliary

tract

to

painless

masses

all

depending

on

their

primary

site

Patients

with

metastatic

disease

present

with

more

general

symptoms

of

fatigue

weight

loss

and

low

blood

counts

As

soon

as

a

RMS

is

suspected

an

extensive

work-up

must

be

performed

to

get

a

histological

diagnosis

and

correct

staging

of

the

tumour

Imaging

of

the

primary

site

with

US

MRI

or

CT

is

required

in

all

patients

at

the

start

of

the

diagnostic

work-up

-LSB-

-RSB-

Once

the

diagnosis

has

been

confirmed

histologically

the

most

frequently

involved

metastatic

sites

will

be

investigated

CT

of

the

lungs

imaging

of

regional

lymph

nodes

and

a

technetium

bone

scan

are

recommended

for

every

patient

Furthermore

bone

marrow

aspirates

and

trephines

should

be

performed

in

all

patients

while

examination

of

the

cerebral

spinal

fluid

is

only

required

in

patients

with

paraspinal

and

parameningeal

locations

As

soon

as

the

work-up

has

been

completed

the

patient

can

be

stratified

to

receive

treatment

according

to

the

child

's

risk

group

based

on

the

six

significant

prognostic

factors

for

localized

RMS

that

came

out

of

a

retrospective

European

analysis

-LRB-

European

Paediatric

Soft-tissue

Sarcoma

Study

Group

EpSSG

-RRB-

histology

postsurgical

status

according

to

the

Intergroup

Rhabdomyosarcoma

Study

Group

-LRB-

IRSG

-RRB-

tumour

site

node

involvement

tumour

size

and

patient

age

-LRB-

Table

-RRB-

Table

prognostic

factors

-LSB-

-RSB-

FavourableUnfavourableHistologyEmbryonalAlveolarIRSG

statusHigher

grades

more

unfavourableTumour

siteHead

and

neck

non-parameningealAll

other

sitesOrbitalGenitourinary

nonbladder/prostateNode

size

-LRB-

cm

-RRB-

-LRB-

years

-RRB-

Pathology

RMS

is

a

fast-growing

primitive

high-grade

malignant

mesenchymal

tumour

Depending

on

their

degree

of

differentiation

the

tumour

cells

manifest

features

that

more

or

less

can

be

found

in

the

cells

of

skeletal

muscle

These

features

essential

for

the

diagnosis

are

the

presence

of

myofibrils

and

cross

striations

-LRB-

on

light

and

electron

microscopy

-RRB-

and/or

positive

immunohistochemical

staining

for

markers

of

muscle

differentiation

such

as

desmin

and

For

detailed

descriptions

of

the

histopathological

aspects

of

RMS

reference

should

be

made

to

Weiss

and

Goldblum

-LSB-

-RSB-

and

Fletcher

et

al.

-LSB-

-RSB-

Based

on

morphology

RMS

is

traditionally

subdivided

into

embryonal

alveolar

and

pleomorphic

Pleomorphic

RMS

in

contrast

to

embryonal

and

alveolar

RMS

almost

exclusively

occurs

in

adults

-LRB-

median

age

sixth

decade

-RRB-

and

is

therefore

not

discussed

further

Embryonal

RMS

is

the

most

common

type

-LRB-

of

all

RMS

-RRB-

The

cells

show

a

close

resemblance

to

various

stages

in

the

embryogenesis

of

normal

skeletal

muscle

-LRB-

Fig.

-RRB-

Subtypes

are

botryoid

RMS

and

spindle-cell

RMS

-LRB-

Fig.

-RRB-

When

arising

in

the

submucosa

embryonal

RMS

may

present

as

a

fast-growing

exophytic

polypoid

mass

This

macroscopic

variant

is

called

botryoid

RMS

-LRB-

grape-like

-RRB-

and

due

to

its

growth

pattern

-LRB-

primary

exophytic

and

not

invasive

-RRB-

has

a

better

prognosis

Fig.

RMS

small

cells

and

primitive

spindle-shaped

cells

resembling

the

first

stages

of

developing

normal

skeletal

muscle

-LRB-

H&E

original

magnification

-RRB-

Fig.

RMS

spindle-cell

type

closely

packed

spindle

cells

arranged

in

perpendicular

crossing

fascicles

giving

a

leiomyosarcoma-like

appearance

-LRB-

H&E

original

magnification

-RRB-

Spindle-cell

RMS

comprising

about

of

all

RMS

seems

to

behave

less

aggressively

and

is

most

often

encountered

in

a

paratesticular

location

-LRB-

about

of

all

paratesticular

RMS

-RRB-

and

the

head

and

neck

-LSB-

-RSB-

Histologically

spindle

cell

RMS

is

characterized

by

parallel

orientation

of

spindle

cells

with

an

eosinophilic

fibrillary

cytoplasm

and

an

elongated

hyperchromatic

nucleus

The

cells

are

arranged

in

broad

fascicles

-LRB-

fibro

leiomyosarcoma-like

-RRB-

or

in

short

interdigitating

fascicles

-LRB-

storiform

-RRB-

and

whirls

with

in

contrast

to

the

broad

fasciculated

variant

-LRB-

leiomyomatous

type

-RRB-

an

abundant

partly

hyalinized

collagenous

matrix

Alveolar

RMS

is

composed

of

ill-defined

dense

aggregates

of

poorly

differentiated

round

or

oval

tumour

cells

that

frequently

show

loss

of

cohesion

-LRB-

Fig.

-RRB-

This

loss

of

cohesion

and

the

presence

of

thin

fibrous

septa

result

in

an

alveolar

pattern

In

cases

where

the

tumour

cells

do

not

show

loss

of

cohesion

the

term

solid

alveolar

RMS

is

used

Alveolar

RMS

represents

about

of

all

RMS

and

has

two

specific

translocations

with

specific

fusion

transcripts

that

can

be

detected

by

RT-PCR

The

majority

-LRB-

about

-RRB-

show

a

t

-LRB-

-RRB-

-LRB-

-RRB-

translocation

with

the

corresponding

fusion

transcript

-LSB-

-RSB-

In

about

a

t

-LRB-

-RRB-

-LRB-

-RRB-

translocation

is

found

with

fusion

transcript

In

rare

cases

RMS

with

a

more

or

less

alveolar

pattern

lacks

these

translocations

Fig.

RMS

cluster

of

primitive

cells

with

loss

of

cellular

cohesion

and

bordered

by

dense

fibrous

septa

resulting

in

an

alveolar

pattern

-LRB-

H&E

original

magnification

-RRB-

Both

embryonal

and

alveolar

RMS

may

show

rhabdoid

tumour-like

features

and

anaplasia

-LRB-

focal

or

diffuse

-RRB-

-LSB-

-RSB-

More

recently

under

the

heading

sclerosing

RMS

a

variant

with

hyalin

sclerosis

has

been

described

-LRB-

Fig.

-RRB-

-LSB-

-RSB-

It

is

unclear

whether

this

is

a

distinct

subtype

Fig.

RMS

small

cells

primitive

spindle-shaped

cells

and

eosinophilic

rhabdomyoblasts

in

a

background

of

hyaline

sclerosis

-LRB-

H&E

original

magnification

-RRB-

In

the

IRSG

and

the

International

Society

of

Paediatric

Oncology

-LRB-

SIOP

-RRB-

suggested

a

prognostically

more

significant

classification

-LRB-

Table

-RRB-

-LSB-

-RSB-

Table

IRSG

and

SIOP

classification

extended

with

new

variants

-LSB-

-RSB-

GroupPrognosisSubtypeIBetter

prognosisEmbryonal

RMS

botryoid

typeEmbryonal

RMS

spindle-cell

typeIIIntermediate

prognosisEmbryonal

RMS

-LRB-

remaining

-RRB-

IIIWorse

prognosisAlveolar

RMSIVUnclear

prognosisRMS

with

rhabdoid

featuresEmbryonal

RMS

with

diffuse

anaplasiaSclerosing

RMS

Imaging

findings

Radiography

As

RMS

is

a

soft-tissue

tumour

conventional

radiology

plays

an

insignificant

role

in

its

diagnosis

Localized

bony

erosion

adjacent

to

the

primary

site

is

a

recognized

complication

this

area

may

be

hot

on

a

bone

scan

in

the

absence

of

metastatic

disease

in

the

skeleton

In

contrast

to

the

initial

diagnostic

work-up

where

for

the

assessment

of

pulmonary

metastases

CT

is

mandatory

AP

and

lateral

chest

radiographs

are

used

in

the

follow-up

period

Ultrasonography

US

is

often

the

first

imaging

modality

used

in

children

with

soft-tissue

masses

because

it

is

readily

available

has

high

resolution

and

can

easily

assess

extent

and

vascularity

of

a

mass

One

should

not

forget

that

most

soft-tissue

lesions

are

benign

can

readily

be

diagnosed

with

US

and

do

not

need

further

diagnostic

work-up

or

even

treatment

On

US

RMS

in

general

shows

as

a

well-defined

slightly

hypoechoic

inhomogeneous

mass

that

can

show

significantly

increased

flow

-LRB-

Fig.

-RRB-

In

the

particular

case

of

paratesticular

RMS

US

is

the

imaging

modality

of

choice

although

CT

of

the

abdomen

is

also

necessary

to

evaluate

for

retroperitoneal

lymphadenopathy

In

all

other

RMS

locations

additional

imaging

using

CT

or

MRI

is

mandatory

Fig.

boy

with

a

mass

in

the

left

scrotum

US

image

shows

an

ill-defined

heterogeneous

mass

surrounding

the

testis

-LRB-

open

arrow

-RRB-

The

mass

shows

increased

flow

-LRB-

solid

arrow

-RRB-

Histopathology

embryonal

RMS

US

is

also

of

use

in

image-guided

biopsies

Recently

Sebire

and

Roebuck

-LSB-

-RSB-

systematically

reviewed

the

pathological

diagnosis

of

paediatric

tumours

from

image-guided

needle-core

biopsies

They

concluded

that

image-guided

biopsy

material

was

sufficient

to

come

to

a

diagnosis

in

-LRB-

CI

-RRB-

of

patients

Complications

needing

treatment

mostly

haemorrhage

requiring

transfusion

were

reported

in

only

of

patients

For

image-guided

biopsies

the

material

obtained

should

be

transported

fresh

to

the

pathology

department

Fixation

should

not

be

performed

as

this

precludes

further

cytogenetic

studies

CT

In

order

to

assess

pulmonary

metastases

from

RMS

CT

of

the

chest

is

a

mandatory

examination

However

assessment

of

pulmonary

involvement

can

sometimes

be

difficult

Although

criteria

such

as

number

and

size

of

lesions

morphology

-LRB-

noncalcified

round

and

well-defined

-RRB-

and

location

-LRB-

inferior

lobes

subpleural

spaces

branching

vessels

-RRB-

have

been

applied

in

adult

patients

has

shown

specificity

According

to

the

EpSSG

guidelines

for

evaluating

chest

CT

the

following

criteria

with

respect

to

the

diagnosis

of

pulmonary

metastases

should

be

applied

one

pulmonary

or

one

pleural

nodule

over

mm

in

diameter

two

or

more

well-defined

nodules

of

mm

or

five

or

more

lesions

mm

-LSB-

-RSB-

This

comes

with

the

assumption

that

there

is

no

other

medical

explanation

for

these

lesions

When

there

is

a

high

suspicion

that

a

small

lesion

is

metastatic

and

appears

to

be

the

only

site

of

metastatic

disease

biopsy

may

be

performed

In

the

EpSSG

protocol

lung

biopsy

is

not

recommended

With

the

introduction

of

multidetector

CT

-LRB-

MDCT

-RRB-

the

advantage

of

MRI

of

being

a

multiplanar

imaging

modality

has

been

overtaken

and

by

virtue

of

its

underlying

physics

CT

is

superior

to

MRI

in

detecting

osseous

changes

The

drawback

of

CT

in

children

is

the

use

of

ionizing

radiation

Since

the

seminal

papers

of

Paterson

et

al.

-LSB-

-RSB-

and

Brenner

et

al.

-LSB-

-RSB-

we

should

be

aware

of

the

theoretical

risk

of

CT-induced

cancer

fatalities

and

take

this

into

consideration

especially

in

the

work-up

of

children

with

cancer

as

they

have

already

proven

their

tendency

to

present

with

a

malignancy

early

in

life

-LSB-

-RSB-

MRI

With

its

superior

ability

to

depict

soft-tissue

changes

MRI

is

the

primary

imaging

modality

in

RMS

-LSB-

-RSB-

Although

imaging

protocols

should

be

tailored

for

each

individual

patient

they

should

at

least

consist

of

axial

and

images

-LRB-

for

anatomic

detail

and

assessment

of

neurovascular

structures

-RRB-

images

perpendicular

to

the

axial

plane

and

imaging

after

gadolinium

administration

It

is

important

that

at

least

two

series

should

be

identical

one

before

and

one

after

contrast

agent

administration

to

be

able

to

discern

enhancement

Contrast-enhanced

series

are

mandatory

and

ideally

be

performed

with

fat

saturation

The

imaging

characteristics

of

RMS

are

relatively

nonspecific

Like

most

soft-tissue

tumours

they

have

intermediate

signal

intensity

on

images

-LRB-

Fig.

-RRB-

On

images

they

tend

to

be

of

intermediate-to-high

signal

intensity

If

the

tumour

contains

a

high

number

of

septa

it

may

have

a

lobular

shape

RMS

in

general

show

strong

enhancement

on

postcontrast

imaging

-LRB-

Fig.

-RRB-

In

very

rare

instances

the

tumour

may

show

a

predominantly

cystic

appearance

-LRB-

Fig.

-RRB-

Dynamic

series

are

useful

in

order

to

assess

tumour

vascularity

and

to

differentiate

between

postchemotherapy/surgery

residual

disease

and

fibrosis

Fig.

girl

who

noticed

a

small

lump

near

the

anus

a

MR

image

shows

a

well-defined

pararectal

lesion

-LRB-

arrow

-RRB-

b

After

intravenous

gadolinium

administration

the

lesion

shows

homogeneous

enhancement

-LRB-

arrow

-RRB-

Histopathology

alveolar

RMSFig

girl

with

haemolysis

fever

and

a

mass

underneath

the

scapula

a

Coronal

STIR

image

shows

a

lesion

with

mixed

signal

intensity

-LRB-

open

arrow

-RRB-

and

multiple

enlarged

lymph

nodes

in

the

neck

-LRB-

solid

arrow

-RRB-

b

Axial

image

shows

multiple

cystic

lesions

with

fluid-fluid

levels

-LRB-

open

arrow

-RRB-

Histopathology

stage

IV

embryonal

RMS

For

the

surgeon

in

order

to

plan

surgery

it

is

of

importance

to

describe

the

compartment

in

which

the

RMS

is

located

-LSB-

-RSB-

Vascular

involvement

is

considered

to

be

absent

if

there

is

a

normal

tissue

plane

visible

between

the

tumour

and

the

vessel

or

if

the

tumour

has

a

less

then

a

circumferential

relationship

If

the

tumour

surrounds

the

vessel

for

more

than

it

is

considered

to

be

encased

Two

studies

have

addressed

the

use

of

whole-body

MRI

-LRB-

WB-MRI

-RRB-

in

paediatric

oncology

-LSB-

-RSB-

In

the

first

study

with

various

malignant

tumours

WB-MRI

had

a

superior

positive

predictive

value

for

skeletal

metastases

compared

to

bone

scintigraphy

-LRB-

vs.

respectively

-RRB-

and

also

a

significantly

higher

sensitivity

-LRB-

vs.

respectively

-RRB-

-LSB-

-RSB-

In

the

second

study

WB-MRI

had

a

higher

sensitivity

-LRB-

-RRB-

than

skeletal

scintigraphy

-LRB-

-RRB-

for

the

detection

of

bone

marrow

metastases

but

a

lower

sensitivity

than

FDG-PET

-LRB-

-RRB-

-LSB-

-RSB-

The

authors

of

both

studies

concluded

that

WB-MRI

can

replace

bone

scintigraphy

One

advantage

of

this

approach

would

be

the

implementation

of

a

one-stop-shop

approach

to

childhood

RMS

A

drawback

of

MRI

in

young

children

is

however

the

need

for

general

anaesthesia

Bone

scintigraphy

In

the

current

EpSSG

protocols

bone

scintigraphy

is

mandatory

as

part

of

the

work-up

in

patients

with

RMS

The

finding

of

an

isolated

hot

spot

on

the

bone

scan

should

be

evaluated

with

conventional

radiography

or

MRI

Cogswell

et

al.

-LSB-

-RSB-

reported

a

retrospective

series

of

primarily

adult

patients

with

RMS

and

found

bone

metastases

in

Bone

scintigraphy

in

their

study

had

a

sensitivity

of

and

specificity

in

the

detection

of

metastatic

disease

In

contrast

to

this

in

a

Dutch

study

of

patients

with

soft-tissue

sarcoma

bone

metastases

were

found

in

only

patients

-LRB-

-RRB-

-LSB-

-RSB-

However

of

these

eight

patients

six

reported

bone

pain

and

all

had

other

sites

of

metastatic

disease

The

authors

conclude

that

the

yield

of

routine

bone

scintigraphy

is

low

and

that

it

should

be

reserved

for

symptomatic

or

high-risk

patients

only

Positron

emission

tomography-CT

In

PET-CT

studies

fluorodeoxyglucose

-LRB-

-RRB-

a

radiolabelled

glucose

analogue

is

used

-LSB-

-RSB-

As

is

a

glucose

analogue

it

shows

uptake

in

metabolically

active

cells

which

most

malignant

tumour

cells

are

The

combination

of

PET

with

CT

without

moving

the

relative

position

of

the

patient

yields

a

higher

diagnostic

accuracy

than

PET

alone

-LRB-

Fig.

-RRB-

In

general

the

CT

scan

will

be

low-dose

CT

scan

only

meant

to

identify

anatomical

structures

However

as

the

CT

scanners

in

modern

PET-CT

systems

are

of

high

diagnostic

quality

it

is

also

possible

to

combine

a

diagnostic

CT

scan

e.g.

for

the

depiction

of

pulmonary

metastases

with

a

PET

scan

Fig.

boy

with

a

history

of

treated

metastatic

RMS

presented

with

low

back

pain

The

PET-CT

image

shows

intense

uptake

in

the

spinal

canal

-LRB-

open

arrow

-RRB-

Physiological

excretion

of

the

radiopharmaceutical

via

the

kidneys

is

visible

-LRB-

solid

arrows

-RRB-

Histopathology

embryonal

RMS

The

literature

on

the

use

of

PET-CT

in

children

with

RMS

is

limited

to

several

case

reports

or

small

studies

-LSB-

-RSB-

Although

in

some

cases

PET-CT

has

been

shown

to

be

of

benefit

in

individual

patients

larger

prospective

studies

are

needed

Staging

and

follow-up

Staging

of

RMS

is

of

importance

for

the

individual

patient

as

it

gives

an

indication

of

prognosis

and

thus

treatment

stratification

From

a

broader

perspective

staging

makes

compiling

data

on

larger

patient

groups

for

research

purposes

possible

enabling

evaluation

of

the

outcome

of

different

treatment

regimens

The

main

staging

system

is

the

postsurgical

staging

system

developed

by

the

IRSG

This

is

currently

used

by

study

groups

both

in

the

USA

and

now

in

Europe

also

-LRB-

Table

-RRB-

The

IRSG

was

formed

in

and

consisted

of

surgeons

pathologists

oncologists

and

radiation

oncologists

The

absence

of

radiologists

is

striking

and

paediatric

radiologists

are

still

infrequently

involved

in

development

of

paediatric

oncology

study

protocols

although

in

the

EpSSG

RMS

paediatric

radiologists

were

involved

in

the

development

of

the

protocol

For

staging

regional

nodes

it

is

important

to

be

familiar

with

the

regional

node

stations

Lymph

node

involvement

has

a

negative

impact

on

prognosis

as

has

been

shown

in

the

SIOP

Malignant

Mesenchymal

Tumor

trial

-LSB-

-RSB-

Overall

survival

was

for

patients

versus

in

patients

-LRB-

P

-RRB-

Distant

lymph

node

involvement

upgrades

a

patient

to

stage

IV

disease

-LRB-

Fig.

-RRB-

having

an

adverse

impact

on

prognosis

overall

survival

becomes

-LSB-

-RSB-

Table

classificationStageCharacteristicsILocalized

disease

completely

resected

-LRB-

regional

nodes

not

involved

-RRB-

A

Tumour

confined

to

muscle

or

organ

of

originB

Tumour

infiltrating

outside

organ

of

-LRB-

muscle

of

-RRB-

originIILocalized

or

regional

disease

with

total

resection

of

gross

tumourA

Primary

tumour

grossly

resected

with

microscopic

residual

disease

-LRB-

negative

findings

in

local

nodes

-RRB-

B

Primary

tumour

and

positive

nodes

completely

resectedC

Primary

tumour

and

positive

nodes

resected

with

evidence

of

microscopic

residual

diseaseIIIIncomplete

resection

of

tumour

or

biopsy

with

gross

residual

diseaseIVDistant

metastatic

disease

present

at

diagnosis

Table

lists

the

regional

node

stations

by

primary

tumour

site

Oval-shape

lymph

nodes

and

a

short

axis

cm

are

considered

to

be

normal

-LSB-

-RSB-

If

the

node

shows

peripheral

enhancement

or

is

round

with

a

short

axis

of

cm

then

the

node

should

be

considered

probably

invaded

by

tumour

Besides

surgical

resection

or

needle-core

biopsies

lymph

node

involvement

can

also

be

assessed

using

fine-needle

aspiration

-LRB-

FNA

-RRB-

Klijanienko

et

al.

-LSB-

-RSB-

reported

a

review

of

the

use

of

FNA

in

tumours

-LRB-

-RRB-

were

either

diagnosed

accurately

or

as

round-cell

sarcoma

Table

node

stations

by

primary

tumour

site

Disease

with

involvement

of

other

lymph

nodes

than

those

specified

in

the

table

should

be

classified

as

stage

IVAnatomical

siteNode

stationExtremityLower

extremityInguinal

femoral

popliteal

nodes

-LRB-

rare

-RRB-

Upper

extremityAxillary

brachial

epitrochlear

and

infraclavicular

nodesGenitourinaryBladder

prostate

cervix

uterus

paratesticularPelvic

retroperitoneal

nodes

at

renal

artery

level

or

belowVaginaRetroperitoneal

pelvic

nodes

at

or

below

common

iliac

inguinal

nodes

VulvaInguinal

nodesThoracicIntrathoracicInternal

mammary

mediastinal

nodesRetroperitoneum/pelvisPelvic

retroperitoneal

nodesTrunkAbdominal

wallInguinal

femoral

nodesChest

wallAxillary

internal

mammary

and

infraclavicular

nodesOtherBiliaryLiver

hilar

nodes

Perianal/perinealInguinal

pelvic

nodes

-LRB-

may

be

bilateral

-RRB-

Only

in

patients

with

intraspinal

or

suspected

meningeal

extension

-LRB-

on

imaging

or

clinical

assessment

-RRB-

does

the

EpSSG

RMS

protocol

state

that

craniospinal

MR

should

also

be

performed

In

the

current

EpSSG

RMS

protocol

risk

stratification

is

based

on

six

criteria

that

have

emerged

from

the

analyses

of

previous

European

studies

histology

-LRB-

embryonal

vs.

alveolar

-RRB-

postsurgical

stage

-LRB-

IRSG

-RRB-

tumour

site

node

stage

tumour

size

and

patient

age

-LRB-

Table

-RRB-

-LSB-

-RSB-

During

follow-up

tumour

size

is

an

important

parameter

in

assessing

tumour

response

In

the

current

EpSSG

protocol

complete

remission

is

defined

as

disappearance

of

tumour

both

clinically

and

on

imaging

Minor

response

is

defined

as

reduction

in

volume

after

three

courses

of

chemotherapy

if

not

reached

the

patient

is

eligible

for

second-line

chemotherapy

In

recording

tumour

response

the

EpSSG

uses

volumetric

evaluation

additionally

the

presence

or

absence

of

a

posttherapeutic

residue

should

be

mentioned

in

the

radiology

report

-LSB-

-RSB-

In

studies

in

adults

the

use

of

Response

Evaluation

Criteria

In

Solid

Tumours

-LRB-

RECIST

-RRB-

has

been

advocated

by

the

European

Organization

for

Research

and

Treatment

of

Cancer

-LRB-

EORTC

-RRB-

National

Cancer

Institute

of

Canada

Clinical

Trials

Group

and

the

National

Cancer

Institute

-LRB-

NCI

-RRB-

of

the

United

States

-LSB-

-RSB-

With

respect

to

implementation

in

children

RECIST

have

been

a

matter

of

debate

-LSB-

-RSB-

Recently

RECIST

were

retrospectively

applied

to

ten

consecutive

children

with

cancer

-LSB-

-RSB-

The

authors

concluded

that

tumour

size

was

underestimated

and

that

in

disseminated

disease

many

lesions

were

either

calcified

or

too

small

to

measure

and

therefore

that

RECIST

are

not

readily

applicable

in

paediatric

oncology

Currently

the

EpSSG

has

incorporated

RECIST

to

be

used

alongside

the

volumetric

measurements

in

their

latest

protocol

in

order

to

prospectively

assess

the

validity

of

RECIST

in

a

large

patient

population

with

a

single

tumour

type

Tumour

relapse

in

patients

most

commonly

presents

with

locoregional

disease

-LRB-

-RRB-

compared

to

distant

relapse

-LRB-

-RRB-

-LSB-

-RSB-

-LRB-

Fig.

-RRB-

In

a

retrospective

case-based

study

the

use

of

PET-CT

was

advocated

this

however

needs

to

be

evaluated

in

larger

prospective

studies

-LSB-

-RSB-

Fig.

years

after

initial

diagnosis

the

patient

shown

in

Fig.

presented

at

the

outpatient

clinic

complaining

of

back

pain

a

Coronal

STIR

image

of

the

pelvis

shows

discrete

increased

signal

intensity

in

the

left

ischium

-LRB-

open

arrow

-RRB-

b

Subsequently

acquired

PET-CT

image

confirms

the

presence

of

recurrent

disease

in

the

same

location

-LRB-

open

arrow

-RRB-

Note

excretion

of

tracer

into

the

urinary

bladder

-LRB-

solid

arrow

-RRB-

c

PET-CT

image

also

shows

a

second

lesion

in

the

thoracic

spine

-LRB-

open

arrow

-RRB-

Additional

rib

and

pleural

metastases

were

also

visible

-LRB-

not

visible

on

this

image

-RRB-

Tumour

locations

Genitourinary

Approximately

of

all

RMS

are

GU

RMS

-LSB-

-RSB-

As

mentioned

above

GU

RMS

can

simply

be

subdivided

into

two

subgroups

based

on

different

prognosis

and

subsequent

treatment

strategy

GU

bladder/prostate

-LRB-

GU-BP

-RRB-

being

an

unfavourable

location

-LRB-

Fig.

-RRB-

Tumours

at

other

GU

non-bladder/prostate

-LRB-

GU-NBP

-RRB-

sites

such

as

a

paratesticular

location

-LRB-

testes

epididymis

and

spermatic

cord

Fig.

-RRB-

vagina

or

uterus

-LRB-

Fig.

-RRB-

have

a

favourable

prognosis

and

thus

require

less-intensive

treatment

-LSB-

-RSB-

There

is

a

caveat

to

MRI

of

the

bladder

in

RMS

after

intravenous

contrast

medium

administration

layering

of

contrast

medium

can

occur

making

it

difficult

to

appreciate

bladder

wall

enhancement

-LSB-

-RSB-

sequences

can

be

particularly

useful

in

this

setting

to

assess

bladder

wall

thickening

Additional

cystoscopy

is

often

warranted

-LSB-

-RSB-

At

the

end

of

treatment

some

residual

soft-tissue

thickening

may

persist

and

on

MRI

it

is

impossible

to

decide

whether

this

is

residual

scarring

or

tumour

in

these

cases

endoscopic

biopsy

is

mandatory

Fig.

boy

with

RMS

of

the

prostate

The

sagittal

contrast-enhanced

MR

image

shows

the

lesion

invading

the

bladder

wall

A

transurethral

catheter

has

been

inserted

-LRB-

open

arrow

-RRB-

Histopathology

botryoid

RMSFig

girl

presented

with

a

mass

in

the

vagina

a

Axial

contrast-enhanced

image

shows

the

mass

with

heterogeneous

enhancement

The

tumour

has

both

solid

-LRB-

asterisk

-RRB-

and

fluid

-LRB-

open

arrow

-RRB-

compartments

b

Sagittal

MR

image

shows

the

mass

with

mixed

signal

intensity

The

bladder

is

displaced

anteriorly

and

the

uterus

can

not

be

visualized

Histopathology

embryonal

RMS

Extremities

RMS

of

the

extremities

-LRB-

Figs.

and

-RRB-

is

almost

always

of

alveolar

histology

tends

to

occur

in

older

children

and

young

adults

is

often

present

with

positive

regional

lymph

nodes

and

has

a

propensity

to

metastasize

to

unusual

sites

these

negative

prognostic

factors

contribute

to

the

relatively

poor

prognosis

of

RMS

in

this

location

-LSB-

-RSB-

In

approximately

of

patients

nodal

involvement

is

seen

on

imaging

however

when

nodal

dissection

is

performed

the

rate

of

nodal

involvement

increases

to

almost

-LSB-

-RSB-

This

discrepancy

between

imaging

findings

and

nodal

dissection

might

be

reduced

by

using

high-quality

state-of-the-art

US

In

current

treatment

protocols

systematic

biopsy

of

regional

nodes

is

advocated

even

if

the

nodes

are

not

palpable

or

enlarged

on

imaging

sentinel

node

procedures

are

recommended

whenever

feasible

although

the

value

of

upgrading

a

patient

to

a

higher

risk

group

based

merely

on

a

positive

sentinel

node

has

not

been

studied

yet

As

in

all

tumours

of

the

extremities

preoperative

imaging

plays

a

vital

role

in

the

depiction

of

the

relationship

between

neurovascular

bundles

and

the

tumour

Fig.

girl

presenting

with

a

mass

in

the

left

lower

leg

a

Axial

contrast-enhanced

MR

image

shows

an

ill-defined

mass

circumferential

to

the

fibula

Note

the

cortical

thinning

-LRB-

open

arrow

-RRB-

of

the

fibula

b

Sagittal

PD-weighted

image

shows

diffuse

bone

marrow

metastases

Histopathology

embryonal

RMSFig

boy

with

a

mass

in

the

third

ray

of

the

left

foot

MR

image

shows

a

discrete

lesion

-LRB-

open

arrow

-RRB-

of

intermediate

signal

intensity

Histopathology

embryonal

RMS

Other

Chest

wall

Chest

wall

RMS

-LRB-

Fig.

-RRB-

is

a

relatively

rare

finding

with

a

reported

incidence

of

in

the

IRSG

II

and

IRSG

III

studies

-LSB-

-RSB-

Most

of

the

reports

of

chest

wall

involvement

are

either

case

reports

or

small

series

-LSB-

-RSB-

In

a

retrospective

analysis

of

patients

Saenz

et

al.

-LSB-

-RSB-

found

a

survival

of

Fig.

boy

presenting

with

a

mass

on

the

right

chest

wall

a

US

image

shows

a

heterogeneous

mass

in

the

pectoralis

major

muscle

-LRB-

the

pectoralis

minor

is

not

involved

asterisk

-RRB-

b

MR

image

of

the

chest

shows

a

mass

of

intermediate

signal

intensity

c

After

intravenous

contrast

medium

administration

the

lesion

shows

homogeneous

enhancement

Histopathology

alveolar

RMS

Pulmonary

There

is

an

ongoing

debate

and

controversy

whether

congenital

cystic

anomalies

predispose

children

to

intralesional

development

of

RMS

-LSB-

-RSB-

It

has

been

reported

that

pleuropulmonary

blastoma

-LRB-

PPB

-RRB-

has

been

mistaken

for

or

classified

as

RMS

arising

in

congenital

cystic

adenomatoid

malformation

-LRB-

CCAM

-RRB-

on

a

number

of

occasions

-LSB-

-RSB-

Despite

the

fact

that

the

exact

incidence

in

CCAM

is

unknown

it

has

prompted

paediatric

surgeons

to

resect

even

small

pulmonary

cystic

lesions

-LRB-

Fig.

-RRB-

-LSB-

-RSB-

Fig.

boy

with

dyspnoea

Chest

CT

image

shows

displacement

of

the

trachea

-LRB-

open

arrow

-RRB-

and

oesophagus

-LRB-

solid

arrow

-RRB-

to

the

right

due

to

a

large

mass

-LRB-

asterisk

-RRB-

with

accompanying

pleural

effusion

Histopathology

embryonal

RMS

Biliary

tree

RMS

is

the

most

common

tumour

of

the

biliary

tree

in

childhood

although

it

only

accounts

for

approximately

of

all

childhood

tumours

-LSB-

-RSB-

The

initial

diagnosis

will

in

most

patients

be

made

on

US

which

may

show

a

solid

or

cystic

mass

situated

in

the

liver

hilum

and

intrahepatic

bile

duct

dilatation

-LRB-

Fig.

-RRB-

MRI

is

mandatory

for

presurgical

evaluation

where

magnetic

resonance

cholangiopancreatography

-LRB-

MRCP

-RRB-

can

depict

the

biliary

tree

-LRB-

Fig.

-RRB-

In

many

patients

however

endoscopic

retrograde

cholangiopancreatography

-LRB-

ERCP

-RRB-

will

have

to

be

performed

in

order

to

depict

intraductal

irregularities

-LRB-

Fig.

-RRB-

Biliary

tree

RMS

is

a

tumour

that

does

not

necessarily

need

to

be

fully

resected

in

order

to

achieve

long-term

survival

as

long

as

adequate

radiotherapy

is

added

-LSB-

-RSB-

Intraperitoneal

metastases

which

can

also

be

found

on

follow-up

should

also

be

born

in

mind

Fig.

boy

presented

with

abdominal

pain

and

jaundice

a

US

image

shows

a

central

process

in

the

liver

hilum

-LRB-

open

arrow

-RRB-

and

dilatation

of

the

intrahepatic

bile

ducts

-LRB-

solid

arrow

-RRB-

b

MR

image

shows

a

circumscribed

lesion

with

increased

signal

intensity

-LRB-

open

arrow

-RRB-

c

MRCP

image

shows

intrahepatic

bile

duct

dilatation

Note

that

the

right

and

left

duct

systems

do

not

communicate

-LRB-

open

arrow

-RRB-

d

ERCP

image

-LRB-

ERCP

performed

in

order

to

insert

a

stent

in

the

common

bile

duct

-RRB-

Histopathology

embryonal

RMS

Other

locations

In

extremely

rare

instances

RMS

can

be

found

in

other

organs

such

as

the

heart

the

diaphragm

-LRB-

Fig.

-RRB-

the

omentum

the

urachus

and

the

digestive

tract

-LSB-

-RSB-

Fig.

boy

was

shown

to

have

a

right-sided

pleural

effusion

on

a

chest

radiograph

Balanced

FFE

sagittal

MR

image

shows

a

mass

-LRB-

open

arrow

-RRB-

arising

from

the

diaphragm

-LRB-

courtesy

of

S.G.F.

Robben

Academic

Hospital

Maastricht

The

Netherlands

-RRB-

Congenital

RMS

has

been

reported

to

occur

as

a

congenital

tumour

-LRB-

Fig.

-RRB-

-LSB-

-RSB-

In

congenital

alveolar

RMS

the

prognosis

is

reported

to

be

extremely

poor

despite

otherwise

adequate

treatment

-LSB-

-RSB-

Orbach

et

al.

-LSB-

-RSB-

reported

the

SIOP

data

on

soft-tissue

sarcoma

in

the

first

year

of

life

In

their

study

population

of

newborns

with

a

follow-up

of

years

out

of

newborns

with

RMS

survived

It

has

been

noted

that

in

congenital

RMS

the

disease

may

be

metastatic

at

the

time

of

birth

with

metastases

described

in

a

number

of

organs

and

in

the

placenta

-LSB-

-RSB-

Fig.

girl

born

with

a

lump

on

the

left

foot

Antenatal

ultrasonography

at

weeks

showed

no

abnormalities

a

MR

image

shows

a

large

inhomogeneous

mass

arising

from

the

left

foot

b

Abdominal

US

image

shows

popliteal

and

inguinal

nodal

invasion

and

hepatic

and

pancreatic

metastases

-LRB-

open

arrow

-RRB-

Due

to

the

poor

prognosis

no

therapy

was

given

and

the

child

died

several

weeks

later

Histopathology

poorly

differentiated

soft-tissue

sarcoma

without

distinct

translocations

Adult

patients

Every

once

in

a

while

paediatric

radiologists

and

paediatric

oncologists

receive

a

request

for

help

in

the

management

of

an

adult

patient

-LRB-

Fig.

-RRB-

RMS

although

seen

as

a

soft-tissue

tumour

of

childhood

can

also

occur

later

in

life

-LSB-

-RSB-

Compared

to

childhood

RMS

adult

RMS

has

a

poor

outcome

In

a

large

retrospective

study

of

patients

overall

survival

was

only

-LSB-

-RSB-

However

the

patients

in

this

series

treated

according

to

the

guidelines

for

treatment

of

childhood

RMS

showed

survival

figures

comparable

to

those

seen

in

children

This

suggests

that

treatment

of

adult

RMS

should

be

based

on

paediatric

protocols

tailored

to

adults

to

increase

survival

in

this

age

group

In

the

Academic

Medical

Centre

Amsterdam

we

have

a

working

group

on

childhood

tumours

in

-LRB-

often

young

-RRB-

adults

that

specifically

deals

with

this

challenging

population

This

working

group

consists

of

medical

oncologists

paediatric

oncologists

radiation

oncologists

-LRB-

orthopaedic

-RRB-

surgeons

and

a

paediatric

radiologist

Imaging

features

will

in

general

not

be

of

help

as

the

pretest

likelihood

of

RMS

in

an

adolescent

or

adult

is

extremely

low

Fig.

man

with

a

mass

in

the

thigh

contrast-enhanced

MR

image

shows

a

heterogeneous

circumscribed

mass

in

the

vastus

lateralis

muscle

of

the

right

leg

Histopathology

alveolar

RMS

Differential

diagnosis

Given

the

wide

variety

of

locations

in

which

RMS

can

be

found

it

is

difficult

to

give

a

concise

list

of

differential

diagnoses

The

site

of

the

primary

lesion

determines

the

differential

diagnosis

Keeping

location

out

of

the

equation

there

are

however

certain

tumours

such

as

haemangiomas/vascular

malformations

-LRB-

Fig.

-RRB-

adult-type

soft-tissue

sarcomas

peripheral

neuroectodermal

tumours

-LRB-

PNET

-RRB-

infantile

fibrosarcoma

aggressive

fibromatosis

desmoplastic

small

round-cell

tumours

and

rhabdoid

tumours

and

other

more

even

rarer

soft-tissue

tumours

such

as

nonosseous

Ewing

sarcoma

-LRB-

Fig.

-RRB-

that

should

be

kept

in

mind

when

performing

US

or

reading

CT

or

MRI

studies

of

soft-tissue

tumours

in

childhood

Fig.

girl

with

a

mass

on

the

left

buttock

a

Duplex

US

image

shows

a

highly

vascularized

well-delineated

heterogeneous

mass

that

was

initially

thought

be

a

haemangioma

b

Coronal

STIR

image

shows

a

circumscribed

solid

lesion

that

invades

the

pelvis

via

the

greater

sciatic

foramen

-LRB-

open

arrow

-RRB-

c

After

initial

resection

with

incomplete

margins

tumour

recurrence

was

seen

MR

image

years

after

initial

diagnosis

shows

progression

of

disease

extending

to

the

abdominal

wall

-LRB-

open

arrow

-RRB-

Histopathology

alveolar

RMSFig

boy

with

a

mass

in

the

right

groin

MRI

shows

a

heterogeneous

lesion

adjacent

to

the

gracilis

muscle

-LRB-

open

arrow

-RRB-

Histopathology

extraosseous

Ewing

sarcoma

Treatment

and

prognosis

Treatment

of

RMS

requires

a

multidisciplinary

approach

where

chemotherapy

surgery

and

radiotherapy

-LRB-

RT

-RRB-

each

has

its

own

specific

role

Chemotherapy

Before

the

introduction

of

chemotherapy

only

of

patients

with

RMS

survived

despite

adequate

local

therapy

This

indirectly

indicates

that

the

vast

majority

of

patients

had

at

least

minimal

disseminated

disease

at

diagnosis

whereas

with

state-of-the-art

imaging

techniques

and

bone

marrow

investigations

only

of

patients

with

RMS

present

with

overt

metastatic

disease

Besides

treating

minimal

disseminated

disease

chemotherapy

enables

local

therapy

to

be

more

conservative

In

most

patients

surgery

at

diagnosis

consists

of

biopsy

only

Chemotherapy

is

given

to

all

patients

it

reduces

tumour

size

and

extension

and

often

allows

a

delay

in

surgery

The

tumour

is

more

likely

to

be

completely

resected

and

mutilating

surgery

avoided

Most

international

protocols

use

vincristine

and

dactinomycin

as

standard

drugs

The

choice

of

alkylating

agent

differs

between

Europe

-LRB-

ifosfamide

-RRB-

and

North

America

-LRB-

cyclophosphamide

-RRB-

These

drugs

have

proved

to

be

equally

effective

but

differences

in

toxicity

exist

ifosfamide

is

more

nephrotoxic

whereas

cyclophosphamide

more

gonadotoxic

-LSB-

-RSB-

The

addition

of

other

antineoplastic

agents

to

vincristine

dactinomycin

and

alkylators

in

the

treatment

of

RMS

has

been

investigated

but

no

significant

improvement

in

outcome

has

been

found

-LSB-

-RSB-

Surgery

In

children

surgery

often

starts

during

the

diagnostic

phase

with

biopsy

for

histological

studies

although

here

interventional

radiology

plays

an

increasing

role

Excisional

biopsy

is

not

advocated

except

for

paratesticular

tumours

Most

patients

end

up

with

postsurgical

stage

IRS

group

III

Surgery

is

generally

delayed

until

after

tumour

reduction

by

chemotherapy

The

surgical

treatment

of

RMS

is

site-specific

but

the

current

paradigm

is

complete

wide

excision

of

the

primary

tumour

with

a

margin

of

uninvolved

tissue

whenever

possible

Debulking

and

mutilating

procedures

should

be

avoided

Radiotherapy

The

philosophies

underlying

the

treatment

strategies

in

North

America

and

Western

Europe

have

differed

in

the

past

North

American

protocols

involved

aggressive

surgery

and

routine

RT

except

for

those

tumours

that

were

microscopically

radically

resected

at

diagnosis

followed

by

prolonged

chemotherapy

regimens

for

up

to

years

The

SIOP-MMT

-LRB-

International

Society

for

Paediatric

Oncology

Malignant

Mesenchymal

Tumour

-RRB-

group

advocated

the

use

of

chemotherapy

and

surgery

in

order

to

achieve

complete

remission

in

as

many

patients

as

possible

in

order

to

avoid

RT

in

these

often

very

young

patients

RT

often

has

devastating

effects

in

growing

children

potentially

leading

to

significant

cosmetic

and

functional

problems

Radiation

tolerance

of

growing

bone

is

Gy

but

the

radiation

dose

from

the

treatment

of

RMS

ranges

from

to

Gy

For

certain

sites

this

policy

worked

out

well

-LRB-

e.g.

orbital

RMS

-RRB-

and

in

many

patients

RT

could

be

avoided

-LSB-

-RSB-

At

most

other

sites

relapse

rates

were

high

and

salvage

rates

after

relapse

were

low

The

treatment

protocols

in

Germany

-LRB-

Co-operative

Weichteilsarcom

Studie

CWS

-RRB-

and

Italy

-LRB-

Italian

Cooperative

Soft

Tissue

sarcoma

Group

ICG

-RRB-

were

between

that

in

North

America

and

that

of

the

SIOP-MMT

group

In

the

former

SIOP-MMT

CWS

and

ICG

joined

to

form

the

EpSSG

As

a

result

of

extensive

cooperation

between

the

European

and

the

North

American

groups

the

similarities

in

treatment

strategies

now

outnumber

the

differences

-LSB-

-RSB-

Although

RT

is

still

deemed

essential

in

many

patients

to

achieve

cure

the

possibility

of

radiation-induced

second

malignant

neoplasms

must

be

kept

in

mind

-LSB-

-RSB-

European

approach

Today

more

than

of

nonmetastatic

RMS

are

cured

but

survivors

may

suffer

from

sequelae

-LSB-

-RSB-

Therefore

the

SIOP-MMT

group

has

tried

in

their

and

studies

to

avoid

mutilating

surgery

and

RT

-LSB-

-RSB-

Only

children

years

of

age

with

parameningeal

RMS

at

high

risk

of

meningeal

extension

and

children

not

achieving

complete

remission

after

chemotherapy

and

surgery

were

irradiated

after

intensive

chemotherapy

Of

all

survivors

were

treated

without

significant

local

therapy

-LSB-

-RSB-

Locoregional

relapse

occurred

in

This

has

lead

to

an

event-free

survival

-LRB-

EFS

-RRB-

of

and

an

overall

survival

-LRB-

OS

-RRB-

of

-LSB-

-RSB-

Alveolar

histology

was

associated

with

a

significantly

higher

risk

of

relapse

and

a

much

higher

risk

of

metastases

North

American

approach

In

the

studies

performed

by

the

IRSG

the

need

for

RT

is

based

on

surgical

radicality

localization

and

size

of

the

primary

tumour

Only

completely

resected

tumours

-LRB-

IRS

group

I

-RRB-

with

a

favourable

location

-LRB-

stage

I

Table

-RRB-

and

small

tumours

-LRB-

cm

-RRB-

at

unfavourable

locations

-LRB-

stage

II

-RRB-

did

not

receive

RT

in

the

IRS-IV

study

-LSB-

-RSB-

Grossly

resected

tumours

with

microscopic

residual

disease

-LRB-

IRS

group

II

-RRB-

and

incompletely

resected

tumours

or

tumours

with

gross

residual

disease

after

biopsy

-LRB-

IRS

group

III

-RRB-

were

irradiated

-LSB-

-RSB-

With

this

approach

in

the

IRS-IV

study

an

EFS

of

and

an

OS

of

were

obtained

Between

the

IRSG

and

SIOP-MMT

group

a

significant

difference

in

OS

in

alveolar

RMS

was

seen

-LRB-

vs.

-RRB-

-LSB-

-RSB-

The

salvage

rate

after

relapse

of

an

alveolar

RMS

was

low

and

therefore

in

the

current

European

trial

RT

is

mandatory

for

all

patients

with

alveolar

histology

Table

Oncology

Group

and

Children

's

Cancer

Group

for

the

Study

of

Rhabdomyosarcoma

classification

-LSB-

-RSB-

StageSitePrimary

tumouraSizebRegional

nodescDistant

or

or

or

and

neck

-LRB-

excluding

parameningeal

-RRB-

Genitourinary

nonbladder

nonprostateIIBladder

and

or

or

parameningealOther

-LRB-

including

trunk

retroperitoneum

etc

-RRB-

IIIBladder

and

or

or

or

-LRB-

including

trunk

retroperitoneum

etc

-RRB-

IVAll

or

or

or

tumour

limited

to

original

muscle

or

organ

tumour

has

extension

or

fixation

to

the

surrounding

tissue.ba

tumour

equal

to

or

less

then

cm

in

greatest

dimension

b

tumour

larger

than

cm

in

greatest

no

clinical

involvement

of

regional

nodes

clinical

involvement

of

regional

nodes

NX

status

of

regional

nodes

no

distant

metastasis

distant

metastasis

As

described

above

European

and

American

approaches

although

historically

different

have

converged

based

on

the

results

of

successive

international

trials

and

extensive

cooperation

between

the

European

and

North

American

groups

-LSB-

-RSB-

As

approaches

now

are

very

similar

in

this

review

the

current

EpSSG

approach

for

the

different

clinical

groups

is

discussed

Current

EpSSG

approach

IRS

group

I

In

the

IRS-I

study

a

randomized

trial

in

clinical

IRS

group

I

patients

no

difference

was

seen

in

survival

between

patients

treated

with

chemotherapy

and

those

treated

with

chemotherapy

and

RT

-LSB-

-RSB-

A

subsequent

retrospective

study

based

on

the

subsequent

IRS-I

to

IRS-III

trials

confirmed

that

for

embryonal

RMS

although

there

was

a

small

difference

in

failure-free

survival

-LRB-

FFS

-RRB-

with

and

without

RT

OS

was

not

significantly

different

-LSB-

-RSB-

On

the

other

hand

for

alveolar

RMS

and

undifferentiated

RMS

FFS

was

vs.

and

OS

vs.

for

patients

treated

with

and

without

RT

respectively

-LSB-

-RSB-

Therefore

the

current

EpSSG

study

recommends

RT

in

non-embryonal

RMS

only

IRS

group

II

Evaluation

of

the

role

of

RT

in

IRS

group

II

patients

in

subsequent

Cooperative

Soft

Tissue

Sarcoma

studies

-LRB-

CWS

and

-RRB-

showed

that

for

embryonal

RMS

EFS

was

significantly

different

for

patients

treated

with

and

without

RT

-LSB-

-RSB-

However

OS

at

years

was

not

significantly

different

-LRB-

vs.

-RRB-

For

patients

with

tumours

of

unfavourable

histology

-LRB-

independent

of

site

and

size

-RRB-

EFS

and

OS

were

significantly

better

when

RT

was

part

of

the

treatment

-LSB-

-RSB-

Therefore

in

IRS

group

II

patients

RT

is

recommended

It

is

compulsory

in

patients

with

high-risk

features

but

may

be

omitted

in

patients

with

favourable

histology

in

whom

RT

may

be

considered

too

toxic

when

considering

patient

age

and

site

of

the

tumour

IRS

group

III

In

patients

with

IRS

group

III

tumours

RT

is

the

only

available

therapy

in

patients

who

can

not

receive

a

secondary

complete

resection

Patients

who

do

receive

a

delayed

complete

resection

benefit

from

additional

RT.

In

the

CWS

trials

EFS

was

and

for

those

treated

with

and

without

additional

RT

respectively

-LSB-

-RSB-

OS

however

was

not

significantly

different

between

the

two

groups

and

respectively

RT

is

therefore

usually

indicated

except

in

patients

with

a

favourable

site

and

histology

Prognosis

As

malignant

tumours

in

childhood

are

rare

diseases

most

children

with

cancer

have

been

included

in

international

treatment

protocols

This

way

survival

for

localized

disease

-LRB-

of

patients

-RRB-

has

improved

from

in

the

early

to

in

the

most

recent

international

trials

-LSB-

-RSB-

Although

results

for

localized

RMS

have

improved

dramatically

in

the

past

decades

patients

with

disseminated

disease

still

have

a

dismal

prognosis

with

a

OS

of

-LSB-

-RSB-

A

way

to

reduce

long-term

sequelae

of

RT

may

be

by

using

brachytherapy

especially

in

girls

with

genital

tract

RMS

and

patients

with

bladder-prostate

extremity

and

head

and

neck

RMS

-LSB-

-RSB-

Other

options

are

the

use

of

modulated

RT

-LRB-

IMRT

-RRB-

and

proton

therapy

-LSB-

-RSB-

The

postoperative

patient

Image

interpretation

and

management

of

the

patient

after

surgery

and

often

RT

are

challenges

-LRB-

Fig.

-RRB-

Most

important

is

proper

knowledge

of

the

surgical

procedure

and/or

the

radiation

field

The

following

postoperative

changes

can

be

encountered

in

children

treated

for

RMS

HaematomaOedemaSoft-tissue

infection/abscessCalcificationForeign

bodiesMuscle

flaps/fat

padsDistorted

anatomyRadiation

effect

Figure

shows

a

possible

decision

tree

to

manage

postoperative

findings

on

follow-up

imaging

Fig.

boy

with

a

history

of

treated

bladder

RMS

At

surgical

resection

the

urethra

was

damaged

leading

to

a

persistent

urinoma

in

after

RT

nonvital

tissue

MRI

image

after

treatment

shows

a

mass

-LRB-

asterisk

-RRB-

between

the

urethra

-LRB-

open

arrow

-RRB-

and

the

rectum

-LRB-

solid

arrow

-RRB-

This

mass

is

a

vascularized

gracilis

muscle

flap

used

to

repair

the

defect

Without

proper

knowledge

of

the

surgical

history

of

the

patient

this

might

have

been

interpreted

as

tumour

recurrence

Histopathology

embryonal

RMSFig

chart

for

posttreatment

lesions

found

on

MRI

SI

signal

intensity

CE

contrast-enhanced

-LSB-

-RSB-

Conclusion

In

this

review

we

have

discussed

the

findings

of

RMS

outside

the

craniofacial

region

The

treatment

of

RMS

requires

a

multidisciplinary

approach

in

which

paediatric

oncologists

radiologists

paediatric

surgeons

pathologists

and

radiation

oncologists

all

play

a

vital

role

Although

they

are

the

most

common

soft-tissue

tumour

of

childhood

these

still

rare

tumours

should

be

evaluated

and

treated

in

specialized

centres

B O O O O B B O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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