# Presentation: 505515

## Proposed WHO Classification of Lymphoid neoplasm

_**B cell neoplasm**_

**Precursor B cell neoplasm**

**Precursor B-lymphoblastic leukemia/lymphoma**
**(precursor B-ALL)**

**Precursor T-cell and NK-cell neoplasm**

**Precursor T-lymphoblastic lymphoma/leukemia **
**(precursor T-ALL)**

_**T cell neoplasm**_

## Mature (peripheral) B cell neoplasm

**B-cell chronic lymphocytic leukemia/SLL**

**Lymphoplasmacytic lymphoma**

**Splenic marginal zone B-cell lymphoma**

**Hairy cell leukemia**

**Plasma cell myeloma/plasmacytoma**

**Extra-nodal marginal zone B cell lymphoma of MALT type**

**Nodal marginal zone B cell lymphoma**

**Follicular lymphoma**

**Mantle cell lymphoma**

## Diffuse large B cell lymphoma

- Mediastinal B cell lymphoma

- Primary effusion lymphoma

**Burkitt lymphoma/Burkitt cell leukemia**

**Mature (peripheral) B cell neoplasm (cont’d)**** **

## Mature (peripheral) T cell neoplasm

- T-cell prolymphocytic leukemia

- T-cell granular lymphocytic leukemia

**Aggressive NK-cell leukemia**

- Adult T-cell leukemia/lymphoma (HTLV1)

- Extranodal NK/T cell lymphoma, nasal type

- Enteropathy type T cell lymphoma

**Hepatosplenic gamma delta T cell lymphoma**

**Subcutaneous panniculitis-like T cell lymphoma**

- Mycosis fungoides/Sezary syndrome

## Mature (peripheral) T cell neoplasm (cont’d)

- Anaplastic large cell lymphoma, T/null cell,  primary cutaneous

- Peripheral T cell lymphoma, NOS

- Angioimmunoblastic T cell lymphoma

**Anaplastic large cell lymphoma, T/null cell,   primary systemic**

## Hodgkin's lymphoma (Hodgkin's disease)

**Classical Hodgkin's lymphoma**

- Lymphocyte-rich classical Hodgkin's lymphoma

- Lymphocyte depletion Hodgkin's lymphoma

**Mixed cellularity Hodgkin's lymphoma**

**Nodular sclerosis Hodgkin's lymphoma (grades 1 and 2)**

**Nodular lymphocyte predominant Hodgkin's lymphoma**

## Pediatric Follicular Lymphoma

**Rare lymphoma subtype in children (1-2%)**
**60% present in head and neck**
**Tonsils, nasopharynx**
**Other sites: lymph nodes, GI tract, testis**
_**Many differences with FL in adults**_
**Usually Grade II-III**
**Bcl-2 usually negative (both protein & bcl-2R)**
**Male: Female****	****ratio****	****	****3:1 ****	**
**85% present with Stage I or II disease**
**75% CR with low relapse rate**

## Children

**BL**

**Children**

**BL**

**LBCL**

**Adults**

## Burkitt-like lymphoma should exist?

**Burkitt-like lymphoma should be included in:**

- Diffuse large B cell lymphoma

- or

- Morphologic variant of Burkitt lymphoma

## Burkitt and Burkitt-like Lymphomas

**May show follicular colonization**

**Cytologically tumor cells resemble the small blasts of the dark zone of the GC**

**High rate of somatic mutations of Ig VH**

**BCL-6+, CD 10+**

_**Evidence favors a germinal center derivation**_

## Burkitt-like Lymphomas

**Similar to BL, but with greater variation in nuclear morphology**
**MIB-1 100%, CD10 +, bcl-2  -**
**Cytogenetics or molecular genetics desirable for diagnosis - should have a c-myc translocation**
**This morphologic variant more common in immunodeficiency states**

## In the WHO classification

**The term “Burkitt-like lymphoma” is retained**

**Burkitt-like lymphoma will be considered  a variant**
**of Burkitt lymphoma**

**Major criteria:**

## BURKITT LYMPHOMA

**Morphologic Variants**

**Subtypes, clinical genetic**

- Endemic

- Sporadic

- Immunodeficiency-associated

- Classical Burkitt lymphoma

## Anaplastic Large Cell Lymphoma

**Paradigm for process used to define disease entities (REAL)**
**First recognized based on **
**Morphology - sinusoidal growth**
**Antigenic phenotype  - CD30+**
**Studies of molecular pathogenesis led to new diagnostic tools**
**RT-PCR and ALK-1 monoclonal antibody**
**New diagnostic tools define the borderlands of the disease**

## Anaplastic Large Cell LymphomaClinical Features

**Presents most commonly in lymph nodes**
**Cutaneous involvement variable**
**Most common in children, young adults**
**Frequent presence of systemic symptoms**
**“****B” symptoms or high IPI less often predict poor outcome (in contrast to most other NHL)**
**Aggressive natural history but good response to chemotherapy**

## Sex Ratio= 1.34

**Age**

**DISTRIBUTION OF ANAPLASTIC LARGE CELL LYMPHOMA BY AGE **
**(267 cases)**

**Number of cases**

**Sex Ratio= 1.34**

## Survival of 154 patients with ALCL 

**Survival**

**Months**

- ALK+ (n=132)

- ALK - (n=22)

- 0

**75**

**120**

**180**

**240**

**25**

**50**

**100**

**60**

**p<0.001**

## Clinical Significance of ALK + in Anaplastic Large Cell Lymphoma

**ALK+ cases are seen in younger age groups**
**Children and young adults; M>>F**
**ALK+ cases have better prognostic than ALK-, irrespective of other clinical features;  i.e. age, stage or IPI**
**Conclusion:**** **
**ALK+ ALCL is probably a distinct disease entity, separate from ALK- ALCL**