Evening star., 1936-05-12
BY THOMAS r. HENRY.

KANSAS CITY, Mo. May IA
possible major advance in the radia-
ton treatment of inoperable and
hitherto usually hopeless malignant
tumors was presented in an exhibit
before the American Medical Associa-
ton here today by Drs. E. A. Merritt,
r. Rhett Rathbone and Edgar M.
McPeak of Garfield Hospital in Wash
ington.
Cancers in any part of the body
now can be reached with X-ray
dosages five times as great as has
been feasible before. Relatively
enormous concentrations can be
directed against malignant growths in
the stomach. colon, liver, kidneys and
pancreas. While the Washington
doctors do not claim cures of these
inoperable cancers, they have been
able to improve greatly the condition
Of the victims.
The technique, developed under the
direction Of DR.. Merritt, is a radical
extension Of the system first intro
duced about 10 years ago by the
French X-ray specialist Coutard, who
used heavier filters for the X-rays to
pass through before striking the body.
The Washington doctors have devised
a filter of tin, replacing copper. which
allows the passage Of 80 per cent
more of the rays needed.
Effect of Shorter Rays.
The second contribution from the
Washington clinic is in the form Of
evidence that, contrary to all the
assertions of physicists in the past,
there is a differential effect of long
and short X-rays on human tissue.
The 220.000-volt X-ray spectrum runs
from relatively long rays overlapping
the spectrum Of ultraviolet light. to
short gamma rays" which overlap
the gamma ray spectrum of radium
by about 20 per cent. The shorter
the rays. the deeper they will pene-
trate into tissue and the thicker the
copper or tin filter they will pass
through.
The destructive effect of the longer
X-rays, DR.. Merritt asserts. is great
est against the connective tissues of
the body, while the part of the spec
trum which overlaps the radium
spectrum is chiefly destructive Of skin
and other epithelial tissue. It so
happens, according to the Washing
ton doctors, that the resistance of
tumor tissues is much closer to that
Of the skin than to that Of connec-
tive tissue.
Their new tin filter lets through
only the band in which the X-ray
and radium spectrums overlap.
Former Difficulty.
One of the great drawbacks to
treatment of internal cancers with
X-rays in the past has been the fact
that, when enough of the whole X-ray
spectrum was directed against them,
the beam sufficiently potent to reach
and destroy the malignant cells
caused such extreme destruction Of
the connective tissues through which
it must pass that the cure was more
than the disease. The patient usual
" died anyway. The long rays which
destroy the flesh and blood cells were
a complete waste. since very few OF
them ever actually reached the
cancer.
The short rays cause some destruc-
tion of the connective tissue through
which they pass, but this is much
reduced All of them reach the
malignant growth for which they are
intended. The effect on the skin is
less than when the entire spectrum
is used. One criterion OF dosage
suficient to cause any cancer cell de-
struction is an extreme blistering
of the epidermis, but this tends to
heal in the course Of treatment ex-
tending for a month or two, and
leaves no permanent i'll effects.
The third step in the new cancer
therapy is the long period over which
it Is given. It has usually been tne
practice In X-ray clinics to give the
entire treatment in four to six dosages.
The patient could not stand any more.
About 1,500 roentgen units was about
the limit. The new treatment devised
by the Washington doctors Is to give
only about 200 units of the short rays
but to repeat the dosage six days
week for a month or more. Thus they
can direct against the cancer maxi
mum of more than 5000 units. The
rays are directed against different sides
of the body-a cancer OF the stomach
being treated alternately from three
portals of entry.
AS explained by DR.. McPeak. the
cancer cell is in its weakest state in
its infancy, Just after one adult cell has
divided forming two baby cells" In
the course Of 30 dayS. they ~. every