[ RadSafe ] What does it mean to say that something causes 16%of Ca?

[Chris Alston]

My apologies, folks, I unaccountably sent the message below originally to
the AMRSO list, not to Radsafe.  I don't think that any confidentiality was
violated, but it is the principle of the thing, no?

Yours in chagrin
cja

---------- Forwarded message ----------
From: Chris Alston <achris1999 at gmail.com>
Date: Fri, May 11, 2012 at 8:09 PM
Subject: Fwd: [ RadSafe ] What does it mean to say that something causes
16%of Ca?


Prof. Doss

Thank you for this very succinct, and lucid, statement of (maybe) the
crucial aspect of the problem of prevention of carcinogenesis.  I would
only add that another crucial part of dealing with Cancer Land (as a
beloved friend of mine, who has had to wrestle in that arena, calls it) is
that of Early Detection.  The fact of the matter is that we already have
excellent (by which I mean highly probable of cure, and without hugely
challenging side effects or adverse reactions) tools to fight most Ca in
(ideally) Stage I, or (not as good) Stage II.

The problem is that we cannot tell that it is there, most of the time,
until it is too late for an "easy" fix.  E.g., ovarian Ca is a notorious,
and, rightly, much feared killer, yet that is largely because, by the time
it is found, it is too late for curative tx.  If we had a test for it,
comparable to the PSA test, by which we could find it in situ, the surgeon
could remove the ovaries, and that would be the end of it.  The same goes
for pancreatic Ca, which seems to be much in the recent news.

It is even true, I would bet, of later Stage tumors, say, breast Ca.  The
problem there, in part, is that we cannot tell, in a timely way, whether or
not a primary tumor has been treated successfully.  So, a woman is
diagnosed and treated, and gets followup, for five years, or ten years, or
fifteen years, and then the Ca "comes back".  Well, it did not literally
"come back", of course, it was always there, we simply did not have the
means to detect it.  I would venture that, if one could tell, within a
couple of years after attempting curative tx of breast Ca, that the tx had
failed, there would be options for further tx that would be available,
which would not be workable ten years post-tx.

I await the slings and arrows happily,

Cheers
cja

P.S.  Please note that the vaccine for HPV is likely even more effective as
an anti-carcinogenic tool than it is advertised, since HPV may also
engender head and neck tumors and those are much more lethal, and the tx is
much more difficult, both for physician and for patient, than cervical Ca.
 Heck, the latter can be found at a pre-malignant phase, and excised,
without great discomfort to the pt or expense.



---------- Forwarded message ----------
From: Mohan Doss <mohan.doss at fccc.edu>
Date: Fri, May 11, 2012 at 4:20 PM
Subject: Re: [ RadSafe ] What does it mean to say that something causes
16%of cancers?
To: "The International Radiation Protection (Health Physics) Mailing List" <
radsafe at agni.phys.iit.edu>


I agree with you that cancers are symptoms of an underlying condition.

A few points to note:
1.  About 45% of the population is likely to be diagnosed with cancer in
their lifetime (ACS estimate, e.g.).  You may think the remaining 55% of
the population do not have cancer.  However, when autopsies are performed,
you are likely to find cancer cells in almost all of them (if they are well
into their old age).
2. When the immune system is suppressed, e.g. in AIDS patients or organ
transplant patients, the cancer risk goes up by a factor of about 2.4.
 Thus, the 55% of population that you thought do not have cancer will have
cancer, if we suppress their immune system.  We can probably extrapolate
this backwards and say that if you improved the immune system, you would
decrease the cancer, and maybe eliminate the cancer altogether.  One method
of boosting the immune system is regular moderate vigorous exercise.  This
is known to reduce cancer incidence and mortality for many types of
cancers.  Another method of boosting the immune system is through low dose
radiation.  Low dose radiation is known to reduce cancers in controlled
studies in animal models.  For humans, though reduction in cancers has been
observed from low dose radiation in many retrospective studies, the
potential confounding factors make it difficult to convince all scientists
(or the general public) who are scared of the low dose radiation.  We need
controlled clinical trials to determine conclusively the effectiveness of
low dose radiation in preventing cancers.

Thus the underlying condition that causes (most) clinical cancers is
deficiency in the immune system (in my opinion, based on the above points).
 So long as we don't recognize this factor, and deal with it, we are not
likely to succeed in conquering cancer.  Thus our current radiation safety
system based on the LNT model (which completely ignores the effect of low
dose radiation on the immune system) is a major failure of our current
scientific society.  If what I have said here is shown to be true in the
future, people are going to refer to our present days as the Dark Ages with
regard to radiation, and wonder how we did not recognize the importance of
the immune system in preventing cancer for so long (~40 years).

With best regards,

Mohan Doss, Ph.D., MCCPM
Medical Physicist, Diagnostic Imaging,
Associate Professor,
Fox Chase Cancer Center, R427