[ RadSafe ] CT vs. X-Ray for reduction of Cancer Death

[garyi at trinityphysics.com]

Hi Sandy,

I will be devil's advocate.

RE CT as a cost effective Ca preventative, here is a back of the envelope, per person 
estimate.  Assume at least 100 patients per week (200 is doable), 50 wks per yr, 4 yr scanner 
lifetime (a conservative estimate).  That's 20,000 scans for every scanner.  Assume the 
scanner costs $1e6.  That would be $50 per person for each scan.  Throw in another $50 per 
person to make the venture profitable.  Voila!  For $100/yr, reduce your risk of lung Ca 
mortality by 20% and your overall mortality risk by 7%.  If (its a big if, I know) it turns out that 
annual CT scans do significantly reduce cancer mortality, and if I'm approximately right about 
the economics, then new CT clinics would spring up like mushrooms to meet demand.  
Haha, maybe the study authors are quietly buying up CT stocks now.  :)

But it does seem economical, and I haven't even considered the savings due to cancer 
treatments that are no longer needed, or the savings due to prolonged productivity of those 
who dodge the Ca bullet.  There's also the advantage of dying from something that is often 
quick, like stroke or heart attack, instead of lingering painfully on your way to death.

One test that should be applied to the existing NLST cohort is Ca incidence instead of just 
mortality: did the CT screened group have significantly lower incidence of lung cancer than 
the chest x-ray group?  If so, it would certainly support the idea of CT scans as a Ca 
prophylactic.

It seems almost that people are afraid to ask some questions.

> The notion that everyone would benefit from a higher dose of r
>  adiation in my opinion is not acceptable, nor is there evidence that there is any positive benefit. The risks are
>  well-known and to ignore the known facts cannot be ignored.

I think you mean "not proven" instead of "not acceptable".  Yes, if the data show that the 20% 
is due only to early detection, then I agree with you.  I merely think we should find out what 
the data show.  Simply assuming that hormesis can not play a role in the study results would 
be a lamentable case of jumping to conclusions.  Historically, lung cancer has been difficult 
to treat, and I would be surprised if the huge difference in mortality can be wholly due to early 
detection.

-Gary Isenhower


On 7 Nov 2010 at 12:22, Perle, Sandy wrote:

A reduction of any illness/disease through the use of technology does not imply that every 
individual in the entire population should undergo that application/procedure with the stated 
goal of reducing the long-term probability of said individual to detect and minimize the effects 
of that illness/disease from occurring. There are many preventative exams that can be 
conducted today for age specific, genetically prone individuals, to be tested, at an economical 
cost. Just considering the cost of CT scans and the economic effect if everyone was to 
receive this exam, would be not cost effective. Another point is the assumption that somehow 
this dose may be a positive outcome is simply not acceptable. Personally I still am of the 
opinion that exams involving either radiological or nuclear medicine should only be utilized 
where there is a distinct requirement for the exam to diagnose an illness or confirm the 
diagnosis. The notion that everyone would benefit from a higher dose of r
 adiation in my opinion is not acceptable, nor is there evidence that there is any positive 
benefit. The risks are well-known and to ignore the known facts cannot be ignored.

Regards,

Sandy
____________________
Sander C. Perle
President
Mirion Technologies
Dosimetry Services Division
2652 McGaw Avenue
Irvine, CA 92614