Are Oncologists More Open Minded Than Cardiologists?

Richard S. Leff, MD, FACP
Nov 13, 2012 4:20 PM

How open minded are we as physicians and scientists?  With the rapid change and improvement in cancer knowledge and treatment do oncologists see the world differently than other specialists?

Last week at the American Heart Association annual meeting, a study of chelation therapy after acute MI showed a statistically significant decrease in cardiac events (HR 0.82, P=0.035) in a well-designed randomized trial including over 1700 patients followed for an average of 4 years.  As with many studies, this one left many questions unanswered.  The reactions to the study, however, provided an interesting commentary about how our biases affect interpretation of data.  Although the study was appropriately designed and conducted, based on their reactions to the results the investigators apparently had a preexisting bias against the investigational arm.  The positive findings were reportedly a surprise to investigators and an embarrassment to cardiologists and the AHA.  When chelation therapy was shown to be superior, the reaction of cardiologists was to dismiss the results based on lack of a good explanation of mechanism of action and failure to fit into their set of long-held beliefs.   No one advocated a change in standard post-MI therapy and there was apparently no serious discussion about a follow up study to verify the results.  So much for believing in the value of randomized studies with valid statistical endpoints!   

How would oncologists react to a positive study for a treatment they didn’t believe in?  My experience suggests that we wouldn’t differ much from the cardiologists.  Medical marijuana may serve as good evidence.   A few weeks ago I had the pleasure of hosting a webinar about medical uses of marijuana with Dr. Donald Abrams.  Dr. Abrams is the Chief of Hematology-Oncology at San Francisco General Hospital and Director of Clinical Programs at the Osher Center for Integrative Medicine at UCSF.  His scientific and medical background is impressive and he has led and participated in numerous landmark studies in cancer and AIDS.  Along with these studies he has designed and conducted several studies of use of marijuana in patients with cancer or AIDS.  His studies (as well as those of other investigators) and the accompanying preclinical science suggest that active agents in marijuana may be very helpful in reducing pain (including neuropathic pain), improving appetite and decreasing distress.  These results are drawn from carefully controlled small trials, not anecdotal reports.   The studies demonstrate a significantly better outcome with marijuana than we usually expect with pharmaceutical cannabinoid preparations. The preclinical evidence suggests that our pharmaceutical cannabinoids may not achieve most of these results due to selection of individual agents which do not have the overall effect of the combinations found in nature.  I have to admit that I was surprised by the data as well as by the scientific rigor of the studies. 

Why are none of these data presented at ASCO meetings?  The apparent answer is both surprising and distressing.  ASCO leadership has reportedly considered and rejected the idea of an educational session about medicinal marijuana.  Maybe it is politically too sensitive or not considered serious enough for our annual meeting.  Perhaps there is not enough perceived interest.  Based on a discussion on our Oncology online community,, many oncologists have dismissed marijuana as unnecessary and perhaps even harmful.  Unfortunately, I would guess that most of them are unaware of the available data which suggest otherwise.  Certainly the data are not definitive proof that marijuana should be used as an adjuvant for pain, anorexia, nausea or anxiety, but ASCO is committed to encouraging exchange of information among cancer experts that might help accelerate advances in cancer treatment.   We will never know for sure how helpful marijuana might be unless we ask the right questions and create and support the right studies.  Medical use of marijuana is currently legal in 17 states.  Isn’t it time that ASCO provided some scientific education to its members about this agent or must we depend on our patients to teach us?