Archive for the ‘Scientific American magazine’ Category

Prostate Cancer Controversies

Friday, September 7th, 2012

A prostate cancer awareness symbol

Prostate cancer is the most common cause of cancer death in older men. A few years ago most of us males over the age of forty (it seldom occurs before that) were periodically screened for the disease using the PSA test (a blood test for a prostate-specific antigen) and had digital rectal exams to check the size and consistency of our prostates whenever we had our yearly appointment for a physical and also had comprehensive lab work done.

Then things changed: the annual medical exam was discarded by most physicians in favor of a targeted examination, which in my case, with my history of high blood pressure, includes a nurse taking my BP and my doc listening to my heart and lungs. Not much else, unless I have a specific complaint. I'm 71 and haven't had a digital exam for five years. I had a PSA done when blood was drawn for other reasons and it was 0.7, well under the level that would have raised any concern about my prostate.

In October, 2011, the Harvard Health Blog provided two points of view on pending new recommendations for prostate-specific antigen (PSA) testing from the U.S. Preventive Services Task Force. A panel of experts after a thorough review of the literature on prostate cancer had concluded, that for men over 50, screening using the PSA test offered a low benefit to risk ratio. A huge controversy broke out with the American Urological Association arguing against the proposed new concept. Other physicians noted that an elevated PSA doesn't always mean cancer and, much more importantly, doesn't  distinguish which cancers of the gland are likely to be fast-growing and life threatening.

Oncologist, Dr. Marc Garnick, editor of Harvard's "Annual Report on Prostate Diseases," noted that the new testing recommendation was not a blanket statement fitting all men: those at higher risk (African-Americans and men with family history of cancer of the prostate) may still be suitable candidates for annual PSA testing. He later published an article in Scientific American mentioning that the use of regular PSA testing had led to over a million men having treatment for prostate cancer since 1985 and many thousands of men having complications of prostate surgery or radiation therapy (impotence, incontinence, rectal bleeding).

Dr. Garnick basically agreed with the task force's conclusions; felt the evidence supporting regular PSA testing was flimsy, but thought that the procedure gave important information after a cancer of the gland has been diagnosed.

Garnick was interviewed by a senior editor of the magazine and the resultant February 8, 2012, piece supplies audio comments from Dr. Garnick which detail some of the issues. One such concerns a man who has had his malignancy removed by a total (radical) prostatectomy. His PSA should plummet down to undetectable levels and, if it doesn't, either not all the cancer was excised or there has been spread beyond the local area (metastases).

I was reading my email a few days ago and noted one from my friend Rick with a link leading to an article from the Fred Hutchinson Cancer Research Center in Seattle titled "Prostate Cancer: 6 things men should know." There were six myths rebutted and I especially noted four conclusions: eating tomato-based foods and products doesn't prevent the malignancy; high testosterone levels don't correlate with risk of this tumor; omega-3s don't lower the risk (actually very high blood levels in one study were associated with higher risk); dietary supplements (selenium and vitamin E) don't prevent the disease.

At age 50 and above, this was on my schedule; at age 71 it's not

Another online publication from the Hutchinson Center gives background information on prostatic cancer. They note the frequency of the disease increases in men over 55, that obese men have a higher risk of developing an aggressive form of the disease, as do smokers. Those who drink red wine (four 4-ounce glasses a week) were noted to have a 60% lower incidence. Older men may receive unnecessary surgery; in this group the malignancy, often small and slow-growing, may not be life-shortening.

The need for screening in the general population of men is an ongoing medical controversy. We'll likely hear much more about PSA testing, but many would concede that a new type of evaluation needs to be developed.

I agree and for now I don't plan to have any more PSAs drawn.