Archive for the ‘prostate cancer’ Category

Treating Prostate Cancer: only $93,000 for 4 Months

Saturday, May 8th, 2010

 

NBC Nightly News (4/29, story 3, 2:00, Williams) reported that “the FDA has approved” Provenge (sipuleucel-T), “a vaccine for prostate cancer. It doesn’t prevent the disease, so vaccine is a bit of a misnomer, ..it could be a game-changer.”  The the media hype goes on: “It could help as many as 100,000 men with advanced prostate cancer,” the CBS Evening News (4/29, story 7, 2:00, Katie Couric) reported.  It offers “a new way to attack the disease which could be deployed against other kinds of cancer,” ABC World News (4/29, story 7, 1:55, Diane Sawyer) reported. But this is typical media hype, unsupported pure speculation.

 

The AP  reports that “three years ago…the FDA delayed a decision on the treatment, “despite an expert panel’s recommendation for approval.” According to the Los Angeles Times  “agency officials were concerned that, even though the vaccine extended lifespan in men with metastatic cancer who did not respond to hormone-deprivation therapy…it did not slow tumor growth.” The FDA also said that too few men given Provenge had been studied and asked Dendreon to perform a larger trial in more than 500 men.

 

Those results were presented last year, see TheWashington Post. During the trial, which involved “512 patients with advanced prostate cancer, Provenge increased overall survival by about four months, boosting median survival from 21.7 months to 25.8 months.”

 

The New York Times (4/30, A13, Pollack) reports that “a full treatment (with Provenge) will cost $93,000. Dendreon officials defended that price, saying it was in line with those of other cancer drugs in terms of cost per extra month of life provided by the drug.”

 

Bloomberg News said that the treatment “will initially be available at about 50 sites used for clinical trials, and more widely distributed after four plants are cleared for use by mid-2011, Seattle-based Dendreon said in a statement.”

 

But why did the FDA approve the drug without further testing?  It’s increasingly clear that  public pressure for life-extending new drugs for cancer is irresistible.  Would you like to take a chance on 4 miserable months for $23,000 a month, on the basis of this single study? Tough question. Is it time to load up on Dendreon stock?










PSA Screening for Prostate Cancer: Does it Save Lives?

Saturday, April 4th, 2009

The prostate specific antigen (PSA) test to detect early prostate cancer has been publicized  with unbounded enthusiasm ever since it was introduced in the late 1970’s. In the last several years, however, the use of the test has become increasingly controversial. With a death rate of 25 per 100,000 men, prostate cancer is still the second leading cause of cancer deaths among men, but well behind lung at 70/100,000. Yet many forms of prostate cancer remain dormant for decades.  For example, at autopsy, prostate cancer is found incidentally (in those dying of other causes) in 30% of men of 50, rising to 55% over 80 and almost 100% of men over 90. Moreover, the 5-year survival rate, the percentage of men who do not die from prostate cancer within 5 years after the cancer is found is 100%, and the relative 10 and 15 year survivals are 91% and 76% respectively.  Since current treatments, outside of “watchful waiting” and hormone therapy, consist of radical surgery and radiation, both accompanied by high rates of complications, the incidental discovery of early prostate cancer cannot be taken lightly.

Two recent landmark studies have just been published in the New England Journal of Medicine, one involving more than 76,000 men.  This U.S. Government-funded study found that the PSA screening test did not reduce the death toll from prostate cancer in the first decade. The second study, a European trial involving more than 162,000 men, did report fewer deaths among those tested, but the reduction was relatively modest, and some experts said the study design made estimates of reduction difficult to interpret.  The European study did confirm what has been known for years, that large numbers of those screened suffered needless and often harmful treatment.  Among men undergoing radical prostate surgery, 55%-76% suffer severe erection problems and impotence, and up to 50% experience urinary incontinence for over a year or longer following operation.  Reliable figures on persistence of impotence are difficult to find, but a significant number of these men had permanent loss of sexual function.  Different types of radiation treatment also resulted in erectile dysfunction and urinary incontinence, but the complication rates tend to be lower.

Because of the uncertainty resulting from these and previous studies, many major medical groups have stopped recommending routine PSA screening.  The U.S. Preventive Services Task Force which sets federal policy on preventive health care, last year recommended doctors stop testing elderly men, and concluded that it was unclear if screening was worthwhile for younger men. In the European study of men between 55 and 69, the figures at best mean about 10,000 men would have to be screened for 10 years to prevent seven deaths from prostate cancer.  Expressed another way, 1410 men would need to be screened and 48 would have to be treated to prevent one death.

Because of increasing evidence of ineffectiveness and unforeseen consequences of PSA screening, many patients are now given helpful information about the test and can elect to forego it.  This is not the option, however, if a man gets a freebie at the local shopping mall.  Sadly, the enthusiasm about finding prostate cancer “early” continues to trump evidence that doing so may indeed cause more harm than good. PSA screening will probably be with us for many years into the future.