Prostate Cancer, Provenge, Therapeutic Vaccine, Dendreon Corporation

I read yesterday that Dendreon Corporation had announced initial findings of a second study that was completed evaluating the effectiveness of a vaccine for treatment of advanced prostate cancer. This is big news as there have not been very effective treatments for cancer that has spread outside of the prostate capsule. As I have mentioned before prostate cancer is the second leading cause of cancer death in men with 186,000 new cases per year in the United States and 28,000 deaths. There is no effective chemotherapy. Radiation treatment is only helpful for localized spread and hormone treatment for metastatic disease is not that good, so anything that might be helpful is good news.

Dendreon Corporation is trying to get FDA approval for Provenge cancer vaccine. It would be the first cancer vaccine on the market. It does not prevent disease but is a "therapeutic" vaccine that trains the immune system to fight tumors. Provenge is made from the patient's own immune blood cells that are mixed with a protein found on most prostate cancer cells and is given back to the patient in 3 separate infusions given 2 weeks apart. These "trained" immune cells then fight the cancer cells.

The company did not release the details of the Provenge study nor side effects which will be presented at an American Urological Association conference later this year. The study involved 512 men with cancer that had spread outside the prostate and was no longer responding to hormone treatment. It was found that the drug does not slow the progression of the disease but does increase survival time by 4 1/2 months or longer. While this as an average doesn't seem that much, in practical terms three year survival rates were 34% vs. 11% without treatment. For prostate cancer treatment those are big numbers. I am interested to see the full report when it becomes available.

Thought for the day

"Cast all your anxieties on Him because He cares for you"

St. Peter

Prostate Cancer, Finasteride, Prevention, PSA

What is a man to do? The confusing world of prostate cancer screening and treatment just got more confusing. New joint guidelines produced by the American Society of Clinical Oncology and the American Urological Association has recommended a certain medication (finasteride) for the prevention of prostate cancer in healthy asymptomatic men. Why is this confusing? Isn't prevention a good thing? I want to talk a bit about prostate cancer and the conundrums associated with it.

There are some things that we do know. Prostate cancer is the second leading cause of cancer death in men after lung cancer. It occupies the same place as breast cancer does in women. More people die of colorectal cancer than either prostate or breast cancer but that is referring to men and women together. Approximately 186,000 men in the United States are diagnosed with prostate cancer each year and in that year approximately 30, 000 men will die of it. Prostate cancer dispropotionally affects black men more that whites or other ethnic groups. Prostate cancer is a disease of middle aged to old men usually first diagnosed in those over 50 years old although there a a number of cases in men in their 40's, again dispropotionally more often in black men. Prostate cancer does have a genetic component sometimes but most of the time the causes are unknown. Prostate cancer is curable either by surgery or radiation in the early stages but once locally advanced beyond the wall of the prostate gland is universally fatal as there is no effective chemotherapy. There are treatments, but they are only palliative, not curable

A recommendation for preventive chemotherapy then is big news. But there is till controversy about screening for prostate cancer. The American Urological Association (AUA) has now recommended this preventive treatment but this recommendation comes with a caveat. It is only for those men who have been screened by a blood test for prostate - specific - antigen (PSA) which is a tumor marker and is used for detecting and diagnosing prostate cancer. The new guidelines are for men whose PSA value is 3.0ng/ml or lower. Yet the American Urological Association has not come out with a clear recommendation for men to be screened in the first place! No major cancer group or physician group has come out and actually made a recommendation for routine prostate cancer screening and like the others the AUA is still sitting on the fence despite the high numbers of prostate cancer deaths per year. Confusing?
I will explain more tomorrow.

Thought for the day

"One prostate cancer death per year is one death too many".

The National Prostate Cancer Coalition