Immunotherapies move closer to clinical application

May 15, 2005

Urologists treating patients with advanced prostate cancer should anticipate a number of advances this year and next. They will also need to anticipate some of the challenges these advances will create, according to Paul F. Schellhammer, MD, program director of the Virginia Prostate Center and professor of urology at Eastern Virginia Medical School, Norfolk.

Urologists treating patients with advanced prostate cancer should anticipate a number of advances this year and next. They will also need to anticipate some of the challenges these advances will create, according to Paul F. Schellhammer, MD, program director of the Virginia Prostate Center and professor of urology at Eastern Virginia Medical School, Norfolk.

"There is increasing recognition that even advanced metastatic disease is heterogenous and that one-size therapy does not fit all patients. The challenge is to identify subgroups and prognostic factors and maybe create proteonomic and genotypic profiles that will allow the application of specific therapies that will benefit these groups," Dr. Schellhammer said.

Intermittent androgen blockade He called attention to several studies to be presented at the upcoming AUA annual meeting that point to new directions in treating advanced disease.

One of these is a European Organization for Research and Treatment of Cancer (EORTC) study of more than 300 patients showing that intermittent androgen blockade as compared with continuous blockade does not diminish survival but does have a significant beneficial effect on quality-of-life parameters.

"It looks like you can significantly decrease the amount of therapy, in that patients can spend 50% of time off therapy and in some situations as much as 80% of time off therapy. I think that is important information, and we are going to hear a lot more about it," Dr. Schellhammer said.

He noted several studies demonstrating the effects of androgen deprivation therapy on bone structure. These studies showed that as little as 3 months of therapy can have deleterious effects on bone mineral density and that the therapy also impacts vitality/hormonal and sexual quality of life in as little as 2 months.

"But the rapid bone loss can be reversed or at least ameliorated by administration of vitamin D and calcium and, when necessary, bisphosphonates. This should become a common practice," said Dr. Schellhammer.

Data will be presented from a phase II trial showing that adjuvant docetaxel for prostatectomy patients at high risk for recurrence is well tolerated and merits a phase III trial.

"This is a prelude to what we are going to see in the way of treatments for high-risk patients, namely adjuvant and neoadjuvant chemotherapy," Dr. Schellhammer said.

Further into the future there will be a drive to categorize localized prostate cancer to determine if observation or active therapy is appropriate, he speculated. The recent finding that many men have prostate cancer at even very low PSA levels will lower biopsy cut points. This, with the increase to 10 to 12 or more biopsy core procurement, will increase the diagnostic yield, he said.