January 09 Newsletter Articles

External Beam Radiation for Prostate Cancer Hikes Risk of Secondary Cancers

Naeem Bhojani, MD, of the University of Montreal, Canada and his colleagues studied 10,333 men treated with external beam radiation therapy (EBRT, 4,137 patients) or radical prostatectomy (6,196 patients) and identified men subsequently diagnosed with secondary malignancies. They identified 92 bladder cases. 82 lung cancers, and 228 rectal cancers.

After adjusting for age, baseline comorbidities, and year of treatment, EBRT predisposed to a threefold higher rate of bladder cancer and a nearly twofold higher rate of lung and rectal cancer.

"The increased rate of secondary malignancies after EBRT should be considered in localized prostate cancer treatment decision-making," they conclude.

Renal & Urology News, 23 May 2008

DEFENDING THE PROSTATE CANCER BLOOD TEST

Given rising medical costs, physicians are increasingly urged to practice "evidence-based" medicine. The recently updated guidelines for prostate-specific antigen, or PSA, screening for prostate cancer ["U.S. Panel Questions Prostate Screening," front page, Aug. 5] illustrate the promise but also the pitfalls of incomplete evidence as well as the importance of individual considerations.

I am a general internist, and, in the past three years, I have known two men (not my patients), one in his 80s, the other in his 90s, who were not screened and who developed florid prostate cancer with multiple painful metastases to their bones. The younger man had other health problems, but his cancer responded to hormone treatment that significantly improved the quality of his remaining years. The older man, otherwise perfectly healthy and in full possession of his faculties, died a painful and almost certainly premature death.

Guidelines are designed for groups and are based on probabilities. Prostate cancer is usually a slowly developing disease. If every man over 75 were screened, and everyone who tested positive were treated, we would be likely to spend more money on prostate cancer than it warrants.

However, the PSA test is easy and cheap. For the two men I mentioned, timely testing could have made all the difference.

Caroline Poplin, MD

The Washington Post, 7 August 2008

EXPOSURE TO AGENT ORANGE LINKED TO PROSTATE CANCER IN VIETNAM VETERANS

New research shows that Vietnam War veterans exposed to Agent Orange have greatly increased risks of prostate cancer and even greater risks of getting the most aggressive form of the disease vs. those who were not exposed. The study's findings are the first to link the herbicide with this form of cancer. The research is also the first to utilize a large population of men in their 60s and the PSA test to screen for the disease. The study was released online ahead of print will be published in the September 15 Issue of the journal Cancer.

"While others have linked Agent Orange to cancers such as soft-tissue sarcomas, Hodgkin's disease and nonHodgkin's lymphoma, there is limited evidence so far associating it with prostate cancer," said Karim Chamie, lead author of the study and resident physician with the UC Davis Department of Urology and the VA Northern California Health Care System.

More than 13,000 Vietnam veterans enrolled in the VA Northern California Health Care System were stratified into two groups exposed or not exposed to Agent Orange between 1962 and 1971. Based on medical evaluations conducted years later, the study revealed that twice as many men exposed to Agent Orange developed prostate cancer. In addition, they were diagnosed 2.5 years younger and were nearly four times more likely to present with metastatic disease.

5 August 2008

PROTON RADIATION FAILS TO IMPRESS IN PROSTATE CANCER STUDY

Proton radiation for early prostate cancer had an acceptable tolerability profile but produced little evidence of a "gee whiz" impact to support its cost, according to preliminary results from a phase I/II clinical trial.

Two-thirds of patients had acute genitourinary (GU) or gastrointestinal (GI) toxicity, and a third had late GU/GI toxicity, Anthony Zietman, MD, of Harvard and Massachusetts General hospital, reported at the American Society for Therapeutic Radiology and Oncology meeting(1). Although most of the toxicity was grade 2 in severity, the overall profile provided little reason for enthusiasm.

"The bottom line is that the treatment was safe, it was reasonably well tolerated, but probably no better tolerated than any other form of radiation that we give," Dr. Zietman said. "I think it's true that if I were looking at this data for the first time, I would say, What's the big deal? I didn't see a home run here,'" he added.

1. Zietman AL, et al. Int J Rod/or Oncol Biol Phys 2008; 72(1 Suppl): S77, abstract 169,

MedPage Today, 26 September 2008

IMAGING ADVANCE TRACKS PROSTATE CANCER IN LYMPH NODES

A new imaging technique, based on an engineered version of the common cold virus, may help doctors detect the spread of prostate cancer to the lymph nodes earlier.

This, in turn, could help guide more effective treatment decisions, said the authors of a study published in the July 11 edition of Nature Medicine

"It would represent a treatment advance in patients for whom outcome is not good," study senior author Dr. Lily Wu, a researcher at UCLA's Jonsson Cancer Center, said in a university news release. "This would help improve the prognosis for these patients by letting us find and treat these metastases early. If we can catch the cancer before it invades other organs, we have a butter chance to change the outcomes for these patients."

Patients whose prostate cancer has traveled to their lymph nodes are more likely to have a recurrence. Finding these tiny metastases in the pelvic lymph nodes is key to making future treatment decisions, yet it is also supremely difficult to do with conventional imaging techniques.

Wu and her colleagues engineered a common cold virus armed with a specific "genetic payload" so that it could to travel directly to lymph nodes in mice and to express its payload only in prostate cells.

The payload consists of a protein that can be picked up on PET scans.

Wu and her colleagues next want to combine the imaging technique with treatment, so that a drug contained in the genetic payload could kill the traveling tumor cells.

"I think this is very exciting for many reasons," said Wu. "We now know we can reach these prostate cancer metastases at an earlier stage than before, and we know we can deliver genes to those cancer cells that produce proteins that can be imaged by PET. Now we will find out how effective this genetic toxic payload is in preventing further spread of the cancer to other vital organs."

HealthDay Nears, 15 July 2008