|
By Lucy Williams, Ivanhoe Health Correspondent
ORLANDO, Fla. (Ivanhoe Newswire) -- Current prostate cancer screening may be insufficient for heavyset men. Biopsy results often underestimate cancer aggression in overweight and obese men, recent research reveals.
Prostate cancer patients typically undergo biopsy to determine the severity of their disease. Biopsy plays a critical role in guiding cancer treatment decisions. But misleading biopsy results may prevent overweight men from receiving treatment that is aggressive enough to fit their needs.
In a new study, overweight prostate cancer patients who appeared to have low-grade cancer based on biopsy results were more likely to have higher-grade, aggressive cancer when the prostate was removed.
"We looked at the grade, which is a sign of how aggressive the cancer is, and compared the initial biopsy versus what we actually found when we took the patient to surgery and took out the prostate," study lead Stephen Freedland, M.D., an assistant professor in the Division of Urology at Duke University Medical Center in Durham, N.C., told Ivanhoe. "We're finding when we take out the prostate, the cancer in obese men is a little bit more aggressive than the biopsy would have led us to believe."
Researchers compared the biopsy grade to the cancer grade following radical prostatectomy, which is the removal of the prostate. In 1,113 men who underwent radical prostatectomy between 1996 and 2005 within the Shared Equal Access Regional Cancer Hospital database, 299 men, or 27 percent, had more severe cancer than suggested by biopsy. In 123 patients, or 11 percent, cancer diagnosis was actually less severe.
More severe cancer was associated with the following conditions:
- Higher prostate-specific antigen (PSA) levels
- More biopsy cores with cancer
- Obesity
- Downgraded diagnoses were associated with lower PSA levels.
Dr. Freedman said there are two main reasons why biopsies may underestimate the severity of cancer in obese men.
"One, obese men have larger prostates, so when you take samples, you may be more likely to miss something in an obese man that has a bigger prostate," he said. "The more likely thing is obese men have more aggressive cancer, period. Even though you don't detect it in biopsy, your suspicion should be high."
Insufficient biopsy sampling was linked to inaccurate diagnosis and more aggressive cancer.
"If the biopsy was only done with less than eight cores, those patients were a lot more likely to have a higher grade disease despite a lower grade disease on the biopsy," said Dr. Freedland.
The research suggests extensive biopsy sampling and more aggressive treatment may be needed to treat overweight prostate cancer patients.
"The moral of the story is, if the patient's obese, despite having a low-grade cancer and biopsy, we should be concerned that it's a higher-grade cancer. Whether all obese men with low-risk disease should be treated like higher-grade, that's what our data would suggest," he said. "I'm not sure we're ready for that, but that's certainly something we should be thinking about."
This article was reported by Ivanhoe.com, which offers Medical Alerts by e-mail every day of the week. To subscribe, click on: http://www.ivanhoe.com/newsalert/.
Source: Ivanhoe interview with Stephen Freedland, M.D.; UROLOGY, 2007;69:495-499
|
.gif)
