by Gila Reckess
School of Medicine researchers have shown that a technique used to measure tumor size allows surgeons to evaluate the chance for progression of prostate cancer after surgical removal of the prostate gland. The findings are published in the Sept. 15 issue of the journal Cancer.
Unlike breast cancers, prostate cancers often are difficult to locate and measure, even after the prostate gland has been removed. Because the tumor usually does not form a mass that is easily seen, its size can be difficult to ascertain.
Tumor size appears to be a sign of how aggressive the prostate cancer is. Determining tumor size can help physicians determine a patient's prognosis and the best course of treatment.
At present, researchers use computer-assisted imaging tools to measure tumor volume. This is the best accepted method of studying the size of the elusive mass. But image analysis is expensive and time consuming. Therefore, it is performed only in research settings.
Peter A. Humphrey, M.D., Ph.D., associate professor of pathology, of immunology and of surgery, and his colleagues have shown that a simple method of examining prostate tissue provides an inexpensive, effective alternative that easily can be used in hospitals around the country. This method is routinely used in other procedures. However, the present study provides the first evidence of its effectiveness when applied after radical prostate surgery in which the entire gland is removed.
Researchers evaluated 595 men with prostate cancer who underwent surgery between January 1993 and December 1997. After the prostate gland was removed, surgical pathologists looked at the tissue under a microscope and visually estimated the percentage of tumor cells present in each sample. The researchers also conducted follow-up exams every six months.
Humphrey and colleagues determined that those patients whom they identified with a higher percentage of cancer cells in their prostate glands were more likely to have a recurrence of the disease in the future.
"Other techniques are good for research, but this one can be used in routine practice," Humphrey said. "It will help physicians determine the risk for recurrence. But the key practical ramification of this is the consideration of future treatment."
With more information about the tumor, physicians can determine the best treatment option for each individual patient.