Does obesity make a difference in detecting prostate cancer?
San Antonio (Jan. 31, 2005) – A study by researchers from The University of Texas Health Science Center at San Antonio raises the possibility that the most common test for prostate cancer might be of less benefit to men who are overweight or obese.
Ian M. Thompson Jr., M.D., professor and chair of the department of urology and the Henry B and Edna Smith Dielmann Memorial Chair at the Health Science Center, and Jacques G. Baillargeon, Ph.D., associate professor with the Center for Epidemiology and Biostatistics at the Health Science Center, are among the authors on a study of the relationship between body mass index (BMI) and the prostate-specific antigen (PSA) test. The study in 2,779 men showed that PSA values were lower as BMI increased. The findings were reported in the journal CANCER.
Some researchers theorize that obese men might have elevated hormone levels, possibly explaining their lower PSA scores. An alternative theory, studied by the Health Science Center team, is that PSA may be less sensitive in obese men. This is important because it might mean that obese men are having their cancers diagnosed later, resulting in poorer overall survival.
“The paper shows that PSA doesn’t work as well in overweight and obese men because it gives too low a reading, potentially causing prostate cancers to be missed,” Dr. Thompson said. The epidemiological study was part of the San Antonio Center of Biomarkers of Risk (SABOR) study, which includes a large number of Hispanic men.
The study made headlines from coast to coast and overseas. Major news organizations that quoted Dr. Thompson included The Associated Press, Reuters and The New York Times.
Dr. Thompson also leads the Cancer Prevention and Population Science (CPPS) program of the San Antonio Cancer Institute (SACI), an NCI-designated Clinical Cancer Center that is a partnership between the Health Science Center and the Cancer Therapy and Research Center in San Antonio. One of the goals of the CPPS program is to improve survival rates among African Americans and other men who are at higher risk for prostate cancer.
Dr. Baillargeon also is a SACI member.