Prostate Cancer Patients Usually Die of Other Diseases

A new study implies that regularly scheduled prostate specific antigen (PSA) screening has no effect on prostate cancer mortality rates.

Researchers at the U.S. National Cancer Institute (NCI, Rockville, MD, USA), the University of Colorado (Boulder, USA), and other institutions presented the updated findings of the Prostate, Lung, Colorectal, and Ovarian (PLCO) trial, which screened 76,685 men and 78,216 women for prostate, lung, colorectal, and ovarian cancers between 1993 and 2001. The Intervention-arm men received annual PSA tests for SIX years and digital rectal examinations for four AQ years, while the control arm underwent opportunistic screening.

The researchers linked results with the U.S. National Death Index to extend mortality follow-up to a maximum of 19 years. The results revealed 255 deaths from prostate cancer in the intervention arm and 244 deaths in the control arm, a rate ratio (RR) of 1.04. For comparison, the RR for all-cause mortality was 0.977. But according to researchers, the results don't necessarily negate the value of PSA screening, but rather imply that within the data are clues for personalized decisions for subsets of the prostate cancer population. The study was published in the November 2016 issue of Cancer.

"I treated a guy who'd been diagnosed in his 40s; we did surgery, but then a year later he was diagnosed with melanoma. It turned out that at the same time, his sister was diagnosed with triple-negative breast cancer and died within the year,” said study co-author David Crawford, MD, of the University of Colorado Cancer Center. “Being diagnosed with prostate cancer in your 40s is a red flag that there might be a germline mutation to blame, predisposing these men and maybe family members who share the mutation to more aggressive cancers.”

The conventional PSA test for prostate cancer has been used for nearly 30 years and is not specific enough to delineate between malignancies and non-malignant diseases of the prostate, such as benign prostatic hyperplasia (BPH). In fact, the U.S. Preventive Services Task Force (USPSTF, Rockville, MD, USA) claims that evidence suggests the potential harms caused by PSA screening of healthy men as a means of identifying prostate cancer outweigh its potential to save lives, and that routine annual screening should be eliminated in the healthy.

Related Links:
U.S. National Cancer Institute
University of Colorado
U.S. Preventive Services Task Force