Prostate cancer screening with prostate specific antigen in spinal cord injured men

As the spinal cord injured population ages, prostate cancer becomes a more significant cause of potential mortality. Consequently due to various bladder management techniques the validity of standard prostate specific antigen (PSA) screening values in this population must be evaluated. We compared screening PSA values in a large population of spinal cord injured patients with those in age matched, nonspinal cord injured men.

Screening PSA values were obtained using the AxSYM assay (Abbott Laboratories, Abbott Park, Illinois) in 366 spinal cord injured men 40 to 79 years old. In those with PSA elevated to greater than 4 ng./ml. who consented to further evaluation standard sextant needle biopsy of the prostate were performed under transrectal ultrasound guidance. Data were compared with data on 371 randomly selected, age matched controls from the Baylor College of Medicine community screening program database of more than 19,000 patient-tests. Analysis was performed with the unpaired Student t test.

When we divided patients 40 to 80 years old into 4 age groups by decade and compared them with normal controls by decade, there was no statistically significant difference in mean PSA in the 2 groups. Of 18 spinal cord injured patients with PSA greater than 4 ng./ml. 12 underwent transrectal ultrasound guided needle biopsy of the prostate and 6 refused further evaluation. Five of these biopsies (1.3% overall) were positive and 7 were negative for adenocarcinoma.

As in healthy men, PSA and digital rectal examination can be performed in spinal cord injured men to screen for prostate cancer. None of the various bladder management techniques in these cases seemed to affect screening results.