Investigating racial differences in clinical and pathological features of prostate cancer in South African men

Abstract

Introduction: Men with West African ancestry living in Europe and North America are at higher risk of being diagnosed with prostate cancer, are diagnosed at a younger age, and have more severe disease characteristics. Published reports present a conflicting picture of the disease in sub-Saharan Africa. We aimed to study the clinical and pathological features of men undergoing prostate biopsy from different racial backgrounds in South Africa in an attempt to characterise the disease locally. Our hypothesis was that black African men presenting to our service had more severe disease characteristics than other patients.

Methods: All patients who underwent a prostate biopsy at Groote Schuur Hospital, Cape Town from July 2008 to July 2014 were studied. For each patient, data were collected on age, self-assigned race, presenting symptoms, prostate-specific antigen (PSA) level, prostate volume, and histological diagnosis.

Results: A total of 1016 patients were studied. 162 (15.9%) were black and 854 (84.1%) were coloured (mixed ancestry), white, or Asian. Black patients were compared as a group to the coloured, white and Asian patients. The black patients in the series had higher PSA values (mean 167.8 vs 47.7, median 16.4 vs 10.9, p < 0.001), were more likely to be diagnosed with cancer (57.4% vs 44.5%, p = 0.003), were more likely to present with locally advanced cancer (T3/4 16.1% vs 8.9%, p = 0.028), and were more likely to have high grade disease (Gleason ≥ 8 45.2% vs 30.5%, p = 0.011). There was no difference in age, presenting symptoms, or prostate volume.

Conclusion: The black men diagnosed with prostate cancer at Groote Schuur Hospital had significantly worse clinical and pathological characteristics than the non-black men. Interpreting these differences as representative of a more common or aggressive disease among black men is not possible due to study limitations.