Pathological profile of low-grade prostate cancer in an African cohort

Abstract

Background: Prostate cancer is the most common cancer among Nigerian males. The majority of cases are of intermediate to high histological grade; nonetheless, low-grade prostate cancers (LGPCa) are clinical significant because these are more likely to be amenable to surgical treatment and a cure. As such, these tumors require clinical decision-making regarding pursuing active surveillance or radical surgery in affected patients. Yet, there is limited documented information on the characteristics of LGPCa in African males. Aim: This study aimed to describe the prevalence and pathological profile of LGPCa among prostate cancer cases diagnosed in African patients at our hospital over a 4-year period (2016–2019). Materials and Methods: Data were derived from departmental materials and files. All patients were of African descent. Cases diagnosed at Gleason scores 3 + 3 = 6 and 3 + 4 = 7 were included in this study. Data obtained included age, histological diagnosis, and prostate specific antigen (PSA) level at diagnosis. Frequencies and associations were derived. Findings: Material for diagnosis was obtained predominantly from sextant biopsies (58.7%). There were a total number of 371 cases diagnosed as prostate cancer during the review period with a mean age of 69.5 ± 8 years, and a predominance of patients in the seventh decade. Low-grade cancer was seen in 97 (26.2%) of cases. Cases diagnosed as Gleason score 3 + 3 = 6 accounted for 46.4% of low-grade cancers, while Gleason score 3 + 4 = 7 accounted for 53.6% of these tumors. The mean age of patients was 71 ± 8 years (range of 50–89 years). Patients were aged 70–79 years predominantly. The median PSA at diagnosis was 58 ng/mL (range 5.2–9030 ng/mL). Most (81.1%) patients had PSA values >20 ng/mL at diagnosis. Conclusion: LGPCa account for about a quarter of prostate cancers seen. Gleason score 3 + 4 tumors showed higher average tumor volumes compared to Gleason score 3 + 3 tumors. Most Nigerian patients with LGPCa presented with pretreatment PSA levels (>20 ng/mL) and decisions regarding active surveillance should be approached with caution within the African context.