Histomorphological Characteristics and Distribution of Prostatic Carcinoma Foci Using Multiple Site-Specific Labelled Core Biopsies in a tertiary Hospital in Southwestern Nigeria

Background and Objective: There are many evolving prostatic biopsy sampling techniques aimed at improving diagnostic accuracy, localization, prognostication and dictating prostate cancer treatment options. This study analysed the histomorphology, spatial distribution and prognostic implications of site-specific core biopsies of the prostate gland.
Methods: Double-sextant prostate biopsy cores, representing the medial and lateral aspects of the left and right apices, mid-gland and bases of the glands, were microscopically examined prospectively over an 18-month period. These were obtained by transrectal ultrasound guidance. H&E stained slides were examined for the presence, volume, Gleason score and ISUP grade-group of cancer.
Results: Ninety-one patients aged 48 to 88 years (median age 70 years) were seen. In 68.1% of cases all anatomical zones of an examined prostate gland (apices, mid-gland and bases) had cancer. Overall, the apical region of the prostate gland had cancer in 35.6% of cases, the mid-gland portion 33.8% of the time while the basal region was positive in 30.6% of the cases. Tumour was restricted to mid-gland in 5.5% of cases, the apex in 4.4%, whilst it was restricted to the base in 2.2% of the cases. At least a core from all sextant biopsy sites had cancer in 42.9% of cases. Carcinoma volume was least in basally located cancers. ISUP grade group 5 was most frequently seen and grade group 2 was the least seen.
Conclusion: Prostatic carcinomas in our region have poor prognostic indicators such as poor differentiation, high tumour volume, and in most cases involves biopsy cores from all anatomical zones of the prostate.