Prostate diseases in Lagos, Nigeria: a histologic study with tPSA correlation

To present a 10year retrospective histologic study of prostate diseases in Lagos, Nigeria. The aim is to document the prevalence, histologic pattern, age distribution and PSA values of prostatic diseases.

The materials consisted of slides, paraffin embedded tissue blocks, patients case files and histology request forms of all prostatic biopsies received at the Morbid Anatomy department of Lagos University Teaching Hospital Idi-Araba, Lagos from 1999 to 2008. Each sample represents a different patient.

Prostatic biopsies comprised 3.6 % of all biopsies in LUTH. BPH was the commonest prostatic lesion and accounted for 70.9% of all cases. The age range was 40 to 94 years with a mean of 67 years and a peak age group at 60-69 years. Stromoglandular pattern was the most common histological type of BPH accounting for 72.2 %( 393) of the cases. Malignant tumours constituted 28.9% of all prostatic biopsies. Most (93.7%) of these malignancies were seen in trucut biopsies. Adenocarcinoma accounted for 99.1% of the total 222 malignant tumours. It showed an age range of 40 to 98 years, a mean age of 66 years and peak prevalence in the 60-69 year age group. Gleason score nine was the most frequent (16.8%) in occurrence. Most adenocarcinomas were poorly differentiated (40%). Incidental carcinoma was seen in 4.2% of prostatectomy samples. High grade PIN was seen in 19.1% of adenocarcinoma cases. The most common inflammatory lesion was chronic non-specific prostatitis accounting for 76.4% of all inflammatory lesions. Malignant and benign lesions were accountable for PSA levels of 1 to 49.9ng/ml while values of 50ng/ml and above were seen exclusively in malignant lesions.

Prostatic lesions constitute a significant source of morbidity among adult males in Lagos. Adenocarcinoma is the commonest histologic subtype of prostatic cancer and most are of poorly differentiated variety. Elevated levels of tPSA in Nigerian males may be as a result prostate cancer, BPH or BPH with prostatitis. PSA should in our opinion be used as a component of a strategy integrating multiple diagnostic approaches for prostate cancer screening and not to be used alone in our environment.