The changing pattern of prostate cancer in Nigerians: current status in the southeastern states

This was a ten-year, hospital-based retrospective study for the incidence and clinical pattern of prostate cancer in southeastern Nigeria. Clinical information extracted from the files included the TNM stage, histo-pathological grading, level of prostatic acid phosphatase (PAP), mode of presentation and clinical and biochemical response to intravenous and oral diethylstilboestrol diphosphate (Honvan)/ orchidectomy. There were 145 patients, mean age 66.6 + 9.8 years, giving an incidence of 61.3 per 10(5), with 54% under 70 years. Most patients (81.4%) presented late, with 62% metastatic. Over 98% were adenocarcinomas, 77% of which were moderate to well-differentiated cancers. PAP was elevated in 109 patients (75%), (representing 92% of all advanced tumours), and normal in 36 (25%). Forty-two percent of poorly differentiated cancers had normal levels of PAP. Most patients presented with urinary retention (56%), prostatism (44%), anaemia (41%), recurrent UTI (35%), bone pains (20%), haematuria (18%), backache (16%) and paraplegia (6%). Nearly 79% responded to treatment with lowered PAP levels and improved quality of life, within a mean of 26.3+/-13.8 months (range 5-78); objective 81 (58%), subjective 32 (23%), no response 27 (19%). Among paraplegics, 78% had full, and 22% had partial motor recovery. Patients with poorly differentiated cancers had only a 33% two-year survival rate. This study confirmed an upward, though moderate trend in the incidence of prostate cancer in Nigeria. The use of PAP instead of PSA as the tumor marker, a local diet with high fish content but lower animal fat, and poor hospital access may account for the lower incidence in the southeast. Poor health education may account for the high rate of late presentations.