One hundred and one patients with histologically confirmed prostate cancer and 202 hospital controls individually matched by age (+/- 2 years), hospital admittance and place of residence, were interviewed during the period 1990-94 in two towns in central Serbia (Yugoslavia). In an analysis using multivariate logistic regression, the followng factors were significantly related to prostate cancer: (1) occupational physical activity during the year preceding the disease [odds ratio (OR)=3.87, 95% confidence interval (95% CI)=2.09-7.16]; (2) occupational exposure to asbestos, steel, dyes and lacquers, bitumen, pitch, iron, nickel, lead, fertilizer and certain other agents (OR=2.13, 95% CI=1.05-4.32); (3) nephrolithiasis (OR=4.52, 95% CI=1.34-15.30); (4) 'other' diseases in medical history such as chronic bronchitis, chronic rheumatic diseases, hypertension, cardiomyopathy, diabetes mellitus, renal diseases, eye diseases and tuberculosis (OR=3.14, 95% CI=1.56-6.33); (5) a greater number (> or = 3) of brothers (OR=2.08, 95% CI=1.35-3.22); and (6) greater numbers (> or = 8) of sexual partners (OR=2.24, 95% CI=1.13-4.44). Marital status, age at first marriage, educational level, age at first sexual intercourse, frequency of sexual intercourse, venereal diseases, tonsillectomy, appendectomy, hernia inguinale and hydrocele, anthropometric characteristics, smoking history, sport and recreational activities and family history of prostatic neoplasms were not found to be independently related to prostate cancer.