Small cell carcinoma of the prostate

Abstract

Primary small cell carcinoma of the prostate gland is a rare disease entity with a poor prognosis. Even more unusual than primary disease is a metastasis from a lung primary (Johnson et al, 1974; Hodge & Carson, 1985). We confine ourselves in this paper to primary disease, which has to be differentiated clinically from a pulmonary metastasis. Primary small cell carcinoma of the prostate has been described as occurring after a diagnosis of adenocarcinoma of the prostate (Schron et al, 1984), as a combination of the two histologies at the time of initial diagnosis (Tetu et al, 1987) or on its own (Sarma & Weilbaecher, 1989).Though it has been suggested that small cell carcinoma of the prostate reflects a terminal aggressive phase of adenocarcinomatous disease (Schron et al, 1984), the occurrence of “pure” small cell carcinoma presents an argument against this in at least a proportion of cases (Tetu et al, 1987; Sarma & Weilbaecher, 1989). The origin of small cell carcinoma of the prostate is not clear. It has been suggested that this malignancy derives from the argyrophil and argentaffin cells found in the normal prostatic epithelium (Wenk et al, 1977). However, Schron et al (1984) noted that the small cell carcinoma in their three patients developed in association with, and during the course of progression of, “normal” prostatic adenocarcinoma.