Progression of prostate cancer to neuroendocrine cell tumor

Background: The progression to endocrine therapy-resistant prostate cancer is partly due to clonal change to neuroendocrine cell tumor. To elucidate t his pathologic process, the clinical courses of four cases of neuroendocrin e cell tumor that were found at autopsy are reported. Methods: Between 1995 and 1999, autopsies were performed for 20 cases of pr ostate cancer. Lesions predominantly composed of a neuroendocrine cell tumo r (small cell carcinoma) were found in four men. The clinical courses of th ese cases were compared to 16 other, non-neuroendocrine cell tumors (adenoc arcinomas). Results: The outstanding features of the neuroendocrine cell tumors were: ( i) survival was brief after relapse, although the duration of control by em ploying endocrine therapy varied; (ii) the prostate-specific antigen level did not increase after relapse; and (iii) the sites of metastasis were simi lar to those of corm-non adenocarcinomas. Conclusion: The progression to a neuroendocrine cell tumor indicated a poor prognosis and slight (if any) changes in the serum prostate-specific antig en level. This tumor might not appear to respond to any therapeutic attempt .