[Neuroendocrine cancer of the prostate. A series of 6 cases]. / Cancer neuroendocrine de la prostate. A propos de 6 cas.

INTRODUCTION: Neuroendocrine cancer of the prostate (NECP) is a rare entity. Screening for this tumour, although not systematic, may have therapeutic implications. The authors retrospectively evaluated 6 cases of NECP observed in the department between September 1998 and May 2002. MATERIAL AND METHODS: The diagnosis was based on immunohistochemical analysis of biopsy fragments with the presence of marked neuroendocrine differentiation (minimum 50%). Positive staining for anti-Neuron-Specific Enolase (NSE) and anti-Chromogranin A antibodies was observed in 5 and 6 cases, respectively, while anti-PSA antibody labelling was always negative. RESULTS: NECP represented 2.1% of all prostate cancers diagnosed in the department over the same period. Digital rectal examination was abnormal in every case with a median PSA of 9.75 ng/ml (range: 0.25-19.6). Three patients presented metastatic disease at the time of the diagnosis. Four of the 6 patients were urgently admitted to hospital because of acute clinical features. Paroxysmal abdominal pain occurred during the course of the disease in every case with a median of 52 days (range: 22-198) and was initially present in 2 cases. Chemotherapy was performed in 3 cases and palliative therapy was administered in the other cases. A survival difference was observed for patients treated by chemotherapy (13 months versus 4.7). The median survival was 9 months and 14 days. Death occurred in a context of rapid alteration of the general state and renal function. CONCLUSION: NECP has a poor prognosis. Clinical and complementary features guide the diagnosis, which can be confirmed by immunohistochemical analysis, allowing early management based on chemotherapy.