Small cell neuroendocrine tumors of the prostate account for 1-2% of cases of prostate cancer.
Neuroendocrine cells are found throughout the prostate and can secrete corticotropin, serotonin, chromogranin A, neuron-specific enolase, bombesin, calcitonin, and parathyroid hormone related protein.
Approximately half of the cases express TTF (thyroid transcription factor1), a protein frequently expressed in lung, thyroid cancers and small cell carcinomas.
Up to 50% of cases were associated with acinar- type adenocarcinomas.
About one half of cases present with bladder obstruction and 1/3% would metastatic disease.
PSA not usually expressed in such cancers.
Small cell neuroendocrine cancer may be seen with patients treated with previous hormone therapy for prostate cancer who present with widespread metastatic disease to unusual sites such as soft tissue, omentum, and pericardium.
Frequently associated with widespread metastases to the liver and lungs.
Bone metastases tend to be osteolytic rather than osteoblastic.