Introduction: Anorectal neuroendocrine small cell carcinomas are rare and frequently difficult to treat.
Exegesis: Two women presented with a fungating tumor located on the upper part of the anal canal. Histology displayed neuron-specific enolase and chromogranin A immunoreactive small cell tumors. A plasmatic neuron-specific enolase secretion was noticed in one case. Tumors were poorly reactive to chemotherapy and irradiation, less than in usual epidermoid anal canal cancer. Evolution was quickly leading to hepatic and pulmonary metastases in both cases.
Conclusion: Anorectal neuroendocrine small cell carcinomas are rare but need to be individualized from epidermoid anal canal tumors owing to their poor prognosis with a frequent occurrence of hepatic and pulmonary metastasis.