AIM: To analyze the clinical manifestations, pathological features and treatment of primary small cell carcinoma (SCC)of the esophagus and to review the literature on this entity.METHODS: The records of 9 patients with primary esophageal small cell carcinoma were examined and the demographic data, presenting symptoms, methods of tumor diagnosis, and types of treatment given, response to treatment, pathologic findings, and clinical outcome were reviewed. Features of mixed patts of histological differentiation and lymph node metastases were specifically sought.RESULTS: All the patients reported dysphagia, weight loss and chest pain as the initial symptoms. In 5 cases the tumors were located in the mid-esophagus, 3 cases in the lower third of the esophagus and 1 case in the upper third.The average length of esophageal involvement was 5 cm.They underwent radical resection, regional lymph node clearance and esophageal-stomach anastomosis in thorax or at neck. Two patients had a stage Ⅱa disease, five had a stage Ⅱb disease, and the other two had a stage Ⅲdisease of Intational Union Contrele Cancer (UICC). All of them were histologically and immunohistochemically confirmed SCC of esophagus. Immunohistochemical staining for neuron-specific enolase (NSE), synaptophsin (Syn) and chromogranin A exhibited strong immunoreactivity in all specimens. Three of the nine resected specimens showed foci of squamous cell carcinoma in situ. Metastasis was present in 7 of 9 adjacent lymph nodes. All the patients survived the operations and made an uneventful postoperative recovery. They received adjuvant systemic chemotherapy and local radiation therapy after discharge. During followup, three patients developed multiple liver, brain, lung and bone metastases and died between 5 and 18 mo after the diagnosis. Three patients developed widespread metastasis disease and died between 18 and 37 mo after the diagnosis.There was no local tumor recurrence in these 6 patients.The other three patients were lost during follow-up.CONCLUSION: Primary small cell carcinoma of the esophagus is a rare but very malignant tumor. Radical resection combined with chemotherapy and radiotherapy is helpful in limited stage cases.