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Primary uncommon malignant tumors of the esophagus: an analysis of 30 cases.

BACKGROUND
Uncommon malignant tumors of the esophagus are defined as any histological type of malignant esophageal tumors other than the typical squamous cell carcinoma. Their biological characteristics remain obscure because of their rarity. Thus, this is a retrospective review of patients here with uncommon esophageal cancers in an attempt to evaluate their prognostic factors and proper therapeutic modalities.


METHODS
Among 1,674 patients with esophageal cancers, only 30 (1.8%) with uncommon esophageal cancers were collected between 1977 and 1992. The clinical parameters for evaluation consisted of age, sex, histological type, location, staging and a variety of therapeutic management techniques and their results.


RESULTS
Histologically, there were 10 adenocarcinomas, 7 small cell carcinomas, 6 adenosquamous carcinomas, 3 carcinosarcomas, 1 mucoepidermoid carcinoma, 1 adenoid cystic carcinoma, 1 fibrosarcoma, and 1 basal cell carcinoma. The mean age was 65.8 years, ranging from 46 to 85 years. Upon admission to hospital, the most common clinical symptoms included dysphagia, body weight loss and substernal pain. The tumor staging, according to TNM classification was evaluated as follows: Stage I: 13.3%, Stage II: 46.7%, Stage III: 16.9%, Stage IV: 23.3%. The middle third thoracic esophagus was the most common location of tumor occurrence. Overall one-year, two-year, and five-year survival rates were 39.3%, 21.4%, and 10.7% respectively. These results were as poor as those of squamous cell carcinoma. However, the patients with Stage I and Stage II tumors (mean, 23.8 months) had significantly better survivals than those with Stage III and Stage IV (mean, 3.9 months). Furthermore, if the tumor was resectable, the patients undergoing esophagectomy had much better one-year and two-year survival rates than those without esophagectomy (p < 0.01). In addition, patients with small cell carcinoma seemed to have worse treatment outcome than those with other histological types of tumors.


CONCLUSIONS
These results suggested that key factors contributing to prognosis included tumor staging as well as respectability. Thus, it is recommended that, with early detection and diagnosis, esophagectomy might be the treatment-of-choice in managing these uncommon esophageal malignancies. Adjuvant therapy including irradiation and chemotherapy may be helpful, particular for small cell carcinoma.