Background: Histopathologic characteristics and optimal treatment modality for superficial esophageal cancer were reevaluated on the basis of 2418 patients from 143 institutions through a nationwide questionnaire to the members of the Japanese Society for Esophageal Diseases.
Methods: A questionnaire was designed for patients with preoperatively untreated superficial cancer of the esophagus who had undergone either surgical or endoscopic treatment between January 1, 1990, and December 30, 1994. Mucosal cancer and submucosal cancer were divided into three subclasses according to the criteria formulated by the Society.
Results: The incidence of positive lymphatic invasion or lymph node metastases tended to increase markedly as cancer infiltrates reached the lamina muscularis mucosa. The majority of the cases with 0-I or 0-III components were submucosal cancer. The indication of endoscopic mucosal resection (EMR) was limited to mucosal 1 and mucosal 2 superficial cancer in 76% of the institutions surveyed. Tumors measuring 2 cm or more in diameter were resected piecemeal in 94% of patients. Complications of EMR, including perforation, stenosis, and hemorrhage, were observed in approximately 6.8% of patients. Almost all patients with mucosal 1 or mucosal 2 cancer are still alive. There was no significant difference in prognosis between mucosal 3 cancer and mucosal 1 or mucosal 2 cancer, but submucosal 1 cancer showed worse prognosis than mucosal cancer.
Conclusions: Local resection of cancer lesions is regarded as the treatment of choice against the superficial esophageal cancers limited to the lamina propria mucosae. Further study is advocated to define the treatment strategy against mucosal 3 or submucosal 1 cancer.