An extensive morphological and comparative study of clinically early and obvious squamous cell carcinoma of the esophagus.

Squamous cell carcinoma of the esophagus appears mainly as an isolated tumor, frequently diagnosed in its latest stage. However, current advances in endoscopy, systematically used for high risk subjects, allow the detection of very early lesions such as epithelial dysplasia or in situ carcinoma. Twenty-eight squamous cell carcinomas were extensively studied: Group A contained 15 clinically "early cancers"; Group B 12 clinically obvious carcinomas and group C one clinically obvious bifocal carcinoma. All 15 "early cancers" were multicentric and composed of large fields of invasive, microinvasive or in situ carcinoma around which were found epithelial dysplasias of various degrees. Lymph node metastases at surgery were found in 26% of these cases. Obvious squamous cell carcinomas were contiguous with dysplastic areas in 16.6% and with in situ carcinomas in 33% of these cases. Half (50%) had lymph node metastases at surgery. There was no dysplasia or in situ carcinoma around the two main tumors of group C. A comparison between the different morphological features of the three groups leads us to question whether the solitary tumor of the esophagus really represents the final evolution of an early multifocal carcinoma.