[Histochemical study of adenocarcinomatous components in carcinoma of the esophagus]

To comprehend the frequency and clinical features of adenocarcinomatous components in carcinoma of the esophagus, 135 lesions in 128 patients with carcinoma of the esophagus were histochemically and clinicopathologically studied. Mucus-histochemistry, especially mucicarmine staining, revealed mucus-secreting components in 48 lesions (35.6%). This is a much higher rate of esophageal cancers with adenocarcinomatous components than previously reported. Furthermore, no significant clinicopathologic differences were noted between the mucus-stain-positive and -negative groups, except for a higher rate of venous infiltration in the mucus-stain-positive group. Carcinoma of the esophagus with adenocarcinomatous components, particularly mucoepidermoid carcinoma, has generally been considered to arise from the proper esophageal gland or its ductal epithelium. However, certain evidence in this study, such as the mucus-secreting components in mucosal carcinoma and a high incidence of intraepithelial spread, suggested a squamous epithelium origin. Immuno-histochemistry using the peroxidase-antiperoxidase (PAP) technique revealed 49 lesions (36.3%) to be positive for tumor carcinoembryonic antigen (CEA). Tissue CEA was found mostly around mucins and/or glandular structures, and CEA-stain-positive lesions were more prominent in the mucus-stain-positive group, suggesting that CEA in carcinoma of the esophagus originates in the adenocarcinomatous components. Furthermore, the mucus-stain-positive group showed significantly higher rate of patients with pathologic serum CEA levels. Therefore, the serum CEA level is useful for the follow-up patients with mucus-stain-positive carcinoma of the esophagus.