Further studies on the musculo-fibrous anomaly of the Barrett's mucosa in esophageal carcinomas.

A total of 50 esophagi with carcinoma were reviewed for the presence of histological changes in the subepithelial tissues of the Barrett's mucosa. Those changes consisted in the thickening of the muscularis mucosae, the presence of muscle fibres in the lamina propria mucosae, fibrosis of the submucosa and sometimes total obliteration of the subepithelial tissues by collagen-rich sclerosis. Those changes have been connoted as "musculo-fibrous anomaly". Barrett's mucosa was present in all 18 specimens with adenocarcinoma and in 13 of the remaining 32 specimens with squamous cell carcinoma. Musculo-fibrous anomaly of the Barrett's mucosa occurred in all 18 specimens with adenocarcinoma and in 10 of the 13 specimens with a concomitantly growing squamous cell carcinoma. Esophageal and metaplastic glands were surrounded, compressed and deformed by the fibrotic tissue. The histological changes described explain the difficulties in the differential diagnosis--in biopsy specimens--between normal glands or glands with dysplastic changes "trapped" in the collagen-rich fibrotic tissue and true invasive adenocarcinoma of the Barrett's esophagus.