HISTOPATHOLOGIC CHANGES SEEN IN ESOPHAGECTOMY SPECIMENS FROM THE HIGH-RISK REGION OF LINXIAN, CHINA - POTENTIAL CLUES TO AN ETIOLOGIC EXPOSURE

Esophageal cancer is one of the most fatal cancers worldwide and is ch aracterized by great variation in rates among different populations. L inxian, a county in Henan Province, located in north-central China, ha s one of the highest rates of esophageal squamous cell carcinoma in th e world. Most squamous cell carcinomas in low-risk populations are att ributable to alcohol and tobacco consumption, but the causative agents in high-risk populations are less clear. The prevention and treatment of esophageal cancer in high-risk regions, such as Linxian, are limit ed by our inability to identify these agent(s). During a preliminary h istological review the authors noticed characteristic findings in the arteries, nerves, and lymph nodes of esophagectomy specimens from Linx ian and wondered whether these findings might offer clues to the cause of squamous cell carcinoma (eg, polycyclic aromatic hydrocarbon expos ure) in the Linxian population. The purpose of this study was to repor t these previously undescribed histopathologic changes and to compare their presence and severity with those found in esophageal squamous ce ll carcinomas and adenocarcinomas from a lower-risk population in the United States. Forty esophagectomies were reviewed, including 13 squam ous cell carcinomas from Linxian and 21 squamous cell carcinomas and s ix adenocarcinomas from the United States. The presence and severity o f arteriosclerosis and myxoid degeneration of nerves and the presence of anthracosis in periesophageal lymph nodes were recorded. The preval ence and severity of these findings in the three groups of esophagecto mies were compared. The esophageal squamous cell carcinomas from Linxi an, China, had a higher prevalence of arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes than the squamo us cell carcinomas from the United States (Wilcoxon test, P<.04 for al l comparisons). There were also significant differences in the prevale nce of arteriosclerotic vessels and anthracotic lymph nodes between th e esophageal squamous cell carcinomas from Linxian and the adenocarcin omas from the United States. Arteriosclerosis and the myxoid degenerat ion were significantly more severe in the esophageal squamous cell car cinomas from Linxian than in the esophageal squamous cell carcinomas o r adenocarcinomas from the United States (Mantel trend test, P <.006 f or all comparisons). Arteriosclerotic vessels, nerves with myxoid dege neration, and anthracotic lymph nodes can be seen in association with esophageal squamous cell carcinomas from the high-risk region of Linxi an, China. These changes appear to be more prevalent and severe than t hose seen in association with esophageal squamous cell carcinomas or a denocarcinomas from a low-risk population in the United States. These characteristic changes may be causatively significant and may represen t histological evidence of high-level environmental exposure to polycy clic aromatic hydrocarbons. Copyright (C) 1998 by W.B. Saunders Compan y.