[598] Gastroesophageal Junctional Carcinomas in Chinese Patients Show Distinct Clinicopathologic Features

Q Huang, XS Fan, AT Agoston, AN Feng, G Lauwers, RD Odze, LH Zhang. Boston VA Healthcare System, Boston; Nanjing Drum Tower Hospital, Nanjing, China; Brigham and Women's Hospital, Boston; Massachusetts General Hospital, Boston

Background: The pathogenesis of carcinomas involving the gastroesophageal junction (GEJ) is poorly understood. In the United States (US), most authorities believe that GEJ carcinomas are related to Barrett esophagus (BE). However, in China, BE is infrequent but GEJ carcinomas are common. The aim of this study was to investigate and compare the clinicopathologic features of GEJ carcinomas that developed in patients in the US (Caucasians) versus China.
Design: Routinely processed tissue slides of untreated GEJ carcinoma resection specimens were retrieved from 29 US and 35 Chinese patients. Clinical information and histological features of GEJ carcinomas were reviewed and compared between the two patient groups. GEJ carcinoma was defined as a tumor with its epicenter within 2.5 cm of the GEJ.
Results: Compared to US patients, GEJ carcinomas in Chinese patients occurred at a younger age (63 vs 68 years; p<0.05) and were larger in size (mean size: 5 vs 3cm; p<0.01). All GEJ tumors were adenocarcinomas (100%) in US patients, but tumors in Chinese patients were adenocarcinoma in 60%, acinar cell carcinoma in 9%, adenosquamous carcinoma in 18%, and colloid-signet ring cell carcinoma in 11%. BE was identified in 92% of US patients, but only in 7% of Chinese cases (p<0.0001). Furthermore, adjacent gastric mucosa showed intestinal metaplasia and dysplasia in 51% and 43% of Chinese patients, respectively, which were significantly higher values than those found in US patients (10% and 3%, respectively) (p<0.0001).
Conclusions: GEJ carcinomas that develop in Chinese patients are clinically and pathologically different from those in US patients. These data may indicate different pathogenetic mechanisms for GEJ carcinomas in China compared to the US.
Category: Gastrointestinal

Monday, March 9, 2009 11:15 AM

Platform Session: Section C, Monday Morning