Validation of a Topographic-Anatomic Subclassification for Adenocarcinoma of the GE Junction (GEJ)
EG Demicco, AB Farris, B Agbor-Etang, J Fukuoka, D Daives, M Snimizu, HA Gaissert, M Mino-Kenudson. Massachusetts General Hospital, Boston; Emory University, Atlanta; Toyama University Hospital, Toyama, Japan; Saitama Medical University, Saitama, Japan
Background: The incidence of adenocarcinoma of the GEJ is increasing more rapidly than any other cancer in the US. Due to the location, staging and treatment for GEJ tumors varies among institutions. The Siewert classification system differentiates between adenocarcinoma of the esophagus (type 1) and that of "cardia" (type 2). The aim of this study was to evaluate whether there was a difference in biologic properties between the 2 types.
Design: We evaluated 149 untreated GEJ type 1 (n=49) and type 2 (n=100) tumors consecutively resected between 2000 and 2008. Demographic data, clinical and/or pathologic evidence of BE, tumor stage, tumor histology (adenosquamous cell carcinoma [AdSq], conventional adenocarcinoma [Ad], mucinous/signet ring cells [muc], medullary/undifferentiated [med], heterogenous [mix]) and outcome were compared between the 2 types. A subset of cases with available blocks (type 1: 40, type 2: 74) was examined by immunohistochemistry using tissue microarray and classified into 4 mucin phenotypes (intestinal [I], gastric [G], combined intestinal and gastric [M], and null [N]).
Results: Type 1 was more likely associated with male gender (p = 0.060), BE background (p = 0.00072) and mixed mucin phenotype (p = 0.028) (Table 1).
|Type 1 (n=49)||Type 2 (n=100)|
|Age (yrs)||65.7 +/- 11.1||66.0 +/- 10.7|
|BE||42 (89%)b||58 (58%)b|
|Tumor size (cm)||4.2 +/- 2.1||3.9 +/- 2.2|