A unifying concept for periampullary cancer
Introduction: Periampullary adenocarcinomas comprise pancreatic ductal (PDAC), distal bile duct (DBDAC), ampullary (AMPAC) and duodenal (DUOAC) adenocarcinoma. The epithelia of these anatomical structures share a common embryologic origin from the foregut. With steadily increasing numbers of pancreatoduodenectomies over the last decades, pathologists, surgeons and oncologists are more often confronted with the diagnosis of “other than pancreatic” periampullary cancers. The intestinal subtype of AMPAC has been shown to correlate with better prognosis.
Methods: From = 198 cases of periampullary carcinoma with clinical follow-up, evaluation of histological subtype and immunohistochemical staining pattern for CK7, CK20 and CDX2 was done by two experienced pathologists. Routine pathological parameters were included in survival analysis performed with SPSS 17.0.
Results: In univariate analysis, intestinal subtype was associated with better survival in AMPAC, PDAC and DUOAC. The intestinal type of PDAC was not associated with IPMN precursor lesions and could not be reliably diagnosed by immunohistochemical staining pattern alone. Intestinal differentiation and lymph node ratio, but not tumor location were independent predictors of survival when all significant predictor variables from univariate analysis (grade, TNM stage, presence of precursor lesions, surgical margin status, perineural, vascular and lymphatic vessel invasion, CK7 and CDX2 staining pattern) were included in a Cox proportional hazards model.
Conclusion: Intestinal type differentiation of periampullary carcinomas and lymph node ratio are independent prognostic factors not only in AMPAC, but also other periampullary carcinomas like PDAC. Differentiation is more important than tumor location for prognostic stratification in periampullary carcinomas.