Pancreatic acinar-like adenocarcinoma of the proximal stomach invading the esophagus

The aim of this study was to systematically investigate clinicopathologic features of the recently described pancreatic acinar-like adenocarcinoma of the proximal stomach invading the esophagus (n = 43). Patient median age was 66 years (range, 51-90 years). The male-to-female ratio was 7.6. Grossly, pancreatic acinar-like adenocarcinoma tumors were nonencapsulated with the median size of 5.5 cm (range, 2-10.5). Bormann's types 1 to 4 tumors were in 7%, 9%, 67%, and 16% cases, respectively. Frank necrosis, hemorrhage, and cysts were rare or absent. Lymphovascular (81%), perineural (74%), and lymph node (81%) invasions were more common in the pancreatic acinar-like adenocarcinoma than in the non-pancreatic acinar-like adenocarcinoma (n = 94) groups. Microscopically, pancreatic acinar-like adenocarcinoma tumors showed acinar (78%), micropapillary (12%), microcystic, solid, trabecular, and mixed neuroendocrine or signet ring (33%) patterns of growth. No adenosquamous differentiation was noted in the pancreatic acinar-like adenocarcinoma group. Nuclei were round to oval with thickened nuclear membrane, stippled chromatin, and single prominent nucleoli. Mitotic figures were variable. The cytoplasm was moderate, eosinophilic, finely granular, and diffusely immunoreactive to the α1-chymotrypsin antibody in all cases to various degrees. Tumor stroma was nondesmoplastic, delicate, and fibrovascular. Pancreatic acinar-like adenocarcinoma tumors staged pI, pII, pIII, and pIV were in 2%, 21%, 70%, and 7% of cases, respectively. The median number of follow-up months after surgery was 29. The 2-year survival rate was 67%, lower than that (73%) in the non-pancreatic acinar-like adenocarcinoma group. A worse overall survival trend was found for patients in the pancreatic acinar-like adenocarcinoma than in non-pancreatic acinar-like adenocarcinoma groups, but the difference was not statistically significant. Age older than 75 years and overall pathology stage were independent risk factors.