The Prognosis of Small Pancreatic Adenocarcinoma-Is It a Real Early Pancreatic Cancer?

Abstract

Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal malignant cancers, ranks fifth in mortality related to cancer worldwide and tenth in Taiwan with a 5-year survival rate after resection ranging from 10 to 29%. Improvement of survival needs diagnosis of early pancreatic cancer which can be defined on the basis of resectability, size or curability. In order to define early pancreatic cancer, aiming at better surgical results, early pancreatic cancer has been sought and defined. Small PDAC is defined as a tumor ≤2 cm in size, and it is usually asymptomatic or has only non-specific symptoms. It was previously considered as an early cancer, with its diagnosis based on the TNM and Japan Pancreas Society classification defining a T1 tumor as less than 2 cm in diameter. In recent reports, lymph node metastasis, tumor differentiation, and local infiltration, but not tumor size, were deemed as the independent predictors of PDAC. Hence, small PDAC should not be regarded as an early pancreatic cancer, and aggressive management such as surgery plus postoperative chemotherapy and radiation is justified.