Primary pulmonary enteric adenocarcinoma

Pulmonary enteric adenocarcinoma (PEAC) or pulmonary adenocarcinoma with enteric differentiation (PAED) is an extremely rare variant of primary invasive adenocarcinoma of the lung. It has morphological and immunohistochemical profiles overlapping with that of colorectal carcinoma. Due to this, it is difficult to diagnose and requires a definite exclusion of a colonic primary.


It is usually defined as a primary pulmonary adenocarcinoma where the enteric component exceeds 50% and with an expression of at least 1 immunohistochemical marker of enteric differentiation.