Hernia of Morgagni's foramen presenting as asymptomatic pleural mass

An asymptomatic 64-year-old black man presented with an enlarging left pleural mass. Preoperative evaluation failed to reveal an etiology. At thoractomy omental fat was found along the diaphragm, extending to the left costophrenic angle, and protruding through a hernia of Morgagni's foramen. The omentum was replaced into the abdomen and the defect was repaired.