Occult cardiac lymphoma and sudden death.

A 56-year-old man with no previous medical history collapsed and was not able to be resuscitated. The major findings at autopsy were enlargement of the heart (weight = 527 g) which contained an infiltrating firm, homogeneous tumor in an epicardial location adjacent to the left anterior descending and right coronary arteries, with further extension into the right ventricular outflow tract, the interventricular septum and left ventricular free wall. Sections showed sheets of small lymphoid cells with scattered large lymphocytes amounting to a low-grade follicular non-Hodgkin lymphoma, as tumor cells were CD20, CD10, Bcl 2 and LMO 2 positive. This case demonstrates a very rare cause of sudden and unexpected death that resulted from a low-grade follicular lymphoma in an asymptomatic, immunocompetent individual.