Signet-ring-cell adenocarcinoma of the myocardium presenting as persistent pleural effusions.

We report a case of persistent bilateral pleural effusions in a 40-year-old man with echocardiographic findings suggesting constrictive pericarditis. However, this was not supported by cardiac catheterization. The pleural fluid was transudative in nature and was negative for acid-fast bacilli (AFB) and malignancy. Radiographic studies did not define an underlying etiology. Filling defects were found in the subclavian and jugular veins bilaterally but no pulmonary embolus was found on computed tomographic (CT) scan. The patient developed sudden and profound hypoxia and subsequent pulseless electrical activity and expired. At autopsy the myocardium, pericardium, and proximal blood vessels were invaded with signet-ring-cell adenocarcinoma. Another focus of this tumor also was found in the spleen but not in the stomach, suggesting the heart may have been primary. If so, this is the first reported case of primary cardiac signet-ring-cell adenocarcinoma.