[Primary lung cancer with myocardial metastasis mimicking acute myocardial infarction]

A 78-year-old man was admitted to our hospital because of chest and back pain. Fourteen months previously his chest X-ray showed a tumor shadow with cavitation in the left middle field. On admission cardiomegaly was found. Chest CT without contrast enhancement did not detect an intra-myocardial tumor. The electrocardiogram and serological examination suggested acute onset of myocardial infarction. However, emergency coronary angiography detected neither significant stenosis nor occlusion. Thereafter, chest CT with contrast medium demonstrated an intra-myocardial tumor. There wes no pericardial effusion. We clinically diagnosed a myocardial tumor metastatic from lung cancer. He received symptomatic treatment, but died on the 31st hospital day. Autopsy revealed that most of the myocardium had been replaced by lung cancer cells. They did not invading the pericardium directly. These findings supported the clinical diagnosis that myocardial tumor was hematogenous metastasis from lung cancer.