Cardiac relapse of squamous cell carcinoma of the maxillary sinus.

: An unusual case of maxillary sinus carcinoma presenting with heart metastasis is reported. The epicardium, myocardium and endocardium were infiltrated with the tumor, but no evidence of recurrent maxillary sinus carcinoma and other organ metastasis was found. Surgical excision was not possible due to massive invasion of the heart by the tumor mass. The right ventricular inflow tract obstruction was relieved by surgical dilatation.