ABSTRACT

An 18-year-old boy presentedwith a 3months' history of progressively worsening breathlessness and peripheral oedema. Therewas no significant family history. Echocardiography demonstrated a 58 mm × 49 mm mass, probably left atrial myxoma with no pericardial effusion and good left ventricular function. Myxoma removal was planned two days after echocardiography evaluation, intraoperatively there was firm vascular mass present in left atrium with involvement of interatrial septum and extending into right pulmonary veins, the mass was encasing aorta and pulmonary artery on lateral and posterior surface with involvement of pericardium anteriorly, so procedure was abandoned after incisional biopsy which was sent for immunohistochemistry and histopathological examination (HPE) (Fig. 1). Post-operative high resolution contrast computerized tomography imaging (Fig. 2) revealed evidence of large, lobulated ill-definedmulticompartment, heterogeneously enhancingmediastinal nodal mass. The mass had non-enhancing necrotic areas within, seen contiguously involving left lower cervical, aorto-pulmonary window, pre-vascular, pre-subcarinal and bilateral hilar regions. This solid seemingly encapsulated mass was adherent to left atrium and appeared to arise from the posterior free wall of the left atrium. A vascular, nonhomogeneousmasswas seen to be densely adherent to the posteriorwall of the left atrium and the coronary sinus. HPE report was suggestive of tumour infiltrating the myocardium which was composed of solid sheets of atypical cells with vesicular nuclei, variably visible small nucleoli, and eosinophilic cytoplasm. Mitoses were seen and there was focal tumour necrosis. An associated brisk lymphocytic infiltrate was present in places. No evidence of gland formation, mucin production, or keratinization was