Thrombocytopenia recovered by surgical resection of a myxoma

Myxoma is the most common primary cardiac neoplasm, and causes a variety of symptoms, including hematological disorder. An 82-year-old man with anorexia was diagnosed with a gastrointestinal stromal tumor. Computed tomography and echocardiography showed a 2-cm tumor in the left atrium. The patient had a history of lung and skin sarcoidosis, and interstitial pneumonia. Laboratory examination showed thrombocytopenia with a platelet count of 23×103/μL and elevation of IgA and platelet-associated IgG (PAIgG). We suspected that the thrombocytopenia was caused by the left atrial tumor. He successfully underwent resection of the tumor with cardiopulmonary bypass. The platelet count increased to 166×103/μL after surgery. Pathological examination showed Alcian blue staining of the extracellular and intracellular matrix, suggesting a mucopolysaccharide matrix. Immunohistochemical examination of the tumor revealed expression of CD31, CD34, and calretinin, which was consistent with a myxoma. The PAIgG level decreased to the normal range at 36days postoperatively. Thrombocytopenia is a relatively rare finding in patients with myxomas. However, in addition to mobility of the mass, thrombocytopenia should be kept in mind as an indication for surgery.