==== Front Ann Saudi MedAnn Saudi MedAnnals of Saudi Medicine0256-49470975-4466King Faisal Specialist Hospital and Research Centre 2465856210.5144/0256-4947.2014.84asm-1-84Case ReportA rare cause of left atrial mass: endometrial stromal sarcoma metastasis Ekmekci Ahmet Özcan Kazim Serhan Canga Yigit Karatas Baran From the Department of Cardiology, Siyami Ersek Training and Research Hospital, Istanbul, TurkeyCorrespondence: Dr. Kazim Serhan Ozcan, Department of Cardiology, Siyami Ersek Training and Research Hospital, Tibbiye Caddesi, Uskadar, Istanbul 34087, Turkey, T:+905326742429, F:+902165454736, serhandr@gmail.comJan-Feb 2014 34 1 84 86 Copyright © 2014, Annals of Saudi Medicine2014This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Endometrial stromal sarcomas (ESS) are rare tumors of the uterus. The metastasis of ESS to the cardiac structures is extremely infrequent. Several cases of right-sided heart metastasis have been previously reported. To our knowledge, only one similar case is available in the published studies that presented with recurrent embolic strokes due to left atrial metastasis of ESS. In this report, we describe a 53-year-old woman with endometrial stromal sarcoma; she was referred to our hospital with subacute onset of severe dyspnea and a left atrial mass causing severe mitral stenosis. ==== Body Endometrial stromal sarcomas (ESS) are rare tumors of the uterus accounting for 0.2% to 1% of all uterine malignancies and for approximately 6% to 20% of all uterine sarcomas.1 The earlier division of endometrial stromal sarcomas into low-grade and high-grade categories is no longer considered correct, and the term endometrial stromal sarcomas is now restricted to neoplasms that were formally referred to as low-grade endometrial stromal sarcomas. The most common sites of metastasis are the vagina, pelvis, and peritoneal cavity. Relapses were reported in the brain, lungs, liver, bladder, and bones.2 However, intracardiac metastasis from ESS is extremely rare, and almost all reported metastasis are to the side of the heart with direct invasion of the inferior vena cava. This metastasis presents with signs and symptoms of right ventricular failure. Surgery is the treatment of choice if the patient is symptomatic. To our knowledge, there is only 1 report of left atrial metastasis from ESS, which presented as recurrent embolic strokes.3 We describe the first reported case of left atrial metastasis from ESS via the pulmonary veins, and the patient presented with symptoms and signs of mitral stenosis. CASE A 53-year-old woman was admitted to our emergency department with a 2-month history of dyspnea and palpitation. She was diagnosed with metastatic ESS 2 years ago and was on ifosfamide and doxorubicine chemotherapy. Vital signs were stable with a blood pressure of 130/80 and a heart rate of 90 bpm. Physical examination revealed II/IV diastolic murmur, which is best heard at the apex. Blood chemistry was unremarkable except mild thrombocytopenia and elevated erythrocyte sedimentation rate. The electrocardiogram and chest X-ray were normal. Transthoracic echocardiography (TTE) showed a mass at the edge of the right upper pulmonary vein lying into the left atrium, which had cystic and solid components. During diastole, the cystic portion of the mass was moving into the left ventricle through the mitral orifice and mimicking mitral stenosis (Figure 1). A peak transvalvular gradient of 25 mm Hg (mean gradient of 12 mm Hg) was taken, as seen in severe mitral stenosis. Mitral valve area was calculated as 0.82 cm2 using the pressure half-time method. Pulmonary arterial pressure was measured as 50 mm Hg. Computerized tomography (CT) of the thorax showed a hypodense (7.0×3.2 cm) mass in the left atrium that extended into the left ventricle and pulmonary vein. Multiple metastatic nodular lesions were observed in the pulmonary parenchyma as well. Cardiac magnetic resonance imaging (MRI) confirmed the presence of a tumoral mass rather than a thrombus (Figure 2). Cardiac surgery was planned to remove the mass that was causing severe symptoms, but the patient refused this surgery and was transferred to medical oncology service. She died 6 months later. DISCUSSION Primary cardiac tumors are extremely rare with an inciendometrial dence of 0.02%, and metastatic disease is 20 to 40 times more frequent than primary malignancies of the heart. The most common secondary tumors of the heart originate from leukemia, melanoma, lung cancer, breast cancer, lymphoma, and genitourinary system cancers.4 The majority of tumors are benign. Atrial myxomas are the most common primary cardiac tumors, accounting for 30% to 50% of all primary cardiac tumors, with 75% occurring in the left atrium.5 Left atrial masses can cause two major complications, namely systemic embolism and mitral stenosis. Clinicians must be careful because thrombus can be seen as a left atrial mass in patients with mitral stenosis. Similarly, patients with malignancies are also prone to thrombus formation. In this case, it was necessary to distinguish thrombus and tumoral mass because the treatment strategies are different for the two. If mitral valve is normal and no spontaneous echo contrast formation is present in the left atrium on the TTE, the probability of thrombus is very low. But it should be confirmed with further tests like CT or MRI. ESS was first described by Doran and Locky in 1908. The annual incidence of ESS is approximately 2 per 1 000 000 women. Although they have the propensity for lymphatic and venous invasion, they rarely involve the large vessels or the heart. Spread to the heart is known to occur by direct extension, hematogenous spread, lymphatic spread, and intracavitary extension.6 Most of the reported cases with intracardiac metastasis from ESS simultaneously had intracaval or right-sided heart involvement.7 When the intracardiac metastasis is localized in the right side of the heart, it may produce right-sided heart failure symptoms like pretibial edema, ascites, and hepatomegaly. We did not see these symptoms in our patient because the right atrium and ventricle were normal. Chalmers and Campbell3 reported a case of left atrial mass that caused recurrent embolic strokes in a patient with ESS. To our knowledge, our report is the second case of the left atrial metastasis from ESS, and the first case presenting with symptoms and signs of mitral stenosis that is evoked by metastatic mass. The possible mechanism is hematogenous spread of ESS to the lung, and thereafter, to the pulmonary veins and direct extension from the pulmonary veins into the left atrium. Clinicians should accomplish differential diagnosis of a left atrial mass with further tests like cardiac CT or MRI. Although we could not perform biopsy or surgery to confirm the diagnosis, we considered this as a metastasis from the ESS. As histological examination is considered as the gold standard for the diagnosis, surgical resection must be considered when accurate diagnosis is available. In our case, surgery could not be performed because of the advanced stage of the disease, so a definite diagnosis of the mass could not be confirmed. However, the patient had undergone metastatic ESS diagnosis for two years, and the left atrial mass was interpreted as metastasis in cardiac CT and MRI thus supporting our diagnosis of metastasis from ESS. Figure 1 Transthoracic long-axis view showing the cystic component of the mass (black arrows), which is moving into the left ventricle during diastole. Figure 2 Cardiac magnetic resonance imaging revealed a left atrial mass (black arrows) extending directly into the left atrium through the pulmonary vein, which had a cystic component moving into the left ventricle (white arrows). LA: Left atrium, LV: Left ventricle, RA: Right atrium, RV: Right Ventricle. ==== Refs REFERENCES 1 Koss LG Spiro RH Brunschwing A Endometrial stromal sarcoma Surg Gynecol Obstet Invest 1965 121 531 537 2 Yokoyama Y Ono Y Sakamoto T Asymptomatic intracardiac metastasis from a low-grade endometrial stromal sarcoma with successful surgical resection Gynecol Oncol 2004 92 999 1001 14984976 3 Chalmers N Campbell IW Left atrial metastasis presenting as recurrent embolic strokes Br Heart J 1987 58 170 172 3620256 4 Hoffmann U Globits S Frank H Cardiac and paracardiac masses. 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