Mediastinal Rhabdomyosarcoma

About: Mediastinal Rhabdomyosarcoma is a research topic. Over the lifetime, 5 publications have been published within this topic receiving 26 citations.

Cardiac tamponade due to malignant pericardial effusion in breast cancer: a case report.

Abstract: Cardiac tamponade resulting from malignant pericardial effusion is an uncommon initial presentation of various extracardiac malignancies. Only twenty-nine cases of extracellular malignancies with this initial presentation have been previously published. Lung carcinoma leads as the most common malignancy involved, followed by carcinoma of the stomach, pancreas, kidney and ovary, mediastinal rhabdomyosarcoma, malignant lymphoma and leukemia. This report describes a case of breast carcinoma in a 47-year-old woman who initially presented with cardiac tamponade. To the best of the authors' knowledge, no similar case has even been reported in the literature.

Common malignancies with uncommon sites of presentation: case 1. Anterior mediastinal rhabdomyosarcoma.

Abstract: A 21-year-old white female presented with a 9-month history of progressively worsening vague chest pressure and discomfort, dyspnea, anorexia, and a 20-lb weight loss. Her medical history was unremarkable, and physical examination was normal, aside from a tachycardia of 120 beats per minute. Computed tomography (CT) of the chest revealed a large, somewhat lobulated, homogeneous anterior mediastinal mass measuring approximately 13 10 8 cm (Fig 1). Despite its size, the mass seemed resectable, without definite invasion of adjacent structures. CT-directed fine-needle aspiration biopsy was performed, and histopathologic examination of the biopsy specimen showed a neoplasm with prominent myxoid differentiation without evidence of lymphoma or thymoma. Given this tentative diagnosis of a soft tissue sarcoma, the resectable appearance of the mass on CT, and a negative metastatic work-up, surgical resection via median sternotomy was undertaken. At the time of operation, the mass appeared larger than reported by the preoperative CT scan and was found to be densely adherent to the pericardium, the mediastinal pleura, and the left lung. Complete surgical resection with negative margins was achieved by wide en bloc resection of these structures along with the tumor (Fig 2). The patient’s recovery was uneventful. Final pathologic examination revealed a high-grade malignant neoplasm with clear-cut features of skeletal muscle differentiation. An area of focal residual thymus was evident (Fig 3, upper left corner) along with the high-grade malignant neoplasm with large atypical cells (Fig 3, lower portion of slide). High-power magnification revealed large tumor cells with prominent round to oval nuclei and intensely eosinophilic cytoplasm—so-called myoblast strap cells. Cross striations in the myoblasts are not seen in this view, however (Fig 4). The tumor was immunoreactive for common muscle actin and desmin, was negative for smooth muscle actin and keratin (CAM 5.2 and AE1/AE3), but demonstrated convincing nuclear positivity for myogen. Final diagnosis was a primary anterior mediastinal rhabdomyosarcoma, anatomically related to, and likely arising from, the thymus. Primary mediastinal rhabdomyosarcomas unassociated with germ cell, teratomatous, or malignant epithelial components are extremely rare. They are thought to arise from the thymus; the ability of thymic tissue to differentiate toward myoid tissue has been reported previously. These tumors tend to occur in the anterior mediastinum of young adults and demonstrate large size and local invasion at the time of diagnosis. Their biologic behavior is aggressive, usually characterized by rapid recurrence and dissemination, even following resection. Because of the limited information regarding treatment of these unusual tumors, therapy must be extrapolated from the management of pediatric rhabdomyosarcomas and applied to these patients. This patient is currently receiving combination chemotherapy

A case of CD20 positive mediastinal rhabdomyosarcoma

Abstract: We present the case of a 16-year-old boy admitted with a large mediastinal mass. Both in the mediastinal tru-cut biopsy and the bone marrow biopsy, a malignant small round cell tumor was determined. The clinical diagnosis was leukemia or lymphoma. The cytoplasmic CD20 expression was shown on the tumor cells of the mediastinal tru-cut biopsy. Rhabdomyosarcoma was diagnosed by the flow cytometric analysis and immunohistochemical demonstration of muscle markers. Rhabdomyosarcomas are traditionally distinguished from lymphomas by their absence of lymphoid markers such as CD20. But in this case we have encountered CD20 expression in the tumor cells. This finding lead us to conclude that the presence of a lymphoid phenotype does not absolutely exclude the diagnosis of rhabdomyosarcoma.