Resected thymic large cell neuroendocrine carcinoma: report of a case

MRI Findings and Differential Diagnosis of Anterior Mediastinal Solid Tumors

The anterior mediastinum is the most common location of mediastinal tumors, and thymic epithelial tumors are the most common mediastinal tumors. It is important to differentiate thymic epithelial tumors from malignant lymphomas and malignant germ cell tumors because of the different treatment strategies. Dynamic contrast-enhanced MRI and diffusion-weighted imaging can provide additional information on the differential diagnosis. Chemical shift imaging can detect tiny fat tissues in the lesion and is useful in differentiating thymic hyperplasia from other solid tumors such as thymomas. MRI findings reflect histopathological features of mediastinal tumors, and a comprehensive evaluation of MRI sequences is important for estimation of the histopathological features of the tumor. In this manuscript, we describe the MRI findings of anterior mediastinal solid tumors and the role of MRI in the differential diagnosis.

Resected thymic large cell neuroendocrine carcinoma: A case report and review of the literature

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Large cell neuroendocrine carcinoma (LCNEC) of the thymus is an extremely rare neoplasm and has a poor prognosis.

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We report a surgical case of thymic LCNEC.

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Further accumulation of knowledge and experience is needed to elucidate the optimal therapy for thymic LCNEC.

Introduction

Large cell neuroendocrine carcinoma (LCNEC) of the thymus is an extremely rare neoplasm.

Presentation of case

We report a rare case of LCNEC of the thymus in a 55-year-old woman. Her chest roentgenogram during a routine checkup revealed an abnormal shadow in the mediastinal left upper lung field. Chest computed tomography showed an anterior mediastinal mass measuring 4.8 × 4.0 cm. Positron emission tomography with 18F-fluorodeoxyglucose (FDG) showed high FDG accumulation at the lesion. To obtain a definitive diagnosis and achieve complete resection, a surgery was performed. The postoperative diagnosis was thymic LCNEC; it was classified as a Masaoka stage III tumor due to the invasion of tumor cells into the left lung. Postoperatively, the patient received adjuvant chemotherapy and survived without any signs of recurrence for 30 months after surgery.

Discussion/conclusion

The detailed clinical features of thymic LCNEC remain unknown because of its rarity. In total, 20 cases of resection for LCNEC, including the present case, have been reported in the English language literature; we have presented a review of these cases and discussed the optimal therapy for this rare and virulent tumor of the thymus.