A case of primary mediastinal Hodgkin lymphoma resected on suspicion of thymic epithelial tumor

Hodgkin lymphoma (HL) with a mediastinal primary tumor are rare and difficult to diagnose. A 53-year-old man presented at our hospital for a routine health checkup. Chest computed tomography (CT) revealed a 37 × 20 × 57 mm mass in the anterior mediastinum. The tumor exhibited a relatively uniform contrast effect, with an unclear border with the pericardium, suggesting the possibility of invasion. Positron emission tomography revealed a considerably high accumulation of ¹⁸ F-fluorodeoxyglucose in the mass. A thymic epithelial tumor was suspected, and surgery was planned without a preoperative tissue biopsy. Thymectomy with partial resection and reconstruction of the right phrenic nerve and pericardium was performed. The final pathological diagnosis was nodular sclerosis HL. This report indicates that when lymphoma is suspected in an anterior mediastinal tumor, a preoperative biopsy should always be considered; however, surgical resection may be a treatment option when the tumor is confined to the mediastinum and is deemed to be completely resectable.