Slow growing mediastinal anaplastic large cell lymphoma

Abstract

The patient was a 49-year-old woman. An anterior mediastinal tumor showing a slow progression for the last two years was recognized on chest CT during serial observation over eight years for a solitary ground-glass opacity (GGO) in the left upper lobe. The tumor was 33×25×60 mm, located at the ventral part of the ascending aorta, and showed a comparatively uniform enhancing effect. MRI revealed a soft tissue tumor with an intermediate signal on T1WI, low signal on T2WI, and an enhancing effect. She was strongly suspected of having thymoma, and we performed thymectomy with tumor resection through a median sternotomy. The pathological diagnosis was ALK-negative anaplastic large cell lymphoma (ALCL), which has a high-malignancy potential. We report this rare case showing slow progression with no symptoms for two years preoperatively.