Presentation
Chest pain
Patient Data
A mass is present in the left chest within the interpleural space, measuring approximately 100 x 130 x 122 mm (width x height x length). It shows heterogeneous density and enhancement suggesting areas of necrosis. The mass displaces the diaphragm and is contiguous with the costal cartilage and ribs. There is a clear separation from the visceral mediastinum. No osteolytic lesions. Feeding arteries arise from both the celiac trunk artery and the internal mammary artery.
Left pleural effusion.
Gross description
The specimens appeared brown, grey and soft, measuring from 1.5 cm to 1.8 cm.
Microscopic description
On a slide prepared from the received specimens and stained with hematoxylin and eosin: Biopsies taken from tumor tissue consist of osteoclast-like multinucleated giant cells located on a background of mononuclear cells. The nuclei of giant cells and mononuclear cells are round or oval, small and even in size, some nuclei are notched, the pigment is smooth, and mitotic nuclei are rare. The interstitium is infiltrated with scattered lymphocytes
Conclusion
Giant cell tumor.
Case Discussion
Our initial diagnosis was solitary fibrous tumor or mesothelioma however a CT-guided core biopsy of the mass revealed a giant cell tumor with benign features.
Primary mediastinal giant cell tumor is a rare tumor that can demonstrate a spectrum of benign to malignant characteristics.