Primary mediastinal giant cell tumor

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 cartilagescartilage and ribs. There is a clear separation from the visceral mediastinum. No osteolytic lesions. Feeding arteries arise from both the coeliac trunk artery and the internal mammary artery.

Left pleural effusion.

I. Gross description:

The spicemensspecimens appeared brown, grey and soft, measuring from 1.5 cm to 1.8 cm.

II. Microscopic description:

On a slide prepared from the received specimens and stained with haematoxylin 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

III. Conclusion:

Giant cell tumor.

Our initial diagnosis was solitary fibrous tumour or mesothelioma however a CT-guided core biopsy of the mass revealed a giant cell tumour with benign features.

Primary mediastinal giant cell tumour is a rare tumour that can demonstrate a spectrum of benign to malignant characteristics.