Case Number : Case 2142 - 24 August 2018 Posted By: Dr. Richard Carr

Giant cell tumor of soft tissue with superficial ulceration and granulation tissue

A superficially located tumour composed of epithelioid cells and showing necrosis. Epithelioid cells have pleomorphic nuclei with prominent nucleoli and mitoses are a significant feature. The cells show intracytoplasmic lumina some of which contain erythrocytes. I think this is epithelioid angiosarcoma. Alternatively it could be epithelioid hemangioendothelioma.

Giant cell tumor also crossed my mind.  GGT is defined by two population of cells: background of mononuclear cells and the obvious multinucleated giant cells. The nucleus of the mononuclear cells should look exactly the nuclei in the multinucleated cells. In a way, the mononuclear cells are more important tban the multinucleated giant cells beceause the same type of  multinucleated giant cells can represent a bystander in several pathologic process. So it depends on whether there are enough mononuclear cells between the multinucleated giant cells in this lesion to qualify the biopsy as a giant cell tumor . In my eyes, there are not enough but that is in the eyes of the beholder.

Tbere is ossification in the deep aspect and granularion on the superficial aspect. The multinucleated giant cell reaction or tumor is in the middle. Some kind of zonation and ossification / ossificans. Maybe it's traumatized and reactive in nature. As always, clinical history might help in a tough case like this.

Agree with Anh  about some kind of zonation...but the cellular atypia is worrisome. ?Chondro-osseous primary melanoma

I’m worried about giant cell osteosarcoma but considered peripheral giant cell granuloma

I don't pretend to be a world expert but for me it was a good example of a giant cell tumour of soft tissue.

My understanding is that the tumour is made of two populations the background mononuclear cells (pale eosinophilic cytoplasm, minimal pleomorphism, occasional normal mitotic figures) and evenly scattered reactive osteoclast-type giant cells with the typical amphophilic cytoplasm (these type of cells tending to appear in tumours with recurrent haemorrhage and haemosidering deposition including highly pleomorphic malignancies). Xanthoma cells may be seen. I recommended complete excision. They have peripheral metaplastic bone in 50% and can be encased in a shell of bone. On checking looks like I did not do immunos! Looks like local recurrence ~10% and no established reports of metastasis.

PS Apologies for delayed post due to leave and 25th wedding anniversary!

Congrats

10 hours ago, Dr. Richard Carr said:

 

PS Apologies for delayed post due to leave and 25th wedding anniversary!

Congrats

Congrats Richard!