36-year-old female, lens-shaped induration of the skin at the calf with intact epidermis and discrete increased pigmentation. Excision.
- Poorly demarcated cluster in the cutis: plump spindle cells without any typical features arranged in a whirl.
- There may also be foam cells, multinucleated giant cells and haemosiderin deposits
- The epidermis is intact and hyperplastic with hyperpigmentation, and is not affected by the lesion.
This is a common form of fibro-histiocytic neoplasia (refer to specimen S IX
15). It is occasionally difficult to tell apart from related aggressive and malignant tumours..