A pseudosarcomatous dermatofibroma with marked collagen damage is reported. The multinucleated giant cells and proliferation of very elongated sarcomatous-likc fibroblasts histologically resemble a highly mahgnant sarcoma. CASE REPORTA married white female aged 28 presented with a small flat papule in the floor of the left axilla which had been present for 5 years. She complained that it had been occasionally painful and it had slowly increased in size.On examination the lesion was a small, round, firm dermal nodule about i cm in diameter. It was removed under local anaesthesia, and sent for histological examination. HistologyThe epidermis and superfiicial dermis were essentially normal. The cellular proliferation was present in an ill-defined but localized area of the mid-and lower dermis; it did not penetrate into the subcutaneous tissue. There were numerous spindle and stellate cells together with many multinucleated giant cells scattered throughout the affected dermis. Only a few mitotic figures were seen and the nuclei were not grossly pyknotic. The collagen surrounding this cellular proliferation was abnormal in that it appeared hazy and there was coagulation and loss of the usual flbrillar structure seen in fixed and processed preparations. This abnormal dermis at the periphery of the cellular lesion ( Fig. i) was suggestive of a degenerative process which was affecting the collagen. DISCUSSION