Recurrent Ossifying Fibromyxoid Tumour of Soft Parts. Immunohistochemical Profile and Ultrastructure

1)Department of Neuropathology,
2)Chair and Department of Pathomorphology, Jagiellonian University Medical College, Krakow

Abstract

Growing bulk of evidence supports a view that ossifying fibromyxoid (OFMT) tumor histogenetically belongs to tumors derived from peripheral nerve sheath. Its precise cellular ancestor is disputable nevertheless the Schwann cell should be considered as a first candidate. Clinical behavior of this rare and usually benign neoplasm can probably vary from benign to even truly malignant, though the latter possibility is extremely rare. We present a case of recurrent OFMT located subcutaneously in the medial aspect of the knee in 66-year-old male. Macroscopically, microscopically, and immunohistochemically both primary and recurrent tumors were almost identical. Tumors were entirely negative for S-100 protein and strongly positive for neuron specific enolase. However, electron microscopy did not reveal any traces of basal lamina. Apparent lack of vascularization of tumor tissue may play an important role in the morphogenesis of OFMT.

Address for correspondence and reprint requests to:
D. Adamek M. D.,
Department of Neuropathology,
Botaniczna 3, 31-503 Krakow.