L'istiocitoma fibroso maligno. Presentazione di due casi e revisione della letteratura

: The authors report two cases of malignant fibrous histiocytoma localised in the gluteus maximus and re-evaluate some clinical and biological aspects of the neoplasia. Although its histiogenesis is still unsure, the tumour can be classified into various isotopes: the vorticoid-polymorphous variety (70%), and the myxoid, giant cell, angiomatous and inflammatory varieties. It is the most common soft tissue sarcoma in adults and onset is most frequently observed on the trunk and limbs. Biological behaviour shows a marked tendency to local recidivation, with metastatic diffusion occurring mainly late. The choice of therapy consists of more or less radical surgical removal with or without ratio- and immunotherapy. The results of surgery are influenced by the technique used, and the biological and clinical behaviour of the tumour; in view of the numerous case reports of anomalous behaviour, these factors are only indicative. Therapeutic efficacy is on the whole greater in cases of tumours with diameters of less than 5 cm and more superficial localisations compared to the deep muscular fascia.