[Inflammatory leiomyosarcoma: a case report].

We report an additional case of inflammatory leiomyosarcoma, arising in the shoulder of a 31-year-old male. The rare inflammatory variant of leiomyosarcoma tends to affect young adults. Histologically it is characterized by a prominent lymphohistiocytic infiltrate often masking fascicles of spindle cells, as well as the presence of clusters of xanthoma cells and psammoma bodies. Smooth muscle differentiation is supported by desmin and smooth muscle actin expression. The differential diagnosis includes so-called inflammatory 'malignant fibrous histiocytoma'and inflammatory myofibroblastic tumor. The outcome of this variant seems to be favorable.