[Myxoinflammatory fibroblastic sarcoma: clinicopathologic and immunohistochemical analysis]

To study the specific features of myxoinflammatory fibroblastic sarcoma (MIFS), by providing clinicopathologic and immunohistochemical evaluations of neoplasms and the biological behavior of these tumors and analyzing their recurrent forms.

Ten cases of MIFS were examined with emphasis on its clinicopathological and immunohistochemical features.

In 9 cases, the tumor involved the acral part of the extremities; in one case, it was located in the superficial tissues of the thigh. All neoplasms had a classical histological pattern of MIFS. Four cases developed local recurrences most likely due to the inadequate volume of surgical intervention. Three tumors held its original histological form, but one showed marked histologic progression. Immunohistochemically, all the tumors expressed vimentin. Some cases exhibited a positive reaction with CD68, factor XIIIa, and podoplanin.

Despite altered morphological patterns, the immunoprofile of recurrent MIFS was retained. A tendency for recurrence requires that the resection margins should be meticulously investigated to exclude residual tumor.