MFH and high-grade undifferentiated pleomorphic sarcoma-what's in a name?

BACKGROUND AND OBJECTIVES

In 2002, with the advent of better classification techniques, the World Health Organization declassified malignant fibrous histiocytoma (MFH) as a distinct histological entity in favor of the reclassified entity high-grade undifferentiated pleomorphic sarcoma (HGUPS). To date, no study has evaluated comparative outcomes between patients designated historically in the MFH group and those classified in the new HGUPS classification. Our goal was to determine the presence of clinical prognostic implications that have evolved with this new nomenclature.

METHODS

Sixty-eight patients were retrospectively evaluated between January 1998 and December 2007. Forty-five patients diagnosed with MFH between 1998 and 2003 were compared to 23 patients in the HGUPS group, from 2004 to 2007. Primary prognostic outcomes assessed included overall survival, metastatic-free, and local recurrence-free survival.

RESULTS

Five-year survivorship between MFH and HGUPS populations, using Kaplan-Meier or competing risk methods, did not show statistical difference for overall survival (60% vs. 74%, P=0.36), 5-year metastasis-free survival (31% vs. 26%, P=0.67), or local recurrence-free survival (13% vs. 16%, P=0.62).

CONCLUSION

Despite new classification nomenclature, there appears to be no identifiable prognostic implications for sarcomas that remain in the unclassifiable HGUPS group, as compared to the previously accepted MFH group.