Head and neck involvement with malignant histiocytosis: case report and literature review.

Malignant Histiocytosis (MH) is a disease being recognized with greater frequency. A case is reported together with a literature review to determine the frequency of this occurrence. Of the 108 case reports of MH reviewed, 43 (39%) had head and neck involvement described, with 22 (20%) having extranodal disease. Nine (40%) of the 22 cases with extra-nodal disease had primary involvement with an apparent survival advantage over the 13 (60%) with secondary involvement (12 mo. vs. 4 mo.). Although those with primary involvement may have apparently localized disease, systemic spread was eventually described in all case reports. Based on the above, MH should be considered as a diagnostic possibility in patients with head and neck lesions, and when diagnosed, systemic therapy should be administered even when the disease is apparently localized.