Hexamethylmelamine treatment of sarcomas and lymphomas.

An evaluation of the effectiveness of hexamethylmelamine (HMM) in the treatment of tumors of mesenchymal origin was undertaken in 75 patients. To determine the efficacy of HMM for treatment of sarcomas, records of 61 patients treated with this drug were reviewed. One patient with metastatic osteosarcoma obtained a complete response of greater than 8 years duration. Shorter partial responses were observed in individual patients with a leiomyosarcoma, a fibrosarcoma, and a lymphangiosarcoma. Stabilization of disease process for intervals up to 5 years occurred in 20 patients with sarcomas. The records of 14 Hodgkin and non‐Hodgkin lymphomas treated with HMM were also reviewed. Two of these patients had complete responses while partial responses were noted in 10 others. Although a variety of dosages were used, all responses were at doses of 8 mg/kg and almost all occurred within 30 days of initiation of therapy. Responses were observed in 5 lymphoma patients who had had prior alkylating‐agent therapy. At the doses used (up to 12 mg/kg), only 17% of the patients had white blood counts less than 3,000, and only 4% had platelet counts below 50,000. Moderate to severe gastrointestinal toxicity limited therapy in 48% of patients.