Used primarily in the treatment of Hodgkin's lymphoma, often as part of the MOPP regimen (mechlorethamine, vincristine, procarbazine, prednisone). It functions as an alkylating agent and monoamine oxidase inhibitor, interfering with DNA replication and cell division in cancer cells. Also investigated for use in brain tumors due to its ability to cross the blood-brain barrier. Requires careful monitoring due to potential for severe side effects, including myelosuppression and increased risk of secondary malignancies.