- MOPP (mechlorethamine hydrochloride, vincristine, procarbazine hydrochloride, and prednisone): Patients receive MOPP combination chemotherapy comprising mechlorethamine hydrochloride IV on days 1 and 8, vincristine IV on days 1 and 8, oral procarbazine hydrochloride on days 1-14, and oral prednisone on days 1-14. Treatment repeats every 4 weeks for at least 2 courses in the absence of disease progression or unacceptable toxicity.