Intensive alternating chemotherapy regimen in small cell carcinoma of the lung

Fifty-five patients with small cell carcinoma of the lung (SCCL) were treated with alternating courses of CAV (cyclophosphamide, doxorubicin, and vincristine) and VHM (etoposide, hexamethylmelamine, and methotrexate) at 21-day intervals. One regimen contained high-dose cyclophosphamide (2400 mg/m2 iv), while the second contained an increased dose of etoposide (250 mg/m2 iv on Days 1-3). Patients achieving a complete response (CR) received a minimum of six cycles of therapy or two cycles beyond the achievement of CR. These patients as well as those with partial response with disease limited to the lung then received radiotherapy to the lung primary (5100 rads in 300-rad fractions) as well as prophylactic cranial radiotherapy (3000 rads in 300-rad fractions). All therapy was subsequently stopped until relapse. There were no deaths during the aplastic periods induced by the intensive chemotherapy. CR was achieved in 57% of the patients and partial response was achieved in 38%. The actuarial median survival for the 27 patients with extensive disease was 13.5 months and for the 28 patients with limited disease was 13 months. Survival at this point appears comparable to less intensive regimens in which maintenance therapy was given. We conclude that prolonged intensive induction chemotherapy in SCCL is well-tolerated. Studies are needed to examine in a randomized trial the role of alternating combinations and maintenance therapy in SCCL.