Comparison of Survival Outcomes of Patients with Mantle Cell Lymphoma (MCL) Treated with Autologous Stem Cell Transplant (ASCT) and Conventional Chemotherapy

Mantle cell lymphoma is typically considered to be aggressive and incurable. About 15% of these patients have an indolent course. MCL demonstrates the aggressive features of a rapidly progressive neoplasm but with the negative consequences of an indolent lymphoma, namely incurability and frequent relapses. The median overall survival (OS) was reported at 3–4 years when MCL was first described in the 1990's. OS has since increased substantially and this is thought to be secondary to more aggressive initial therapy and improvement in supportive care. In many parts of the world, autologous stem cell transplant (ASCT) is incorporated in the front line therapy for MCL patients with good performance status. However, improvement in survival has not deemed MCL a curable disease. Concern for treatment-related morbidity seen with aggressive therapy in an incurable disease has led some centers to practice a more conservative approach. The purpose of our study was to compare patient characteristics and the overall survival of patients treated aggressively with ASCT versus conservatively with either conventional chemotherapy or no treatment at a single institution.

52 cases of confirmed mantle cell lymphoma diagnosed at Rush University Medical Center between January 2000 and November 2010 were studied. Demographic, clinical and treatment data were collected and reviewed. The Social Security Death Index and hospital records were used to assess survival. Comparative survival analysis was performed based on treatment strategies including the following: no treatment (watch and wait), chemotherapy, ASCT at any time during course of treatment. None of these patients had an allogeneic stem cell transplant.

43 of the 52 cases met all inclusion criteria and had complete diagnostic and treatment data. The no-treatment group consisted of 5 cases with a median age of 59 years. The chemotherapy group included 23 cases with a median age of 68 years. The most common initial therapy was RCHOP in 14 cases, followed by various other regimens (i.e. bortezomib + rituximab, bendamustine + rituximab) in 7 cases and HyperCVAD in 2 cases. The ASCT group included 15 cases with a median age of 61 years. Pre-transplant chemotherapy was RCHOP in 4 cases, HyperCVAD in 5 cases and other regimens in 6 cases. The comparative survival analysis for the three treatment groups was not statistically significant (p=0.496) and the estimated 3 year OS was 100% for the no treatment group, 74% for the chemotherapy group and 85% for the ASCT group. The estimated 5 year OS was 100% for the no treatment group, 66% for the chemotherapy group and 68% for the ASCT group. There were no cases of allogeneic stem cell transplants.

Our review of MCL cases treated at a single institution supports a role for conservative treatment approaches to this disease entity. This can avoid the potential long term morbidity from ASCT in a subgroup of patients while still keeping the modality of therapy as an option for them at relapse. The incidence of indolent MCL requiring no treatment was 12% which is consistent with those seen in other studies. Further research is necessary to guide treatment decisions for MCL patients whose disease characteristics are intermediate between aggressive and indolent.

Gregory:Genentech:.