(*) Log-rank test. On multivariable regression analysis (MVA) and with imputation for missing data, AHCT was associated with improved PFS (HR, 0.53; 95% CI, 0.43 to 0.66; Silvestrol aglycone .01) and a trend toward improved OS (HR, 0.77; 95% CI, 0.98 to 1 1.01; = .06). to assess for improved overall survival (OS). Cox multivariable regression analysis and propensity scoreCweighted (PSW) analysis were performed. RESULTS Data were collected from 25 medical centers for 1,254 patients; 1,029 met inclusion criteria. Median follow-up for the cohort was 76 months. Median PFS and OS were 62 and 139 months, respectively. On unadjusted analysis, AHCT was associated with improved PFS (75 44 months with without AHCT, respectively; .01) and OS (147 115 months with without AHCT, respectively; .05). On multivariable regression analysis, AHCT was associated with improved PFS (hazard ratio [HR], 0.54; 95% CI, 0.44 to 0.66; .01) and a trend toward improved OS (HR, 0.77; 95% CI, 0.59 to 1 1.01; = .06). After PSW analysis, AHCT remained associated with improved PFS (HR, 0.70; 95% CI, 0.59 to 0.84; .05) but not improved OS (HR, 0.87; 95% Silvestrol aglycone CI, 0.69 to 1 1.1; = .2). CONCLUSION In this large cohort of younger, transplantation-eligible patients with MCL, AHCT consolidation after induction was associated with significantly improved PFS but not OS after PSW analysis. Within the limitations of a retrospective analysis, our findings suggest that in younger, fit patients, AHCT consolidation may improve PFS. INTRODUCTION Mantle cell lymphoma (MCL) is usually a subset of B-cell non-Hodgkin lymphoma characterized by the t(11,14) translocation that leads to overexpression of cyclin D1.1-3 Clinical outcomes of MCL are heterogeneous4-6; high-risk patients have a median survival of only 37 months and 5-year overall survival (OS) of 20%.4,7-9 Efforts to better prognosticate resulted in the MCL International Prognostic Index (MIPI)10, MIPIB, and combined MIPI with Ki-67 index.11-13 First-line treatment options are varied and depend on age, performance status (PS), and comorbidities.14 No approach has shown superiority, although inclusion of cytarabine is associated with improved outcome.15-17 The best outcomes for younger, fit patients were achieved using intensive induction chemoimmunotherapy followed by autologous hematopoietic cell transplantation (AHCT) consolidation15,17; this approach has become the current de facto standard. Examples include R-maxi-CHOP (rituximab plus high-dose cyclophosphamide, doxorubicin, vincristine, and prednisone) with high-dose cytarabine followed by AHCT15 and R-CHOP alternating with R-DHAP (rituximab plus dexamethasone, cisplatin, and cytarabine) followed by AHCT.17 The use of AHCT consolidation is supported by a randomized trial of younger patients with MCL that demonstrated improved progression-free survival (PFS) with AHCT consolidation (39 17 months) over maintenance with interferon alfa.18 However, the lack of rituximab during induction, lack of cytarabine, and use of interferon maintenance make this approach less applicable to todays patients. Furthermore, intensive cytarabine-containing regimens (eg, R-hyperCVAD [rituximab plus hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone]) have shown prolonged disease-free survival without AHCT.19,20 Last, targeted agents in first- or later-line therapy (eg, bortezomib, lenalidomide, and ibrutinib) may negate the need for aggressive induction.21 Therefore, the true benefit of AHCT consolidation in younger, fit patients with MCL in the modern era is not clearly established. Herein we retrospectively assessed the impact of AHCT consolidation on survival in a large cohort of younger patients with MCL treated at multiple North American academic medical centers in the rituximab era. PATIENTS AND METHODS Patients Patients were eligible if age 65 years, newly diagnosed with MCL, and deemed transplantation eligible at diagnosis by the institutional investigator by review of medical records. The diagnosis of MCL was made by a hematopathologist at each Silvestrol aglycone institution as per routine clinical practice. Patients must have received induction from 2000 to 2015 and achieved a partial response (PR) or complete response to induction; responses were defined by the local investigator using institutional standard imaging modalities at time of treatment (ie, computed tomography and/or positron emission tomography). Patients who received radiation therapy alone, achieved less than a PR, were deemed not transplantation eligible because of comorbidities or poor PS, or underwent consolidative allogeneic hematopoietic cell transplantation (allo-HCT) were excluded. AHCT consolidation was defined as transplantation within 6 months of induction. Centers performing transplantation in 0% or Silvestrol aglycone 100% of patients were excluded, as were patients with unknown histology, unknown induction regimen, or missing outcome data. The protocol was approved by the institutional review board of each participating center. Data Collection Data were collected for each patient on baseline characteristics and treatment, transplantation, and outcome (Appendix Table A1, NOS3 online only). MIPI score was calculated for each patient with.