First-line ASCT Consolidation Confers Real-world Survival Benefit in Mantle Cell Lymphoma

Consolidative autologous stem cell transplant (ASCT) was associated with a statistically significant lower overall mortality risk and higher overall survival (OS) probability in patients with mantle cell lymphoma (MCL) vs those who did not receive consolidation, according to data from a real-world analysis presented at the 2023 Transplantation and Cellular Therapy Meetings.¹

Investigators identified 745 patients with MCL who met the inclusion criteria for the ASCT cohort (cohort 1) and 5245 patients for the non-ASCT cohort (cohort 2). Following propensity score matching, 607 patients were selected for each cohort.

Findings showed that 105 patients in the ASCT cohort died within the study’s selected 6000-day time window, translating to a mortality risk of 17.298%; 153 patients in the non-ASCT cohort died during that window, equating to a mortality risk of 25.206%. The risk difference between the 2 cohorts was –7.908% (95% CI, –12.489% to –3.327%; Z-score = –3.368; P = .0008). The risk ratio was 0.686 (95% CI, 0.55-0.856) in favor of transplant, and the odds ratio was 0.621 (95% CI, 0.47-0.82).

Moreover, the survival probability at the end of the time window was 64.49% for those who underwent ASCT vs 31.56% for those who did not (x2 = 15.079; P = .0001).

Notably, 10 patients from each cohort were excluded from the mortality results due to an outcome occurring outside the time window.

“[These findings] suggest that ASCT consolidation confers a survival benefit in patients able to tolerate it,” study authors Jonathan Shakesprere, MD, and Salahuddin Safi, MD, both of West Virginia University School of Medicine, Morgantown, West Virginia, wrote in a poster. “Based on our data, we would recommend ASCT consolidation for [patients with] MCL as first-line therapy.”

Historically, MCL has been linked with poor response to standard-of-care chemotherapy. For the frontline treatment of patients with this disease, induction chemoimmunotherapy with or without consolidative ASCT is typically considered.

To better understand the effect of ASCT on real-world outcomes of this patient population, investigators used a multi-institutional longitudinal clinical database tool to evaluate patient characteristics and outcomes in patients who did or did not receive consolidation ASCT. Moreover, investigators aimed to analyze potential prognostic indicators currently used for risk stratification in MCL and to examine survival and mortality data for patients who received these 2 approaches.

The TriNetX web-based research data registry and querying tool was utilized to conduct the retrospective study. Patients in cohort 1 were required to have ICD-10 diagnoses of MCL and stem cell transplant without other ICD-10 leukemia or lymphoma diagnoses. In cohort 2, patients needed to have an ICD-10 diagnosis of MCL at presentation without ICD-10 diagnoses of stem cell transplant or other leukemia or lymphoma.

Investigators gathered and analyzed demographic, laboratory work, and outcomes data. To minimize potential confounding factors, investigators utilized propensity score matching. An index event was defined as time of initial diagnosis, and investigators selected a designated time window of 6000 days.

Analysis of mortality risk was conducted with Cox regression modeling. Kaplan-Meier survival analysis was done using a log-rank test for time-to-event analyses to estimate long-term survival rates.

The mean age of patients in the ASCT cohort was 65.2 years (standard deviation [SD], ± 9.51), compared with 60.5 years (SD, ± 9.75) for those in the non-ASCT cohort. Most patients across both cohorts were male (cohort 1, 74.1%; cohort 2, 75.0%) and White ( 83.9%; 82.4%).

Moreover, mean serum lactate dehydrogenase (LDH) levels in cohort 1 and cohort 2 were 241.3 U/L (SD, ± 129.0) and 306.6 U/L (SD, ± 296.6), respectively. The mean ECOG performance status was 0.294 (SD, ± 0.47) in the ASCT cohort and 0.438 (SD, ± 0.727) in the non-ASCT cohort. The mean white blood cell count was 8.9 103/uL (SD, ± 26.4) in the ASCT cohort and 12.0 103/uL (SD, ± 29.8) in the non-ASCT cohort.

“[Patients with] MCL who had received ASCT were on average younger and had lower serum LDH levels on presentation than those who had not received ASCT,” study authors wrote. “Despite both groups having similar initial ECOG [performance statuses], patients in the ASCT group had a statistically significant lower overall mortality risk as well as higher OS probability than their counterparts.”

Reference

Shakesprere J, Safi S. A real-world analysis of autologous stem cell transplantation utilization in mantle cell lymphoma. Presented at: 2023 Transplantation and Cellular Therapy Meetings; February 15-19, 2023; Orlando, FL. Abstract 502.