Post-relapse survival in Waldenstrom macroglobulinemia patients experiencing therapy failure following autologous transplantation.

Waldenström macroglobulinemia (WM) is a rare B-cell lymphoproliferative malignancy. Autologous hematopoietic cell transplantation (auto-HCT) is considered in a subset of WM patients with relapsed disease. While registry data has shown a benefit for auto-HCT in relapsed WM, there is a paucity of data on outcomes of patients relapsing after auto-HCT. Eligibility criteria included adult patients with relapsed/refractory WM who underwent auto-HCT between 2007 and 2017. The primary endpoint was post-relapse overall survival (PR-OS). Secondary endpoints were to identify factors prognostic of PR-OS. Of the 48 patients with WM who underwent auto-HCT, 22 (46%) experienced relapse following auto-HCT. Median PR-OS of relapsed WM patients after auto-HCT (n = 22) was not reached (NR) (95% confidence interval [CI]: 17.5 months-NR). Among patients who relapsed <1 year versus ≥1 year from auto-HCT, the median PR-OS was 18.4 months (95%CI: 0.8-NR) months and NR (95%CI: 17.5-NR), respectively (p = 0.06). Of note, disease status at the time of transplant, CR/VGPR versus partial remission did not appear to impact PR-OS. The median PR-OS was significantly longer in patients who received ibrutinib in the post-transplant setting compared to those who did not (NR vs. 18.4 months, 95%CI: 9.1-NR, p = 0.02). On univariable analysis, the presence of complex karyotype (RR = 4.87, 95% CI = 1.22-19.53) and a higher number of prior lines of therapy (RR = 1.81, 95% CI = 1.23-2.67) were associated with a significantly higher risk of relapse. This is the only study to date that evaluated outcomes of WM patients who relapsed following auto-HCT and provides a benchmark for future trials evaluating survival following auto-HCT relapse.

Survival of Lymphoma Patients Experiencing Relapse or Progression after an Allogeneic Hematopoietic Cell Transplantation.

Outcome and management of patients who relapse after allogeneic hematopoietic cell transplantation (allo-HCT) has evolved in the recent decade. Using a multi-institutional retrospective database we report the predictive factors and survival of lymphoma patients who relapse after allo-HCT. We evaluated 495 allo-HCT recipients transplanted between 2000 and 2015 at 3 academic US medical centers. Landmark analysis evaluating predictive factors was performed at 1 month after allo-HCT relapse with a primary endpoint of postrelapse overall survival (PR-OS). A total of 175 lymphoma patients (35%) experienced relapse after allo-HCT. Of these, 126 patients, median age 46 years (range, 19 to 71), were assessable. Most patients (86%) received subsequent therapy; 80 patients received targeted agents and 19 donor lymphocyte infusion. On univariate analysis median PR-OS for patients with Hodgkin lymphoma was 47.9 months compared with 11.3 months in patients with indolent and 10.1 months in aggressive non-Hodgkin lymphoma (P = .04). On multivariate analysis postrelapse therapy administration (no therapy versus targeted therapy: hazard ratio, .21 [95% confidence interval, .10 to .45]; no therapy versus nontargeted therapy: hazard ratio, .26 [95% confidence interval, .11 to .57]), late relapse 130 days after allo-HCT (relative to early relapse: hazard ratio, .25; P < .001), and Eastern Cooperative Oncology Group performance status of 0 to 1 (versus Eastern Cooperative Oncology Group performance status ≥ 2: hazard ratio, .49; P = .003) were associated with a significantly reduced risk of mortality. Patients relapsing ≥ 130 days from the time of allo-HCT yielded PR-OS of 48.8 months compared with 6.5 months in patients with early relapse (P < .001). Our data suggest that in the modern era, therapies used for patients experiencing lymphoma relapse after allo-HCT can extend survival.