A population-level analysis of survival in patients with ALK+ anaplastic large cell lymphoma (ALCL) in the era of novel therapies.

Abstract

e18863 Background: The introduction of novel therapies such as brentuximab vedotin (BV), has changed the treatment paradigm of ALK+ALCL in both upfront and relapsed/refractory settings. We sought to compare differences in the survival trends of patients with ALK+ ALCL in the routine clinical practice, before and after approval of BV (year 2011). Methods: We used SEER-17 registry to identify adult patients using international classification of disease code for oncology assigned to ALK+ ALCL (9714/3) between 2000-2019.We excluded patients (pts) with diagnosis on autopsy or from death certificate, unknown survival time, any other malignancy, cause of death other than non-Hodgkin lymphoma, or survival of < 2 months from diagnosis. Follow-up period was until December 2019. Demographics and treatment details were extracted using SEER Stat v8.4.0.1. Comparisons were made between pts diagnosed in 2000-2010 (pre-BV) vs 2011-2019 (post-BV) using R v4.0. 2. Chi-squared test was used to calculate difference between categorical variables. Kaplan-Meier method and log-rank test were used to estimate overall survival (OS). A multivariate cox proportional hazard (CPH) model, adjusted for sex, radiation, and time-dependent covariates was used to estimate impact of time-period on survival. Results: A total of 1794 pts (n = 956 pre-BV, and 838 post BV) with ALK+ ALCL were identified. The majority were male (1099, 61%), white (78%), and had median age of 49 (IQR: 34-62) years at diagnosis. The baseline characteristics of pts diagnosed during the two time periods were similar (Table). 3-year (y) and 5y OS (95%CI) were 81% (78.1-83.7) and 79% (75.9-81.9) in post-BV vs 61% (58.0-64.2) and 58% (55.5-61.7) during pre-BV period (P < 0.0001, log rank test). Multivariate model showed increased risk of death in the pre-BV vs post-BV period particularly among those surviving > 6 months after diagnosis [log(HR), (95%CI)] = [1.12 (0.86-1.38)]. Conclusions: Using data from nationwide cohort, we demonstrated an improvement in the OS trend of pts with ALK+ ALCL treated in the era of novel targeted therapies, compared to those treated in pre-BV era. [Table: see text]