Response rates of extra‐nodal diffuse large B cell lymphoma to anti‐CD19‐CAR T cells: A real word retrospective multicenter study

Abstract

AbstractChimeric antigen receptor T‐cells (CAR‐T) are widely used for the treatment of relapsed/refractory diffuse large B cell lymphoma (DLBCL). The data for CAR‐T cell therapy in patients with extra‐nodal (EN) lymphoma is restricted. We included 126 consecutive patients with DLBCL treated with commercially available CAR‐T cells (tisagenlecleucel, n = 100, 79.4% and axicabtagene ciloleucel, n = 26, 20.6%). At lymphodepletion, 72 of 126 (57%) patients had EN disease, 42 of 126 (33%) patients had nodal disease (ND)‐only and 12 of 126 (10%) showed no disease assessed by PET‐CT. There were no significant differences in CAR‐T related toxicities and in the median Progression free survival (PFS) between EN patients and ND (10.76 [95% CI: 7.8–13.6] vs. 14.1 [95% CI: 10–18.1] months, p = .126). Similarly, median overall survival (OS) was not significantly different (15.36 [95% CI 12.5–18.2] vs. 18.4 [95% CI 14.8–22.1] months, p = .100). Subgroup analysis according to the number of EN involved sites showed that median PFS and OS were significantly higher in patients with <3 EN sites (12.3 months [95% CI 9–15.5] vs. 4.28 months [95% CI 0.6–7.9], p = .010) compared to patients with >2 EN sites, respectively (16.5 months [95% CI 13.4–19.6] vs. 8.7 months [95% CI 4.6–12.8], p = .05). In multivariate cox regression analysis, increased number sites of EN disease and high lactate dehydrogenase (LDH) at lymphodepletion negatively impacted PFS (p = .021 and <.001, respectively), while sex, type of product administered, age and performance status did not predict PFS and OS. Of note, all the patients with involvement of gastrointestinal tract (n = 9), urinary tract (n = 9), or pharynx (n = 3) at lymphodepletion, progressed or had an early relapse. In conclusions, patients with >2 EN sites at lymphodepletion have significantly worse clinical outcomes compared to patients with <3 EN sites. Patients with specific sites of EN disease may demonstrate grim prognosis.