Allogeneic hematopoietic stem cell transplantation in non‐Hodgkin lymphoma in Switzerland, 30 years of experience: Sooner is better

Due to relatively high nonrelapse mortality (NRM), allogeneic hematopoietic stem cell transplantation (allo‐HSCT) in non‐Hodgkin's lymphoma (NHL) remains the ultimate line of treatment but the only curable approach in a setting of relapse/refractory disease. Here, we conducted a retrospective, multicenter, registry‐based analysis on patients who underwent allo‐HSCT for NHL in Switzerland, over 30‐year (1985–2020) period. The study included 301 allo‐HSCTs performed for NHL patients in three University Hospitals of Switzerland (Zurich, Basel and Geneva) 09/1985 to 05/2020. We assessed in univariate and multivariable analysis the impact on survivals (overall survival [OS], relapse free survival [RFS], relapse incidence [RI], and non‐treatment related mortality [NRM]). The maximum follow‐up was 25 years with median follow‐up for alive patients of 61 months. The median age at allo‐HSCT was 51 years. Three‐ and ‐year OS was ‐ 59.5% and 55.4%; 3‐ and 5‐year PFS was 50% and 44%; 3‐ and 5‐year NRM was 21.7% and 23.6%. RI at 3 and 5 years was 27.4% and 34.9%. In conclusion, our analysis of the entire Swiss experience of allo‐HSCT in patients with NHL shows promising 5‐ and possibly 10‐year OS and relatively acceptable NRM rates for such population, the majority being not in complete remission (CR) at the time of transplantation.