Incidence of second primary malignancies in relapsed/refractory B-cell non-Hodgkin's lymphoma patients in England.

Background: Treatments for relapsed/refractory (r/r) B-cell non-Hodgkin's lymphoma (NHL) may be associated with an increased risk of second primary malignancies (SPMs). Currently available SPM incidence benchmarks are unreliable due to small sample sizes.

Methods: The Cancer Analysis System (CAS), a population-level cancer database in England, was used to identify patients with incident B-cell NHL diagnosed during 2013-2018 with evidence of r/r disease.