Low symptomatic COVID-19 in an elderly patient with follicular lymphoma treated with rituximab-based immunotherapy: A case report.

Background: Follicular lymphoma is an indolent lymphoma that may progress to a highly aggressive form requiring immunochemotherapy. Most regimens utilize rituximab, an anti-CD20 monoclonal antibody, which may affect the clinical course of novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections [coronavirus disease 2019 (COVID-19)]. Here we describe the first case of mild COVID-19 during ongoing oncological treatment without significant deterioration after rituximab administration.