Potential Utility of Circulating Tumor DNA Monitoring in Primary Mediastinal B-Cell Lymphoma Treated with R-DA-EPOCH

Background: Primary mediastinal B-cell lymphoma (PMBCL) is a rare subtype of aggressive B-cell lymphoma. Most relapses occur within the first few months resulting in a dismal prognosis; therefore, it's important to identify primary chemorefractory patients at an early stage, to improve their prognosis. Our group have demonstrated that Circulating Tumor DNA (ctDNA) detected by deep sequencing (DeepSeq) constitute a new non-invasive marker for monitoring response in follicular lymphoma (Jimenez-Ubieto A. et al. ASH 2020). CtDNA monitoring in PMBCL might help to better assess therapeutic response, correct false positive PET/CT results due to residual uptake of the mediastinum and define patients who will benefit from radiation therapy (RT). Here we analyzed the potential value of ctDNA monitoring in 11 PMBCL treated with R-DA-EPOCH between 2018-2020 in the Hospital 12 de Octubre.