Defining ctDNA Metrics in Posttransplant Lymphoproliferative Disorder (PTLD)

This is a multi-center, phase 2, open-label clinical trial to evaluate the efficacy of dose modified R-EPOCH in high-risk, treatment naïve CD20+ posttransplant lymphoproliferative disorder (PTLD) patients. The purpose of this study is to define the benefit of rituximab with etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin (R-EPOCH) in patients who have high-risk B cell PTLD while those with low-risk disease will be spared of chemotherapy and treated with rituximab alone. Concurrently this study also seeks to evaluate the usefulness of circulating tumor DNA (ctDNA), a novel blood test which has been shown to improve a physician's ability to prognosticate and guide treatment decisions in other types of lymphoma. The goal is to demonstrate that ctDNA is a viable and informative tool in treating PTLD with the hope that in the future it may be used to individualize treatment for patients with PTLD in a way that limits treatment toxicity without losing the effectiveness of the treatment plan.