AUTHOR=Liu Hui , Shen Qi , Chang Chung-Che , Hu Shimin 

TITLE=Case Report: Phenotypic Switch in High-Grade B-Cell Lymphoma With MYC and BCL6 Rearrangements: A Potential Mechanism of Therapeutic Resistance in Lymphoma?

JOURNAL=Frontiers in Oncology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2021.795330

DOI=10.3389/fonc.2021.795330

ISSN=2234-943X

ABSTRACT=<p>Lineage switch between myeloid and lymphoid in acute leukemia is well established as a mechanism for leukemic cells to escape chemotherapy. Cross-lineage transformation is also recognized in some solid tumors on targeted therapy, such as adenocarcinomas of the lung and prostate that transforms to neuroendocrine carcinoma on targeted therapy. Now lineage plasticity is increasingly recognized in mature lymphomas, such as small B-cell lymphomas transforming to histiocytic/dendritic cell sarcoma. However, there is no report of aggressive mature B-cell lymphoma switching from one histologic category to another upon targeted therapy. We report here a case of high-grade B-cell lymphoma with <italic>MYC</italic> and <italic>BCL6</italic> rearrangements relapsing as a high-grade plasmablastic neoplasm with <italic>MYC</italic> and <italic>BCL6</italic> rearrangements after R-CHOP and R-EPOCH therapy. Being aware of this rare scenario will help improve our understanding of the underlying mechanisms of therapeutic resistance and progression of lymphoma.</p>