Navigating the Diagnostic Gray Zone: A Case Series on Mediastinal Gray Zone Lymphomas
Year: 2026
Type: article
Study design: Case Report
Abstract: Gray zone lymphomas (GZLs) are rare mature B-cell neoplasms characterized by overlapping morphologic and immunophenotypic features of classical Hodgkin lymphoma (CHL) and diffuse large B-cell lymphoma, particularly primary mediastinal B-cell lymphoma, posing significant diagnostic and therapeutic challenges. We present a case series of four patients illustrating the clinicopathologic spectrum of GZL, including mediastinal tumors with discordant CHL-like and B-cell phenotypes, a nonmediastinal systemic GZL, and a rare metachronous presentation demonstrating clonal evolution. These cases highlight marked lineage plasticity, frequent morphologic-immunophenotypic discordance, and the limitations of morphology-based diagnosis alone. Comprehensive immunophenotyping was critical for accurate classification and appropriate therapy selection. This case series underscores the importance of an integrated clinicopathologic approach to avoid misclassification and to guide optimal, biology-driven management of GZLs.
Source: Current Medical Issues
Language: English
Subfield: Pathology and Forensic Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7151920400