Primary large B-cell lymphoma of the adrenal gland has similar clinical, pathological, and genetic features to the primary large B-cell lymphoma of immune-privileged sites

Abstract Primary large B-cell lymphoma of immune-privileged sites (IP-LBCL) is a newly categorized disease entity in the 5th WHO Classification of Tumors. Through the analysis of 47 primary adrenal large B-cell lymphoma (PA-LBCL) cases, we unraveled the similarity to IP-LBCL in clinical presentation, pathological features, and genetic landscape. Our findings reveal a predominant immunophenotype of Bcl6 + CD10-Mum1 + in PA-LBCL, mirroring that observed in IP-LBCL, and a shared mutation spectrum characterized by the notable presence of PIM1, MYD88 L265P and CD79B mutations. Moreover, PA-LBCL emerges as a unique subset within the lymphoma spectrum, exhibiting a more favorable prognosis than DLBCL-NOS with secondary adrenal involvement, a revelation that challenges existing paradigms. The study not only calls for a reevaluation of PA-LBCL’s classification within the realm of large B-cell lymphomas but also opens new avenues for targeted therapeutic strategies and prognostic assessment. This research improves our understanding of lymphomas, particularly those arising in atypical locations, reshaping the landscape of lymphoma classification and management.