Large B-cell lymphoma associated with fluid overload: two new case reports with molecular insights.

The 5th edition of the World Health Organization (WHO) and the International Consensus Classification (ICC 2022) recently recognized a subtype of diffuse large B cell lymphoma (DLBCL), respectively called fluid overload-associated large B-cell lymphoma (FO-LBCL) and human herpes virus 8 (HHV8)/Epstein-Barr (EBV)-negative primary effusion-based lymphoma. However, few reports have provided a molecular profile for this entity. We present two cases, both females, who presented to our hospital with, respectively, massive pleural and pericardial effusion, but with no other significant pathological findings, and for both of whom FO-LBCL was the final diagnosis.

A Skin Plaque Preceding Systemic Relapse of Gamma-Delta Hepatosplenic T-Cell Lymphoma.

Hepatosplenic T-cell lymphoma (HSTL) is an uncommon, aggressive peripheral T-cell lymphoma with a dismal prognosis, usually expressing gamma-delta T-cell receptor on immunohistochemical study. We report the second instance in the literature of a solitary skin nodule heralding recurrence of HSTL. The patient was a 40-year-old man in apparent remission from HSTL, 4 years after chemotherapy and autologous bone marrow transplant.

T-Cell-Rich Recurrence of Primary Cutaneous Follicle Center Lymphoma After Systemic Rituximab: A Diagnostic Pitfall.

We report on a 74-year-old man with a cutaneous B-cell follicle center lymphoma, which was treated upfront with systemic rituximab and suffered several local relapses. The first of the local recurrences, 10 months after completion of treatment, was characterized by a dense T-cell infiltrate that obscured a minor population of B-cell lymphoma cells, suggesting a second primary cutaneous T-cell lymphoma. This represents a previously not reported diagnostic pitfall and underscores the importance of performing sequential biopsies when dealing with lymphoma recurrences in this setting.