Published online Oct 26, 2021. doi: 10.12998/wjcc.v9.i30.9159
Peer-review started: April 1, 2021
First decision: April 28, 2021
Revised: May 19, 2021
Accepted: July 2, 2021
Article in press: July 2, 2021
Published online: October 26, 2021
Processing time: 203 Days and 0.8 Hours
Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disease caused by inherited pathogenic mutations and acquired dysregulations of the immune system. Composite lymphoma is defined as two or more morphologically and immunophenotypically distinct lymphomas that occur in a single patient. Here, we report two cases of HLH secondary to composite lymphoma with mixed lineage features of T- and B-cell marker expression both in the bone marrow and lymph nodes in adult patients.
Two patients were diagnosed with HLH based on the occurrence of fever, pancytopenia, lymphadenopathy, splenomegaly, hemophagocytosis and hyperferritinemia. Immunohistochemical staining of the axillary lymph node and bone marrow in case 1 showed typical features of combined B-cell and T-cell lymphoma. In addition, a lymph node gene study revealed rearrangement of the T-cell receptor chain and the immunoglobulin gene. Morphology and immunohistochemistry studies of a lymph node biopsy in case 2 showed typical features of T cell lymphoma, but immunophenotyping by flow cytometry analysis of bone marrow aspirate showed B cell lymphoma involvement. The patients were treated with high-dose methylprednisolone combined with etoposide to control aggressive HLH progression. The patients also received immunochemotherapy with the R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen immediately after diagnosis. Both patients presented with highly aggressive lymphoma, and died of severe infection or uncontrolled HLH.
We present two rare cases with overwhelming hemophagocytosis along with composite T- and B-cell lymphoma, which posed a diagnostic dilemma. HLH caused by composite lymphoma was characterized by poor clinical outcomes.
Core Tip: Lymphoma-associated hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening clinical disorder. In particular, composite lymphoma with mixed lineage features of T- and B-cell marker expression is extremely rare. We report two cases of HLH secondary to bi-lineage composite lymphoma with lymphocyte infiltrations both in the bone marrow and lymph nodes in adult patients. Case 1 showed typical features of combined B-cell and T-cell lymphoma in axillary lymph node and bone marrow biopsies. Case 2 showed typical features of T cell lymphoma in lymph node biopsy, and B cell lymphoma in bone marrow biopsy. Both patients highlight the diagnostic dilemma, therapeutic challenges and poor prognosis of HLH secondary to composite lymphoma.