Rare Case of Hodgkin Lymphoma Transformation into Diffuse Large B-Cell Lymphoma with Atypical Spread Epidurally, Intradurally and Intramedullary: A Case Report

BACKGROUND Hodgkin lymphoma (HL) transformation into diffuse large B-cell lymphoma (DLBCL) is uncommon, and scant information has been published on transformed high-grade lymphomas. Therefore, it is important to present and discuss cases of lymphoma transformation to make new information on disease progression, diagnosis, and treatment more readily available. In this paper, we present a case of HL transformation into DLBCL with atypical dissemination. CASE REPORT A 39-year-old woman presented with severe hip pain. A computed tomography (CT) scan was performed, which showed massive pathological retroperitoneal and pelvic lymphadenopathy. The lymph nodes were biopsied and revealed HL. The patient then underwent 7 cycles of ABVD therapy; however, clinical concern was raised for persistent disease due to the poor response to therapy. A vertebral body biopsy was performed to clarify the diagnosis, and histological analysis revealed DLBCL. Therefore, specific chemotherapy with the R-CHOP scheme was begun; the patient received 8 cycles of rituximab and residual lymphoma tissue irradiation. Two months later, magnetic resonance imaging later demonstrated radiological disease progression with multiple widespread metastases in the spinal vertebrae as well as prevertebral, epidural, intradural, and intramedullary metastatic spread. The patient underwent intrathecal chemotherapy and radiation therapy, after which, full metabolic remission was observed on PET/CT. CONCLUSIONS Vigilance should be maintained for patients with poor response to HL treatment owing to the possible transformation into DLBCL. However, even in such cases, full metabolic remission can be achieved with appropriate treatment.