Atypical involvement of central nervous system in classic Hodgkin lymphoma: a case report

Intracranial Involvement of Systemic Hodgkin Lymphoma: A Case Report and Literature Review

A 27-year-old male patient, previously diagnosed with Hodgkin lymphoma (HL), presented with gait disturbance. Brain MRI showed a 4.5 cm mass lesion in the right occipital lobe, suggesting either intracranial involvement of HL or a potential meningioma. Despite high-dose methotrexate and steroid treatment, the patient's symptoms persisted, and imaging showed an enlarging mass, leading to surgical intervention. Histopathological examination confirmed central nervous system (CNS) involvement of HL. Postoperatively, the patient underwent whole-brain radiotherapy and demonstrated marked clinical improvement. Our literature review from 1980 to 2023 identified only 46 cases of intracranial HL (IC-HL), underscoring its rarity. Lymphomas represent 2.2% of brain tumors, with 90%-95% being diffuse large B-cell lymphoma (DLBCL). In contrast, the incidence of CNS-HL patients is a mere 0.02%. Notably, IC-HL and intracranial DLBCL have differences in their typical locations and treatment strategies. Unlike DLBCL, which predominantly appears in the supratentorial region (87%), IC-HL is found there in 61.5% of cases. Additionally, 33.3% of IC-HL cases occur in the cerebellum, with 43.5% associated with posterior circulation regions. Furthermore, while biopsy followed by chemotherapy induction is a common strategy for DLBCL, 81.8% of IC-HL cases underwent surgical resection, and only 18.1% had a biopsy alone. The distinct characteristics of IC-HL tumors, including their larger size, attachment to the dura, and fibrotic nature with clear boundaries, might account for the preference for surgical intervention. The unique features of IC-HL compared to DLBCL highlight the need for distinct considerations in diagnosis and management.

Rare central nervous system lymphomas

Central nervous system (CNS) lymphomas are rare malignancies characterised by lymphoid infiltration into the brain, spinal cord, cranial nerves, meninges and/or eyes in the presence or absence of previous or concurrent systemic disease. Most CNS lymphomas are of the diffuse large B-cell lymphoma (DLBCL) subtype for which treatment strategies, particularly the use of high-dose methotrexate-based protocols and consolidation with autologous stem cell transplantation, are well established. Other histopathological subtypes of CNS lymphoma are comparatively less common with published data on these rare lymphomas dominated by smaller case series and retrospective reports. Consequently, there exists little clinical consensus on the optimal methods to diagnose and manage these clinically and biologically heterogeneous CNS lymphomas. In this review article, we focus on rarer CNS lymphomas, summarising the available clinical data on incidence, context, diagnostic features, reported management strategies, and clinical outcomes.