Classical Hodgkin lymphoma presenting with aortic arch encasement and C7–T1 neural foraminal extension: a rare case report

Background Classical Hodgkin lymphoma (cHL) is a B-cell malignancy that typically presents with painless lymphadenopathy and constitutional symptoms. Extranodal involvement is uncommon, particularly within the nervous system. Simultaneous neural foraminal extension with spinal canal infiltration and great-vessel encasement is exceptionally rare. Case presentation A 44-year-old man presented with fever, dyspnea, neck swelling, fatigue, and right upper limb neuropathic pain suggestive of C7–T1 radiculopathy. Imaging revealed a large anterior mediastinal mass encasing the aortic arch with associated cervical and mediastinal lymphadenopathy. Core biopsy was non-diagnostic due to fibrosis, while excisional lymph node biopsy confirmed classical Hodgkin lymphoma, nodular sclerosis subtype with CD15+, CD30+ immunophenotype. Bone marrow biopsy showed no lymphomatous involvement. HIV testing was negative. FDG PET/CT demonstrated hypermetabolic cervical and mediastinal disease with extension into the C7–T1 neural foramina and spinal canal, along with T1 vertebral body osseous involvement, consistent with Stage IVB disease (IPS score: 2). The patient achieved complete metabolic response following six cycles of ABVD chemotherapy without surgical decompression or radiotherapy. Discussion Neurological manifestations of cHL are rare and usually result from direct extension into adjacent neural structures. This case illustrates the diagnostic challenges associated with atypical presentations, particularly when neurological symptoms coexist with mediastinal disease. It highlights the limitations of core needle biopsy in fibrotic lesions and reinforces the importance of excisional biopsy. Conclusion This case expands the spectrum of recognized presentations of cHL by documenting a rare concurrent presentation of great-vessel encasement, neural foraminal extension, and vertebral osseous involvement as an initial manifestation. The diagnostic challenges posed by fibrotic lesions underscore the critical importance of excisional biopsy for definitive diagnosis. Clinicians should maintain a high index of suspicion for lymphoma in the differential diagnosis of mediastinal masses associated with radiculopathy and recognize that chemotherapy alone achieves excellent outcomes even in cases with apparent neural compromise.