Neurolymphomatosis (NL) represents a rare manifestation of lymphoma involving the peripheral nervous system. Specifically, it infiltrates cranial nerves, roots, or plexuses. Consequently, a 76-year-old male presented with painful brachial plexopathy. Therefore, he developed numbness and progressive muscle weakness. Crucially, this case demonstrates the importance of tumefactive neurolymphomatosis diagnosis through serial imaging. Furthermore, serial MRI and PET scans are essential for tracking disease progression. Additionally, clinical findings may initially appear nonspecific. Moreover, prompt recognition is vital for effective management. Indeed, earlier detection often improves outcomes. Likewise, clinicians must remain vigilant in oncology settings.

Initially, MRI scans showed a thin subparaneurial rim of enhancement. Subsequently, the C8 nerve root enlarged slightly over several months. However, the lesion soon became a homogeneously enhancing tumefactive mass. Moreover, 18F-FDG PET confirmed hypermetabolic activity along the nerve trunk. Therefore, subtle enhancement often precedes overt masses in these patients. Notably, serial monitoring allowed the clinical team to observe this evolution. Eventually, clinicians performed a targeted fascicular biopsy. Specifically, the pathology results confirmed recurrent B-cell lymphoma. As a result, the diagnosis was definitively established. Similarly, the imaging guided the surgical path to a nonfunctioning fascicle. Thus, the clinical team initiated appropriate treatment promptly.

Advances in Tumefactive Neurolymphomatosis Diagnosis

Specifically, the \"encased nerve\" appearance on MRI is highly significant for this condition. Furthermore, MRI identifies circumferential subparaneurial deposition that characterizes the tumefactive spectrum. Additionally, PET-CT scans show intense hypermetabolism even before major structural changes occur. Consequently, these modalities improve diagnostic accuracy significantly. Moreover, a history of lymphoma warrants high suspicion when plexopathy develops. In addition, focal symptoms require immediate investigation. Therefore, serial monitoring is necessary to capture early changes. Notably, this aids in selecting the best site for targeted biopsy. Subsequently, earlier treatment starts, which may preserve nerve function. Finally, this comprehensive approach helps manage neurological decline effectively.

What is tumefactive neurolymphomatosis?

Tumefactive neurolymphomatosis is a specific pattern of lymphoma where tumor cells deposit circumferentially beneath the paraneurium. This creates an encased appearance of the nerve on imaging and is often associated with painful plexopathy or neuropathy.

How does imaging assist in tumefactive neurolymphomatosis diagnosis?

Serial MRI and PET scans are vital for observing the temporal evolution of the disease. Early signs, such as subtle subparaneurial enhancement, often precede the formation of large tumefactive lesions, allowing for earlier biopsy and intervention.

Disclaimer: This content is for informational and educational purposes only. It does not constitute medical advice or a professional relationship. Refer to the latest local and national guidelines for clinical practice.

References

1. Porche K et al. Temporal evolution of tumefactive neurolymphomatosis with serial MRI and positron emission tomography: illustrative case. J Neurosurg Case Lessons. 2026 May 18. doi: undefined. PMID: 42150198.


2. Kaulen LD et al. Clinical Presentation, Management, and Outcome in Neurolymphomatosis: A Systematic Review. Neurology. 2024 Aug 5;103(3):e209698. doi: 10.1212/WNL.0000000000209698.


3. Grisariu S et al. Neurolymphomatosis: an International Primary CNS Lymphoma Study Group (IPCG) report. Blood. 2010;115(24):5005-5011. doi: 10.1182/blood-2009-12-258210.