Clinical Spectrum, Diagnostic Work-up, and Outcomes of Neurolymphomatosis in Lymphoid Malignancies: A 10-Patient Case Series.

PURPOSE: Neurolymphomatosis (NL) is a rare infiltration of cranial nerves, nerve roots, plexuses, or peripheral nerves by malignant lymphoid cells. We aimed to describe the clinical spectrum, diagnostic work-up, treatment, and outcomes of NL in a Middle Eastern tertiary cancer center. PATIENTS AND METHODS: We conducted a retrospective single-center case series of patients with clinically and/or radiologically confirmed NL managed at the National Center for Cancer Care and Research, Qatar, from January 2020 to April 2026. Clinical, imaging, cerebrospinal fluid, treatment, response, and survival data were summarized descriptively. RESULTS: Ten patients were identified; median age was 44.5 years, eight were male, eight had B-cell malignancies, and two had T-lymphoblastic leukemia/lymphoma. Three had synchronous NL at initial diagnosis, whereas seven developed NL with relapsed, refractory, or recurrent disease. MRI supported NL in 7/10 patients, cerebrospinal fluid in 4/10, and PET/CT in 3/10; none underwent direct nerve biopsy. Best neurologic response was complete in three patients, partial in four, and absent in three. Four patients were alive at censoring, and six had died of progressive disease. CONCLUSION: In this regional cohort, NL usually occurred with aggressive active disease and showed heterogeneous neurologic presentations. Diagnosis depended on integrating clinical findings with MRI, PET/CT, and cerebrospinal fluid studies. Although overall outcomes were poor, durable disease control was achieved in selected patients. Multicenter studies are needed to refine diagnostic pathways and treatment strategies.