Proceedings of the 25th BCTRIMS Annual Meeting

Introduction - Neuromyelitis Optica Spectrum Disorders (NMOSD) are immune-mediated disorders of the central nervous system, with anti-aquaporin 4 antibodies most often detected in serum. The increasing number of reports associating cancer and NMOSD raises questions about their interconnectedness, especially when considering a cross-reactive mechanism of tumor cells triggering autoimmunity. Objective – This study aims to investigate the prevalence and characteristics of patients with both cancer and NMOSD, to gain insights into those under care at CIEM MS Research Center. Methods – We reviewed medical records of patients at our Center  diagnosed with NMOSD with a history of cancer. Results - In a cohort of 281 patients with NMOSD, eight patients met the established criteria (2.8%). Four (50%) of them tested positive for anti-AQP-4 antibodies, and six (75%) were female. Identified tumors included breast and cervical cancers (25% each), multiple myeloma (12.5%), pheochromocytoma (12.5%), prostate cancer (12.5%) and bladder cancer (12.5%). Patients presented heterogeneous phenotypes, with initial symptoms such as myelitis (62.5%), optic neuritis (50%), area postrema syndrome (50%) and brainstem syndrome (12.5%). Longitudinally extensive transverse myelitis (LETM) was prominent occurring in seven (87.5%) patients, whereas optic neuritis  occurred in six (75%). Conclusion - Our findings are in line with literature, indicating 3-12% association between NMOSD and cancer, predominantly in females. LETM was the most prevalent symptom. In agreement with other published series, breast and genitourinary cancers were frequently reported histological types.