A case of MOGAD with rectal adenocarcinoma: Comorbidity or paraneoplastic neurological syndrome?

BACKGROUND

Myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune disease characterized primarily by central nervous system demyelination. We report a rare case of MOGAD coexisting with rectal adenocarcinoma.

CASE REPORT: A 59-year-old female presented with fever and bilateral lower limb weakness. MRI of the brain revealed abnormal signals in multiple regions of the cerebrum, brainstem, and spinal cord. Both serum and cerebrospinal fluid tested positive for MOG antibodies. The symptoms improved after steroid therapy. During hospitalization, colonoscopy and pathological examination revealed rectal cancer, which was subsequently treated surgically. After six months of follow-up, neither the tumor nor MOGAD recurred.

CONCLUSION

Paraneoplastic etiologies may also contribute to the development of MOGAD. To date, no cases of MOGAD associated with rectal cancer have been reported. It remains uncertain whether paraneoplastic neurologic syndrome (PNS) is involved in this patient.