Is neuromyelitis optica with advanced age of onset a paraneoplastic disorder?

Neuromyelitis optica (NMO) antibodies are commonly found in patients with NMO, a relapsing CNS inflammatory disorder. Recent evidence suggests that the NMO antibody may be a paraneoplastic marker. We evaluated this possibility using a health system-wide electronic medical record (EMR), allowing assessment of neoplasm both before and after the assessment of NMO seropositivity.

An automated search of the Cleveland Clinic EMR was performed to identify patients with NMO serology testing (since 2006). Demographic, clinical, and imaging data were collected, including malignancy history.

A total of 41 patients NMO seropositive subjects were found. Average age at first clinical symptom was 38.7 years (SD 15.1), and 33 (80.5%) patients met formal criteria for NMO. Six malignancies were identified in five NMO seropositive patients (12.2%; age 48.7 years [SD 12.4] at presentation of NMO). Cancers included breast carcinoma (three cases), lymphoma, cervical carcinoma and leiomyosarcoma. The timing of malignancy diagnosis varied from 15 years prior to 14 years after the onset of neurologic symptoms. Among seropositive patients over age 50 years at the time of this review, malignancy was seen in 5/25 patients (20%). All five subjects fulfilled NMO clinical criteria.

A high prevalence of malignancy was found in NMO seropositive patients, although the sample size was small. These observations support the possibility of NMO as a paraneoplastic marker. If further studies confirm this relationship, clinicians may consider malignancy screening in individuals seropositive for NMO, particularly those over the age of 48.