Opsoclonus Myoclonus: Clinical Features, Neoplastic Associations, and Antibody Testing in Adults

Opsoclonus myoclonus (OMS), although uncommon, has distinctive physical characteristics and important diagnostic implications in adults. Autoantibodies can play a role in the disorder's pathogenesis, with Ri/ANNA2 antibodies sometimes seen in patients with OMS and breast cancer. In a retrospective cohort study, investigators characterized clinical information from 114 adult patients with OMS (median age, 45; 54% women; 39% paraneoplastic OMS [P-OMS]; 61% idiopathic OMS [I-OMS]).

P-OMS occurred in association with lung cancer (19 patients), breast cancer (10), ovarian teratoma (8), and other cancers (1 each: testicular seminoma, stomach, thymus, kidney, oropharyngeal carcinoma). Neurologic symptoms preceded tumor diagnoses in 69% of patients.…