Opsoclonus-myoclonus in children associated or not with neuroblastoma

To compare the clinical data at diagnosis, treatment and neurological outcome in 34 children with opsoclonus-myoclonus syndrome (OMS) associated with a detected neuroblastoma or not.

This is a multicentric retrospective study of 34 children presenting with OMS from four pediatric centers diagnosed between 1988 and 2008.

Twenty-two patients had OMS associated with a neuroblastoma. These patients all had neuroblastomas with favourable prognostic features; all underwent surgery, six received chemotherapy. Twelve children had OMS without a detected neuroblastoma. For OMS, the main treatment in all children was corticotherapy (n=33), but immunoglobulins (n=13), cyclophosphamide (n=4) and rituximab (n=4) were also given. In the 27 OMS patients with or without neuroblastoma whose follow up was greater than two years, the neurological outcome was evaluated: 59.3% had neurological sequelae, including motor, praxic and/or language sequelae (n=9), persistent ataxia (n=6) and moderate motor deficit (n=3). No significant difference in neurological outcome was noted between the two patient groups.

Our retrospective study provides further evidence that OMS with or without a detected neuroblastoma is the same disease, whose major challenges are the neurological sequelae. An international collaboration is required to improve the knowledge about OMS, the treatment and the outcome in this rare disorder.