title: Neuroblastoma found in a 4-year-old after rituximab therapy for opsoclonus-myoclonus.
abstract: Opsoclonus-myoclonus, a rare paraneoplastic syndrome that may occur in patients with neuroblastoma, is thought to be a humorally mediated immune reaction to malignant cells that cross-react with autoantigens. This report describes the case of an occult neuroblastoma diagnosed in a 4-year-old female 2 years after presentation of opsoclonus-myoclonus. Although no mass was evident on previous imaging at an interval of 10 months, a computed tomographic scan 4 months after rituximab treatment and 20 months after presentation revealed a new left adrenal mass. Although neuroblastomas can be identified months after presentation of opsoclonus-myoclonus without treatment with rituximab, this report describes one of the longest intervals using up-to-date imaging techniques. Therefore the case raises two concerns: (1) whether the same immune process that causes opsoclonus-myoclonus may suppress neuroblastomas, and (2) whether immunosuppressive therapy with rituximab may inhibit the immune reaction to occult neuroblastomas in patients with unexplained opsoclonus-myoclonus.
authors.affiliation: Department of Pediatrics, Division of Pediatric Hematology/Oncology, Oregon Health & Science University, Portland, 97239-3098, USA.
authors.forename: Bill H
authors.initials: BH
authors.lastname: Chang
authors.forename: Thomas
authors.initials: T
authors.lastname: Koch
authors.forename: Katharine
authors.initials: K
authors.lastname: Hopkins
authors.forename: Suman
authors.initials: S
authors.lastname: Malempati
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000601:surgery; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D009447:Neuroblastoma / Q000175:diagnosis* / Q000276:immunology / Q000601:surgery; D053578:Opsoclonus-Myoclonus Syndrome / Q000188:drug therapy*; D000069283:Rituximab; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D007166:Immunosuppressive Agents; D000069283:Rituximab