title: Disaloganglioside GD2 loss following monoclonal antibody therapy is rare in neuroblastoma.
abstract: BACKGROUND
  Gangliosicle GD2 is abundant on human neuroblastoma (NB). Monoclonal antibody 3F8 targeted to GD2 may have imaging and therapeutic potential. Antigen-negative clones can escape immune-mediated attack leading to clinical resistance or recurrence.
  
  
  METHODS
  Among 95 evaluable patients treated intravenously with 3F8 (94 Stage 4, 1 Stage 3), 66 received nonradiolabeled 3F8, 11 received 131-iodine-labeled-3F8 (8-28 mCi/kg) with autologous bone marrow rescue, and 18 received both forms of treatment. Prior to treatment, 90 patients tested positive for GD2 reactivity by bone marrow immunofluorescence (n = 68), tumor immunohistochemistry (n = 20), or diagnostic radioimmunoscintigraphy (n = 2).
  
  
  RESULTS
  Of 62 patients who had refractory or recurrent neuroblastoma following 3F8 treatment, 61 (98%) tested positive for GD2 reactivity by bone marrow immunofluorescence (n = 51) or tumor immunohistochemistry (n = 10). The sole tumor that lost GD2 expression underwent phenotypic transformation into a pheochromocytoma-like tumor.
  
  
  CONCLUSIONS
  The persistence of GD2 expression in refractory or recurrent NB suggests that complete antigen loss is an uncommon event and cannot account for treatment failure.
authors.affiliation: Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
authors.forename: K
authors.initials: K
authors.lastname: Kramer
authors.forename: W L
authors.initials: WL
authors.lastname: Gerald
authors.forename: B H
authors.initials: BH
authors.lastname: Kushner
authors.forename: S M
authors.initials: SM
authors.lastname: Larson
authors.forename: M
authors.initials: M
authors.lastname: Hameed
authors.forename: N K
authors.initials: NK
authors.lastname: Cheung
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000276:immunology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000276:immunology; D016026:Bone Marrow Transplantation; D019070:Cell Lineage; D002675:Child, Preschool; D003131:Combined Modality Therapy; D017809:Fatal Outcome; D005260:Female; D018305:Ganglioneuroblastoma / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000276:immunology / Q000532:radiotherapy / Q000628:therapy; D005732:Gangliosides / Q000032:analysis* / Q000276:immunology; D006801:Humans; D007116:Immunization, Passive; D018796:Immunoconjugates / Q000627:therapeutic use*; D007074:Immunoglobulin G / Q000276:immunology / Q000627:therapeutic use*; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D009362:Neoplasm Metastasis; D009447:Neuroblastoma / Q000276:immunology / Q000473:pathology / Q000532:radiotherapy / Q000628:therapy*; D016719:Radioimmunodetection; D016499:Radioimmunotherapy; D012074:Remission Induction; D012189:Retrospective Studies; D014182:Transplantation, Autologous
chemical_list: C419226:3F8 antibody; D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D005732:Gangliosides; D018796:Immunoconjugates; D007074:Immunoglobulin G; D007457:Iodine Radioisotopes; C019403:ganglioside, GD2