title: Sudden dispersion of retinoblastoma shortly after initial chemotherapy treatment.
abstract: OBJECTIVE
  To present 3 cases of unilateral retinoblastoma that demonstrated unusual tumor dispersion shortly after initial chemotherapy treatment.
  
  
  METHODS
  Observational case series.
  
  
  METHODS
  Review of medical records of patients in whom intraocular dissemination of retinoblastoma occurred after initial treatment with chemotherapy.
  
  
  RESULTS
  Three patients demonstrated an atypical response with intraocular dissemination of retinoblastoma shortly after 1 cycle of chemotherapy. All cases had unilateral retinoblastoma with no vitreous seeding or subretinal fluid at presentation. In 2 cases (Cases 2 and 3), there were a few distant subretinal seeds. Per the International Classification of Retinoblastoma, 1 tumor was group E (Case 1), and the other 2 tumors were group D1 (Cases 2 and 3). In 2 cases (Cases 1 and 2), chemotherapy included a 2-drug regimen of carboplatin and etoposide; in the third case, a 3-drug regimen of carboplatin, etoposide, and vincristine was used. In each case, the retinoblastoma dispersed with tumor cells in the vitreous shortly after initial chemotherapy treatment, leading to subsequent enucleation of the eye.
  
  
  CONCLUSIONS
  Retinoblastoma can exhibit an unexpected and sudden dispersion of the tumor shortly after chemotherapy is initiated.
authors.affiliation: Division of Ophthalmology, Children's Memorial Hospital, Chicago, Illinois, USA. gilhut1@gmail.com
authors.forename: Reut
authors.initials: R
authors.lastname: Parness-Yossifon
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Bryar
authors.forename: Joanna L
authors.initials: JL
authors.lastname: Weinstein
authors.forename: Divya
authors.initials: D
authors.lastname: Srikumaran
authors.forename: Marilyn B
authors.initials: MB
authors.lastname: Mets
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects*; D016190:Carboplatin / Q000008:administration & dosage / Q000009:adverse effects; D002675:Child, Preschool; D005047:Etoposide / Q000008:administration & dosage / Q000009:adverse effects; D015353:Eye Enucleation; D005134:Eye Neoplasms / Q000556:secondary*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009366:Neoplasm Seeding; D019572:Retinal Neoplasms / Q000188:drug therapy / Q000473:pathology*; D012175:Retinoblastoma / Q000188:drug therapy / Q000556:secondary*; D014750:Vincristine / Q000009:adverse effects; D014822:Vitreous Body
chemical_list: D014750:Vincristine; D005047:Etoposide; D016190:Carboplatin