title: Vitreous relapse following primary chemotherapy for retinoblastoma: is adjuvant diode laser a risk factor?
abstract: OBJECTIVE
  To evaluate rates of vitreous relapse among retinoblastoma patients treated with primary chemotherapy and assess diode laser as a potential risk factor for relapse.
  
  
  METHODS
  Retrospective review of all patients treated with primary chemotherapy at a large ocular oncology centre. Eyes that developed vitreous relapse were coded with regard to Reese-Ellsworth Group, laterality, time to relapse, type of relapse (vitreous base or non-vitreous base relapse), treatments used (including adjuvant diode laser), and ocular preservation. Individual tumour foci treated with laser hyperthermia were also coded for laser parameters including power settings, number of treatments, and concomitant administration of systemic chemotherapy (chemothermotherapy).
  
  
  RESULTS
  15 of 106 eyes (14.15%) developed vitreous relapse over a 6 year period. Mean time to relapse was 7.2 months after chemotherapy was completed. Five cases (33%) were of the vitreous base variety. Ocular salvage was attempted in 11 cases using a variety of methods; one patient was lost to follow up. Six of the remaining 10 eyes (60%) were salvaged. Eight of 38 eyes (21%) treated with systemic chemotherapy and laser hyperthermia developed vitreous relapse compared with seven of 68 eyes (10%) treated with primary chemotherapy alone (p<0.005). Laser settings, number of hyperthermia treatments, and the concomitant use of systemic chemotherapy (chemothermotherapy) were not associated with higher rates of vitreous relapse.
  
  
  CONCLUSIONS
  Nearly one in seven eyes with retinoblastoma treated with primary chemotherapy may develop vitreous relapse. The administration of diode laser hyperthermia appears to increase this risk. Despite additional therapy a number of these eyes succumb to enucleation.
authors.affiliation: Ocular Oncology Service, Bart's and The London NHS Trust, London, UK.
authors.forename: D S
authors.initials: DS
authors.lastname: Gombos
authors.forename: P A
authors.initials: PA
authors.lastname: Cauchi
authors.forename: J L
authors.initials: JL
authors.lastname: Hungerford
authors.forename: P
authors.initials: P
authors.lastname: Addison
authors.forename: P G
authors.initials: PG
authors.lastname: Coen
authors.forename: J E
authors.initials: JE
authors.lastname: Kingston
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002675:Child, Preschool; D003131:Combined Modality Therapy; D006801:Humans; D006979:Hyperthermia, Induced / Q000009:adverse effects*; D007223:Infant; D053685:Laser Therapy; D007834:Lasers / Q000009:adverse effects; D009366:Neoplasm Seeding; D019572:Retinal Neoplasms / Q000188:drug therapy / Q000628:therapy*; D012175:Retinoblastoma / Q000188:drug therapy / Q000556:secondary* / Q000628:therapy*; D012189:Retrospective Studies; D012307:Risk Factors; D016879:Salvage Therapy / Q000379:methods; D016019:Survival Analysis; D014822:Vitreous Body / Q000473:pathology