title: [Survival and clinical features of retinoblastoma].
abstract: BACKGROUND
  Retinoblastoma (RB) is the most frequent intraocular tumor in the pediatric age group, representing 3 % of all childhood neoplasms. In Mexico, the annual incidence varies according to the geographical area studied, ranging from 4-24 cases/million in patients younger than 15 years. Ninety-five percent of cases occur in infants and pre-school children.
  
  
  METHODS
  An observational, retrospective, descriptive, cross-sectional study of all children with RB admitted to the Oncology Department of the Pediatric Hospital of the National Medical Center in a 10-year period was performed.
  
  
  RESULTS
  Fifty-six patients were included. The median age was 24 months. Forty-two children presented unilateral RB. Symptoms at diagnosis were leukokoria, strabismus and reduced visual sharpness. Distribution according to Prats' classification was the following: stage I, 5 patients; stage II, 32; stage III, 14; stage IV, 5. Histological analysis revealed 24 patients with poorly differentiated RB, 16 with well-differentiated RB, 13 with moderately differentiated RB and 7 with undifferentiated RB. In eight patients histological type was not identified. In 12 of the 56 patients cytogenetic and molecular studies were performed. All patients underwent surgery. Patients in the early stages were treated with chemotherapy. A total of 26.7 % of the group presented relapse. The disease-free survival at 10 years was 87.5 %.
  
  
  CONCLUSIONS
  As with other childhood neoplasms, early diagnosis and multidisciplinary management of RB has improved prognosis and survival. The symptoms, treatment and survival reported in this pediatric cohort are similar to those of other published series.
authors.affiliation: Servicio de Oncología Pediátrica. Hospital del Pediatría del Centro Médico Nacional Siglo XXI. Instituto Mexicano del Seguro Social. Mexico. drarias@hotmail.com
authors.forename: F
authors.initials: F
authors.lastname: Cerecedo Díaz
authors.forename: E
authors.initials: E
authors.lastname: López Aguilar
authors.forename: H
authors.initials: H
authors.lastname: Rivera Márquez
authors.forename: J
authors.initials: J
authors.lastname: Arias Gómez
authors.forename: F
authors.initials: F
authors.lastname: Ramírez Santarita
authors.forename: M
authors.initials: M
authors.lastname: Rodríguez Cruz
mesh_terms: D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D019572:Retinal Neoplasms / Q000175:diagnosis* / Q000401:mortality*; D012175:Retinoblastoma / Q000175:diagnosis* / Q000401:mortality*; D012189:Retrospective Studies; D015996:Survival Rate