title: Retinal capillary hemangioma: a comparison of sporadic cases and cases associated with von Hippel-Lindau disease.
abstract: OBJECTIVE
  To report observations regarding the onset of tumors in patients with retinal capillary hemangiomas (RCH) and comparing sporadic cases with those associated with von Hippel-Lindau (VHL) disease.
  
  
  METHODS
  Retrospective consecutive case series.
  
  
  METHODS
  Sixty-eight patients with RCH managed at a tertiary referral center.
  
  
  METHODS
  The data were analyzed for age at diagnosis of RCH, two-hit mutation model, onset of new tumors, and random (Poisson) distribution.
  
  
  RESULTS
  Among 68 patients, we identified 174 RCHs in 86 eyes. Thirty-one patients had VHL disease, and 37 patients were sporadic. The median age at diagnosis in cases with VHL disease was 17.6 years (range, 2.8-46.7 years), and in those without VHL disease it was 36.1 years (range, 7.0-74 years). The age distribution of RCH followed a two-hit mutation model. In eyes with VHL disease, the total number of RCH were distributed randomly as calculated by the Poisson distribution (mean number of tumors = 4). Overall onset of 33 new tumors was documented in 11 eyes (13%) over a median interval of 16 months (range, 3-235 months). All new tumors developed before the age of 47 years. The retinal location of new tumors was similar to the previous tumors with most new tumors located in the superotemporal quadrant (42%) and in the midperipheral retina (58%). Of the 50 patients initially manifesting solitary RCH, only 4 had new tumors develop over a median follow-up duration of 6.4 years (range, 0-33 years). All four cases had VHL disease.
  
  
  CONCLUSIONS
  The median age at diagnosis of RCH in patients with VHL disease was almost 18 years less than those without VHL disease. The age distribution of RCH followed the two-hit mutation model. In VHL disease, the number of RCH is determined randomly. Most of the new RCH develop by the age of 47 years. In the absence of VHL disease, it is unlikely for patients with solitary RCH to develop new tumors.
authors.affiliation: Oncology Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
authors.forename: A D
authors.initials: AD
authors.lastname: Singh
authors.forename: M
authors.initials: M
authors.lastname: Nouri
authors.forename: C L
authors.initials: CL
authors.lastname: Shields
authors.forename: J A
authors.initials: JA
authors.lastname: Shields
authors.forename: A F
authors.initials: AF
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D017668:Age of Onset; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018324:Hemangioma, Capillary / Q000150:complications* / Q000453:epidemiology / Q000473:pathology; D006801:Humans; D008875:Middle Aged; D019572:Retinal Neoplasms / Q000150:complications* / Q000453:epidemiology / Q000473:pathology; D012189:Retrospective Studies; D006623:von Hippel-Lindau Disease / Q000150:complications* / Q000453:epidemiology / Q000473:pathology