title: Expression of p16 and p53 in Intraepithelial Periocular Sebaceous Carcinoma.
abstract: OBJECTIVE
  Identifying intraepithelial sebaceous carcinoma cells in small periocular biopsies can be difficult, particularly in the conjunctiva. The goal of this study was to evaluate p53 and p16 immunohistochemistry as potential markers of intraepithelial sebaceous carcinoma.
  
  
  METHODS
  A total of 25 tumors, including 4 recurrent lesions, were stained for p16 and p53, with intensity scored as negative, weak, moderate or strong.
  
  
  RESULTS
  Expression of p16 was detected in intraepithelial sebaceous carcinoma cells in 24 of the 25 cases (96%), with only 1 case showing weak immunoreactivity. Intraepithelial p53 immunoreactivity was present in 17 of 25 tumors (68%), but was weak in 3 cases. Expression levels remained relatively stable in primary and recurrent tumors, but varied in a few cases between intraepithelial and subepithelial sites.
  
  
  CONCLUSIONS
  Intraepithelial sebaceous carcinomas stained for p53 and p16 demonstrated moderate to strong immunoreactivity in 100% of cases for at least one of these proteins, suggesting that together they are useful markers for determining the extent of tumor spread. Of the two, p16 was immunoreactive in more cases than p53.
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors.forename: W Robert
authors.initials: WR
authors.lastname: Bell
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors.forename: Kamaljeet
authors.initials: K
authors.lastname: Singh
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors.forename: Anand
authors.initials: A
authors.lastname: Rajan Kd
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors.forename: Charles G
authors.initials: CG
authors.lastname: Eberhart
keywords: Intraepithelial spread; Sebaceous carcinoma; p16 immunohistochemistry; p53 immunohistochemistry