title: Clinical and pathologic factors of prognostic significance in penile squamous cell carcinoma in a North American population.
abstract: OBJECTIVE
  To analyze, in a clinicopathologic correlation study, a small population of primarily white men with invasive squamous cell carcinoma of the penis for potential prognostic predictors. Penile squamous cell carcinoma is an uncommon cancer in North America. It has a wide spectrum of clinical behavior and an understudied pathogenesis.
  
  
  METHODS
  The data from 43 patients with invasive squamous cell carcinoma of the penis were studied retrospectively. Extensive chart reviews were conducted, glass slides were reviewed, and tissue microarrays were constructed for analysis of immunohistochemical stains p16(INK4a), p53, and Ki-67. Univariate and multivariate logistic regression analyses were performed to elucidate any clinical or pathologic factors that would predict overall survival.
  
  
  RESULTS
  The mean age at diagnosis was 63 years. Most cases (63%) were invasive squamous cell carcinoma, not otherwise specified, and presented as pathologic stage T1 or T2 tumors. Of the 43 patients, 23% died of their disease; 53% of the cases stained for p16(INK4a). Higher pathologic tumor stage and a lack of p16(INK4a) staining were independent predictors of worse overall survival (P = .014) and cancer-specific survival (P = .010).
  
  
  CONCLUSIONS
  Our results have shown that 53% of the invasive penile squamous cell carcinoma cases in this population were associated with human papillomavirus, using p16(INK4a) as a surrogate marker of human papillomavirus infection. These patients had a statistically significant survival advantage, independent of other prognostic factors.
authors.affiliation: Department of Pathology, Capital District Health Authority and Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Gillian
authors.initials: G
authors.lastname: Bethune
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Campbell
authors.forename: Adam
authors.initials: A
authors.lastname: Rocker
authors.forename: David
authors.initials: D
authors.lastname: Bell
authors.forename: Ricardo
authors.initials: R
authors.lastname: Rendon
authors.forename: Jennifer
authors.initials: J
authors.lastname: Merrimen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002170:Canada; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology* / Q000821:virology; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism*; D006801:Humans; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen / Q000378:metabolism; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D030361:Papillomavirus Infections / Q000150:complications / Q000378:metabolism; D010412:Penile Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000821:virology; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53