title: Combined expression of p161NK4a and p27Kip1, but not p21WAF1, differentiates endocervical from endometrial adenocarcinoma.
abstract: OBJECTIVE
  To differentiate endocervical adenocarcinoma (ECA) from endometrial adenocarcinoma (EMA) using p16INK4a, p21WAF1 and p27Kip1.
  
  
  METHODS
  The distinction between ECA and EMA can be problematic on small biopsies or in advanced tumor stage. Immunohistochemistry was done on paraffin-embedded tissue sections of hysterectomy specimens of all types of ECA and EMA. Protein expression was scored as 0 to 3 depending on percentage of positive tumor cells.
  
  
  RESULTS
  A total of 40 ECA and 92 EMA cases were examined. For ECA, 32 of 40 (80.0%) cases had score of 3 with p16INK4a expressions; 23 of 92 (25.0%) cases of EMA had similar scores. For p21WAF1 expressions, 28 of 40 (70.0%) ECA cases scored 3 and 72 of 82 (78.2%) of EMA had a similar score. p27Kip1 scored 3 in 17 of 40 (42.5%) ECA cases; only 14 of 92 (15.2%) cases of EMA cases had such a score. We observed significant higher expressions of p16INK4a (p < 0.001) and p27Kip1 (p = 0.001) in ECA than in EMA. Combined positive expression and combined negative expression of p16INK4a and p27Kip1 strongly differentiates ECA from EMA (< 0.0001).
  
  
  CONCLUSIONS
  ECA could be strongly differentiated from EMA based on the expressions of combined p16INK4a and p27Kip1.
authors.affiliation: Department of Pathology, Hospital Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Farveen Marican
authors.initials: FM
authors.lastname: Abu Backer
authors.forename: Nik Raihan Nik
authors.initials: NR
authors.lastname: Mustapha
authors.forename: Nor Hayati
authors.initials: NH
authors.lastname: Othman
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D001706:Biopsy; D018196:Carcinoma, Adenosquamous / Q000378:metabolism / Q000473:pathology; D018269:Carcinoma, Endometrioid / Q000378:metabolism* / Q000473:pathology; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism*; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism*; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism*; D018284:Cystadenocarcinoma, Serous / Q000378:metabolism / Q000473:pathology; D003937:Diagnosis, Differential; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008875:Middle Aged; D002583:Uterine Cervical Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D019941:Cyclin-Dependent Kinase Inhibitor p16; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27