title: Immunohistochemical expression of the proliferative marker Ki67 in hydatidiform moles and its diagnostic value in the progression to gestational trophoblastic neoplasia.
abstract: OBJECTIVE
  Considering that Ki-67 is a proliferative marker in molar pregnancies and the possible progression of these kinds of pregnancies to gestational trophoblastic neoplasia (GTN), we decided to evaluate the rate of expression of this marker in patients with uneventful hydatidiform moles and GTN. Moreover, we determined the predictive value of this factor for the progression of molar pregnancies to GTN.
  
  
  METHODS
  In two groups of patients, including 30 patients with uneventful molar pregnancies and 30 patients with GTN, an immunohistochemical staining technique using the Envision method was performed. To evaluate nuclear immunoreactivity of trophoblastic cells for Ki67 on paraffin sections obtained from molar pregnancy products, the percentage of the stained cells was used. Semi-quantitative evaluation was also performed. Data were analyzed using Mann-Whitney tests and receiver operating characteristic curve analysis.
  
  
  RESULTS
  The expression of Ki67 in cytotrophoblastic and syncytiotrophoblastic cells of patients with GTN was significantly more than for patients with an uneventful molar pregnancy (P<0.05). We considered a 12.5% cut-off value for Ki67 in cytotrophoblastic cells and a sensitivity of 90%, specificity 93%, positive predictive value of 93.1% and negative predictive value of 90.3% were obtained. Similarly, considering a cut-off value of 6% for Ki67 in syncytiotrophoblastic cells, results of 90% were obtained for all diagnostic indices.
  
  
  CONCLUSIONS
  Our findings suggest that expression of the Ki67 oncogene in trophoblastic cells in patients with GTN are found far more frequently than in patients with an uneventful molar pregnancy, and demonstrate a high predictive value of progression to GTN.
authors.affiliation: Department of Gynecology Oncology, Women's Health Research Center, Mashhad University of Medical Sciences, Mashhad, Iran. hasanzademofradm@mums.ac.ir
authors.forename: Malihe
authors.initials: M
authors.lastname: Hasanzadeh
authors.forename: Nourieh
authors.initials: N
authors.lastname: Sharifi
authors.forename: Habibollah
authors.initials: H
authors.lastname: Esmaieli
authors.forename: Mahdi Sharife
authors.initials: MS
authors.lastname: Daloee
authors.forename: Azadeh
authors.initials: A
authors.lastname: Tabari
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D031901:Gestational Trophoblastic Disease / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D006828:Hydatidiform Mole / Q000378:metabolism* / Q000473:pathology; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D009367:Neoplasm Staging; D011247:Pregnancy; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D019394:Ki-67 Antigen; D009363:Neoplasm Proteins