title: Postmolar gestational trophoblastic neoplasia: beyond the traditional risk factors.
abstract: OBJECTIVE
  To investigate the slope of linear regression of postevacuation serum hCG as an independent risk factor for postmolar gestational trophoblastic neoplasia (GTN).
  
  
  METHODS
  Multicenter retrospective cohort study.
  
  
  METHODS
  Academic referral health care centers.
  
  
  METHODS
  All subjects with confirmed hydatidiform mole and at least four measurements of β-hCG titer.
  
  
  METHODS
  None.
  
  
  METHODS
  Type and magnitude of the relationship between the slope of linear regression of β-hCG as a new risk factor and GTN using Bayesian logistic regression with penalized log-likelihood estimation.
  
  
  RESULTS
  Among the high-risk and low-risk molar pregnancy cases, 11 (18.6%) and 19 cases (13.3%) had GTN, respectively. No significant relationship was found between the components of a high-risk pregnancy and GTN. The β-hCG return slope was higher in the spontaneous cure group. However, the initial level of this hormone in the first measurement was higher in the GTN group compared with in the spontaneous recovery group. The average time for diagnosing GTN in the high-risk molar pregnancy group was 2 weeks less than that of the low-risk molar pregnancy group. In addition to slope of linear regression of β-hCG (odds ratio [OR], 12.74, confidence interval [CI], 5.42-29.2), abortion history (OR, 2.53; 95% CI, 1.27-5.04) and large uterine height for gestational age (OR, 1.26; CI, 1.04-1.54) had the maximum effects on GTN outcome, respectively.
  
  
  CONCLUSIONS
  The slope of linear regression of β-hCG was introduced as an independent risk factor, which could be used for clinical decision making based on records of β-hCG titer and subsequent prevention program.
authors.affiliation: Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mahmood
authors.initials: M
authors.lastname: Bakhtiyari
authors.affiliation: Department of Perinatology, Mahdiyeh Hospital, Tehran, Iran. Electronic address: drmoradi000@yahoo.com.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Mirzamoradi
authors.affiliation: Department of Obstetrics and Gynecology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Parichehr
authors.initials: P
authors.lastname: Kimyaiee
authors.affiliation: Clinical Research Development Center, Emam Khomaini Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Aghaie
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammd Ali
authors.initials: MA
authors.lastname: Mansournia
authors.affiliation: Department of Obstetrics and Gynecology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sepideh
authors.initials: S
authors.lastname: Ashrafi-Vand
authors.affiliation: Department of Obstetrics and Gynecology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Fatemeh Sadat
authors.initials: FS
authors.lastname: Sarfjoo
mesh_terms: D000328:Adult; D001499:Bayes Theorem; D014408:Biomarkers, Tumor / Q000097:blood*; D016009:Chi-Square Distribution; D006063:Chorionic Gonadotropin / Q000097:blood*; D003661:Decision Support Techniques; D055088:Early Detection of Cancer; D005260:Female; D031901:Gestational Trophoblastic Disease / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D006801:Humans; D006828:Hydatidiform Mole / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D007492:Iran; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D016015:Logistic Models; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011247:Pregnancy; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D006063:Chorionic Gonadotropin
keywords: GTN; human chorionic gonadotropin; independent risk factor; penalized logistic regression