title: Human Chorionic Gonadotropin (hCG) Regression Curve for Predicting Response to EMA/CO (Etoposide, Methotrexate, Actinomycin D, Cyclophosphamide and Vincristine) Regimen in Gestational Trophoblastic Neoplasia.
abstract: BACKGROUND
  An hCG regression curve has been used to predict the natural history and response to chemotherapy in gestational trophoblastic disease. We constructed hCG regression curves in high-risk gestational trophoblastic neoplasia (GTN) treated with EMA/CO and identified an optimal hCG level to detect EMA/CO resistance in GTN.
  
  
  METHODS
  Eighty-one women with GTN treated with EMA/CO were classified as primary high-risk GTN (n=65) and single agent-resistance GTN (n=16). The hCG levels prior to each course of chemotherapy were plotted in the 10th, 50th, and 90th percentiles to construct the hCG regression curves. Diagnostic performance was evaluated for an optimal cut-off value.
  
  
  RESULTS
  The median hCG levels were 264,482 mIU/mL mIU/mL and 495.5 mIU/mL mIU/mL for primary high-risk GTN and single agent-resistance GTN, respectively. The 50th percentile of the hCG level in primary high-risk GTN and single agent-resistance turned to normal before the 4th and the 2nd course of chemotherapy, respectively. The 90th percentile of the hCG level in primary high-risk GTN and single agent-resistance turned to normal before the 9th and the 2nd course of chemotherapy, respectively. The hCG level of ≥118.6 mIU/mL mIU/mL at the 5thcourse of EMA/CO predicted the EMA/CO resistance in primary high-risk GTN patients with a sensitivity of 85.7% and a specificity of 100%.
  
  
  CONCLUSIONS
  EMA/CO resistance in primary high-risk GTN can be predicted by using an hCG regression curve in combination with the cut-off value of 118.6 mIU/mL at the 5thcourse of chemotherapy.
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand E-mail : r_athithan123@hotmail.com.
authors.forename: Athithan
authors.initials: A
authors.lastname: Rattanaburi
authors.forename: Sathana
authors.initials: S
authors.lastname: Boonyapipat
authors.forename: Yuthasak
authors.initials: Y
authors.lastname: Supasinth
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002648:Child; D006063:Chorionic Gonadotropin / Q000097:blood*; D003520:Cyclophosphamide / Q000627:therapeutic use; D003609:Dactinomycin / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D005047:Etoposide / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D031901:Gestational Trophoblastic Disease / Q000097:blood* / Q000188:drug therapy*; D006801:Humans; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D049451:Nomograms; D011247:Pregnancy; D011379:Prognosis; D012372:ROC Curve; D012044:Regression Analysis; D014750:Vincristine / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D006063:Chorionic Gonadotropin; D003609:Dactinomycin; D014750:Vincristine; D005047:Etoposide; D003520:Cyclophosphamide; D008727:Methotrexate