<prompt> WHO prognostic score for a high-risk GTN is671015  <response>: Modified World Health Organization Prognostic Scoring System, as Adapted by FIGO, by which women whose score is 0-6 are Considered Low Risk Requiring Single-Agent Chemotherapy and score of 7 or more, High Risk Requiring Multiagent Combination ChemotherapyScores0123Age40 40---Antecedent pregnancyMoleAboionTerm--Interval months from index pregnancy44-67-13 13Pretreatment serum hCG10001000-1000010,000-100,000100,000Largest tumor size --3-5 cm 5 cm--Site of metastasesLungSpleen, liverGastrointestinalLiver, brainNo. of metastases--1-45-88Previous failed chemotherapy---Single drug 2 DrugsReference: Williams Obstetrics; 25th edition, chapter 20; Gestational trophoblastic diseases 