title: How long have I got? Estimating typical, best-case, and worst-case scenarios for patients starting first-line chemotherapy for metastatic breast cancer: a systematic review of recent randomized trials.
abstract: OBJECTIVE
  To estimate scenarios for survival for women with metastatic breast cancer (MBC) who are starting chemotherapy.
  
  
  METHODS
  We sought randomized, first-line chemotherapy trials for MBC published from 1999 to 2009. We recorded median progression-free survival (PFS) and median overall survival (OS) and extracted the following percentiles (represented scenario) from each OS curve: 90th (worst-case), 75th (lower-typical), 25th (upper-typical), and 10th (best-case). We also estimated these scenarios for each OS curve by multiplying its median by four simple multiples: 0.25 (worst-case), 0.5 (lower-typical), 2 (upper-typical), and 3 (best-case). Estimates were deemed accurate if they were within 0.75 to 1.33 times the actual value.
  
  
  RESULTS
  From 36 trials (13,083 women), the mean for median PFS was 7.6 months (interquartile range [IQR], 6.0 to 9.0 months), the mean for median OS was 21.7 months (IQR,18.2 to 24.0 months), and the mean for the ratio of median OS to median PFS was 3.0 (IQR, 2.4 to 3.5). The mean for each OS scenario was worst-case, 6.3 months (IQR, 4.8 to 7.5 months); lower-typical, 11.9 months (IQR, 9.9 to 13.2 months); upper-typical, 36.2 months (IQR, 31.1 to 41.3 months); and best-case, 55.8 months (IQR, 47.5 to 60.2 months). Simple multiples of the median gave accurate estimates of the worst-case scenario in 73% of OS curves, lower-typical in 97%, upper-typical in 95%, and best-case in 96%. OS was longer in trials with higher proportions of estrogen receptor-positive tumors (P = .001) and in trials of trastuzumab-treated human epidermal growth factor receptor 2-positive tumors (P = .001).
  
  
  CONCLUSIONS
  Simple multiples of an OS curve's median can accurately estimate typical (half to double the median), best-case (triple the median), and worst-case (one quarter of the median) scenarios for survival.
authors.affiliation: National Health and Medical Research Council Clinical Trials Centre and Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Belinda E
authors.initials: BE
authors.lastname: Kiely
authors.forename: Yu Yang
authors.initials: YY
authors.lastname: Soon
authors.forename: Martin H N
authors.initials: MH
authors.lastname: Tattersall
authors.forename: Martin R
authors.initials: MR
authors.lastname: Stockler
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality* / Q000556:secondary; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents