title: Treatment when prognostic factors do not match St. Gallen recommendations: profiling of prognostic factors among HR(+) and HER2(-) breast cancer patients.
abstract: BACKGROUND
  The St. Gallen consensus provides treatment recommendations for breast cancer based on prognostic factors. Although many patients' prognostic patterns are not easily matched with the prognostic patterns listed in the St. Gallen consensus, there has been no systematic investigation reporting the gap between treatment recommendations and actual postoperative treatment choices in clinical practice.
  
  
  METHODS
  Four hundred seventy-one patients with hormone receptor-positive [HR(+)] and human epidermal growth factor receptor type 2-negative [HER2(-)] breast cancer were analyzed. These patients were classified into either the "crisp treatment group" or "fuzzy treatment group" based on the definitiveness of postoperative treatment selection based on St. Gallen treatment recommendations. The patients in the fuzzy treatment group were further classified into strata in which patients within each stratum shared the same prognostic factor patterns with similar recurrence rates.
  
  
  RESULTS
  A total of 87.3% of HR(+)HER2(-) patients were designated to the fuzzy treatment group. Four prognostic strata were constructed according to the survival tree model, and revealed that patients with poor prognostic profiles tended to receive endocrine therapy with chemotherapy. This suggests that postoperative chemotherapy is useful, although there was no statistical significance.
  
  
  CONCLUSIONS
  We constructed prognostic profiles of patients in the fuzzy treatment group and examined the recurrence rates associated with two treatment regimens within each prognostic profile. These findings are exploratory, but they may be useful for planning prospective studies of the effectiveness of postoperative treatment regimens among patients with a heterogeneous combination of prognostic factors.
authors.affiliation: Graduate School of Medicine, Kurume University, 67 Asahi-machi, Kurume City, Fukuoka, 830-0011, Japan, a206gm012s@std.kurume-u.ac.jp.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Satoh
authors.forename: Maki
authors.initials: M
authors.lastname: Tanaka
authors.forename: Ayako
authors.initials: A
authors.lastname: Yano
authors.forename: Jiang
authors.initials: J
authors.lastname: Ying
authors.forename: Tatsuyuki
authors.initials: T
authors.lastname: Kakuma
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D017024:Chemotherapy, Adjuvant / Q000592:standards; D016009:Chi-Square Distribution; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D017143:Fuzzy Logic; D006801:Humans; D007150:Immunohistochemistry; D008408:Mastectomy / Q000379:methods / Q000592:standards; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000473:pathology; D009367:Neoplasm Staging; D017410:Practice Guidelines as Topic / Q000592:standards*; D011379:Prognosis; D016016:Proportional Hazards Models; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D018000:Receptors, Peptide / Q000378:metabolism; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D018000:Receptors, Peptide