title: Impact of aggregate of risk factors for isolated locoregional failure in breast cancer patients treated with mastectomy without radiotherapy.
abstract: BACKGROUND
  The impact of aggregate of risk factors on isolated locoregional failure after mastectomy without radiotherapy was assessed.
  
  
  METHODS
  We reviewed 1091 patients who had stage I-III unilateral breast cancer and received mastectomy between 1990 and 2002.
  
  
  RESULTS
  Median follow-up time was 67 (1-175) months. On multivariate analysis, four or more positive axillary lymph nodes (AXLN ≥4), pT4, primary tumor larger than 5 cm (T >5 cm), severe lymphatic invasion (ly2-3), and negative hormone receptor status (HR negative) were the statistically significant risk factors (hazard ratios 5.78, 2.31, 2.47, 2.99, and 3.40, respectively). The 8-year isolated locoregional failure-free rates of patients with single risk factor were 88% for AXLN ≥4, 93% for pT4, 93% for T >5 cm, 98% for ly2-3, and 97% for HR negative. Considering impact on isolated locoregional failure, AXLN ≥4 was termed the major risk factor and other factors were termed minor risk factors. The 8-year isolated locoregional failure-free rates were 98% for patients with only 0-1 minor risk factors (low-risk group), 86% for patients with the major risk factor alone or with only 2-4 minor risk factors (intermediate-risk group), 72% for patients with the major risk factor plus 1-2 minor risk factors (high-risk group), and 28% for patients with the major risk factor plus 3-4 minor risk factors (very high-risk group).
  
  
  CONCLUSIONS
  Aggregate of risk factors increased the risk of isolated locoregional failure significantly. Patients with the major risk factor plus one or more minor risk factors seemed to be candidates for postmastectomy radiotherapy.
authors.affiliation: Department of Radiation Oncology, National Hospital Organization Shikoku Cancer Center, Kou-160, Minamiumemoto-Machi, Matsuyama, Ehime, Japan. yhamamot@shikoku-cc.go.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hamamoto
authors.forename: Shozo
authors.initials: S
authors.lastname: Ohsumi
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Aogi
authors.forename: Shuich
authors.initials: S
authors.lastname: Shinohara
authors.forename: Naomi
authors.initials: N
authors.lastname: Nakajima
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kataoka
authors.forename: Shigemitsu
authors.initials: S
authors.lastname: Takashima
mesh_terms: D000328:Adult; D001365:Axilla; D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008408:Mastectomy / Q000401:mortality*; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000453:epidemiology / Q000401:mortality; D009367:Neoplasm Staging; D011183:Postoperative Complications; D018714:Radiotherapy, Adjuvant; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D012307:Risk Factors; D015996:Survival Rate; D017211:Treatment Failure
chemical_list: D018160:Receptors, Cytoplasmic and Nuclear