title: Identification of candidates for postmastectomy radiotherapy in patients with pT3N0M0 breast cancer.
abstract: BACKGROUND
  There is still controversy concerning the indication of postmastectomy radiotherapy (PMRT) for pT3N0M0 breast cancer. To identify the candidates for PMRT in this subset, we investigated failure patterns, and searched for risk factors for isolated locoregional failure in pT3N0M0 breast cancer after mastectomy without PMRT.
  
  
  METHODS
  Among 1,176 patients who received mastectomy without PMRT for untreated unilateral breast cancer between 1990 and 2002, 64 patients (5%) had pT3N0M0 breast cancer (age 30-81 years; median 52.5 years).
  
  
  RESULTS
  Isolated locoregional failure as the initial failure occurred in three patients. For all 64 patients, the 8-year failure-free survival rate, the isolated locoregional failure-free rate, and the distant failure-free rate were 76, 93, and 82%, respectively. Incidence of isolated locoregional failure as the initial failure was 18% (2/11) for patients 40 years or younger and 2% (1/53) for patients older than 40 years. The 8-year isolated locoregional failure-free rates were 73% for patients 40 years or younger and 98% for patients older than 40 years (p = 0.0135).
  
  
  CONCLUSIONS
  Concerning pT3N0M0 breast cancer, incidence of isolated locoregional failure was comparatively low after mastectomy without PMRT. Routine use of PMRT for all pT3N0M0 patients seemed to be unacceptable. PMRT may be useful for younger patients because of the comparatively high incidence of isolated locoregional failure. Because of the small number of cases in our series, further studies are necessary to determine the usefulness of PMRT for younger patients with pT3N0M0 breast cancer.
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: Shigemitsu
authors.initials: S
authors.lastname: Takashima
authors.forename: Shuichi
authors.initials: S
authors.lastname: Shinohara
authors.forename: Naomi
authors.initials: N
authors.lastname: Nakajima
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kataoka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008408:Mastectomy / Q000401:mortality*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D009367:Neoplasm Staging; D011183:Postoperative Complications; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012307:Risk Factors; D015996:Survival Rate