title: Radiotherapy can improve the disease-free survival rate in triple-negative breast cancer patients with T1-T2 disease and one to three positive lymph nodes after mastectomy.
abstract: OBJECTIVE
  Several studies have demonstrated poor locoregional control in patients with triple-negative breast cancer (TNBC), compared with other molecular subtypes of breast cancer. We sought to evaluate whether or not postmastectomy radiotherapy (PMRT) improves locoregional recurrence-free survival (LRFS) and disease-free survival (DFS) outcomes in TNBC patients.
  
  
  METHODS
  Between January 2000 and July 2007, 553 TNBC patients treated with modified radical mastectomy from a single institution were analyzed retrospectively. Patients were categorized into three groups: low risk (stage T1-T2N0), intermediate risk (stage T1-T2N1), and high risk (stage T3-T4 and/or N2-N3). Cox proportional hazards models were used to evaluate the association between PMRT and LRFS and DFS times after adjusting for other clinicopathologic covariates.
  
  
  RESULTS
  With a median follow-up of 65 months (range, 1-140 months), 51 patients (9.2%) developed locoregional recurrence and 135 patients (24.4%) experienced disease recurrence. On multivariate analysis, PMRT was associated with significantly longer LRFS and DFS times in the entire cohort. In the intermediate-risk group, PMRT was associated with a longer DFS time but not with the LRFS interval. In the high-risk group, PMRT was associated with significantly longer LRFS and DFS times.
  
  
  CONCLUSIONS
  PMRT is associated with longer LRFS and DFS times in high-risk TNBC patients and a longer DFS time in intermediate-risk TNBC patients. Prospective randomized studies are needed to investigate the best locoregional treatment approaches for patients with this molecular subtype of breast cancer.
authors: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, 270 Dong An Rd, Shanghai 200032, China.
authors: Xingxing
authors: X
authors: Chen
authors: Xiaoli
authors: X
authors: Yu
authors: Jiayi
authors: J
authors: Chen
authors: Zhaozhi
authors: Z
authors: Yang
authors: Zhimin
authors: Z
authors: Shao
authors: Zhen
authors: Z
authors: Zhang
authors: Xiaomao
authors: X
authors: Guo
authors: Yan
authors: Y
authors: Feng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery; D008207:Lymphatic Metastasis; D008408:Mastectomy; D008875:Middle Aged; D009367:Neoplasm Staging; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D015996:Survival Rate; D064726:Triple Negative Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*