Triple-negative or HER2-positive status predicts higher rates of locoregional recurrence in node-positive breast cancer patients after mastectomy

Purpose To evaluate the prognostic value of determining estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2) expression in node-positive breast cancer patients treated with mastectomy. Methods and Materials The records of 835 node-positive breast cancer patients who had undergone mastectomy between January 2000 and December 2004 were analyzed retrospectively. Of these, 764 patients (91.5%) received chemotherapy; 68 of 398 patients (20.9%) with T1–2N1 disease and 352 of 437 patients (80.5%) with T3–4 or N2–3 disease received postoperative radiotherapy. Patients were classified into four subgroups according to hormone receptor (Rec+ or Rec-) and HER2 expression profiles: Rec-/HER2- (triple negative; n = 141), Rec-/HER2+ ( n = 99), Rec+/HER2+ ( n = 157), and Rec+/HER2- ( n = 438). The endpoints were the duration of locoregional recurrence–free survival, distant metastasis–free survival, disease-free survival, and overall survival. Results Patients with triple-negative, Rec-/HER2+, and Rec+/HER2+ expression profiles had a significantly lower 5-year locoregional recurrence-free survival than those with Rec+/HER2- profiles (86.5% vs. 93.6%, p = 0.002). Compared with those with Rec+/HER2+ and Rec+/HER2- profiles, patients with Rec-/HER2- and Rec-/HER2+ profiles had significantly lower 5-year distant metastasis–free survival (69.1% vs. 78.5%, p = 0.000), lower disease-free survival (66.6% vs. 75.6%, p = 0.000), and lower overall survival (71.4% vs. 84.2%, p = 0.000). Triple-negative or Rec-/HER2+ breast cancers had an increased likelihood of relapse and death within the first 3 years after treatment. Conclusions Triple-negative and HER2-positive profiles are useful markers of prognosis for locoregional recurrence and survival in node-positive breast cancer patients treated with mastectomy.