Prognostic Analysis Of Targeted Therapy On T₁ Stage HER-2 Positive Breast Cancer

Objective: To assess the prognostic value of clinical pathological characteristics and anti-HER2 therapy in patients with T1 stage HER2 positive breast cancer. Methods: 218 patients who were diagnosed with T1 stage HER2 positive breast cancer from June 1st,2009 to December 31 st,2014 in Xinjiang Cancer Hospital were enrolled, we retrospectively collected the clinical pathological characteristics, anti-HER2 therapy and survival information of those patients, then analyzed the prognostic factors of T1 stage HER2 positive breast cancer. Results: Among 218 patients, 15/218(6.9%) patients were T1 a, 43/218(19.7%) patients were T1 b, 160/218(73.4%) patients were T1 c. With a median42 months(4-75 months) follow-up, we found that those patients with larger tumors,higher histological grade and increased Ki-67 expression would more frequently progress with vascular invasion and axillary lymph node metastasis(p<0.05). The 3 year disease free survival rate was 90.4% and 3 year overall survival rate was 99.5%. Kaplan-Meier survival curves indicated that vascular invasion(P=0.020), axillary lymph node metastasis(P=0.011) and anti-HER-2 targeted therapy were significantly associated with 3 year survival rate. Multivariate analysis showed that the risk of recurrence and metastasis was increased 3.433(95%CI 1.247-9.454,P=0.017)times in patients with axillary lymph node metastasis. Axillary lymph node metastasis is an independent risk factor of T1HER-2 positive breast cancer patients.A total of 47 patients(21.6%) completed the standard 1 year anti-HER-2 targeted therapy. Those patients with hormone receptor(receptor HR, hormone)- negative, vascular invasion and axillary lymph node metastasis would benefit more from anti-HER-2 targeted therapy, with 3 year of DFS rate increased by 15.9%, 26.2% and 25.6%, respectively. Conclusions: Axillary lymph node metastasis is an independent risk factor for T1 stage HER-2 positive breast cancer. Anti HER-2targeted therapy can significantly improve 3 year DFS rate and clinical outcomes of those patients with HR negative, vascular invasion or axillary lymph node metastasis.