Abstract P2-13-07: Efficacy of short-course adjuvant trastuzumab in early stage breast cancer

Abstract

Abstract Background: A total of 12 months adjuvant Trastuzumab is still the optimal choice for patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer. Still, the adjuvant short course 9-week trastuzumab may be considered as a cost-effective and safe option in developing countries such as Syria. Purpose: The primary objective was disease-free survival after short course adjuvant Trastuzumab therapy in early breast cancer at AI-Bairouni university hospital compared with 6 month of adjuvant trastuzumab , the secondary objective was assessing toxicities especially cardiac toxicity. Patients and methods: Women with histologically confirmed HER2 positive BC with either positive or negative hormone receptor of stages IA,IIA,IIB,IIC,IIIA,IIIB and IIIC were eligible for the study . Patients were assigned to 2 groups . The initial systemic treatment was similar in the 2 groups . Thereafter, no further Trastuzumab or chemotherapy was administered in Arm A; 90 patients (loading dose 4 mg/kg; then 2mg/kg weekly to complete 9 weeks of T), whereas in Arm B that included 157 patients single-agent T was administered to complete 6 months (loading dose 8 mg/kg then 6 mg/kg every 3 weeks) . The LVEF was measured pretreatment, and every 3 months afterword . Results: After a median follow up of 24 months DFS was 89.06% and 89.81% in groups A and B respectively (P=0.11).No obvious side effects have been noticed during the follow up period in group A. otherwise congestive heart failure was reported in 2.55% of group B patients . Conclusion: Short course 9 weeks adjuvant Trastuzumab achieved a good 2 years disease-free survival rate (DFS) compared to 6 month of treatment, with acceptable toxicity and good tolerability for treated patients with early-stage invasive breast cancer. Patients are being monitored for a longer follow up period. Citation Format: Saifo M, Nikoula M. Efficacy of short-course adjuvant trastuzumab in early stage breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-13-07.