Nine months versus 12 months of adjuvant trastuzumab for patients with HER2-positive breast cancer

Purpose This study aimed to compare the results of treatment with adjuvant trastuzumab for 9 months versus 12 months in human epidermal growth factor 2 (HER2)-positive breast cancer patients. The primary endpoint was disease-free survival. Secondary endpoints included cardiac safety, tolerability, and overall survival. Methods The study included 60 non-metastatic HER2-positive breast cancer patients. All study patients underwent surgery, received adjuvant chemotherapy, radiotherapy and hormonal therapy if indicated. Thirty patients were randomized in each group. Group I patients received adjuvant trastuzumab for 12 months, while group II patients received adjuvant trastuzumab for 9 months. Patients were assessed by clinical examination and Echocardiography during treatment. Results After median follow-up of 12 months, 90% of the patients in group I were disease free and 83.3% of patients in group II were disease free (P=0.402). All studied population in both groups I and II were alive at the end of the 1-year follow-up period after the completion of adjuvant trastuzumab treatment thus overall survival is 100%. Conclusion Trastuzumab is tolerable and its side effects are reversible. Nine months of adjuvant trastuzumab treatment is more cost effective than the standard 12 months.