Abstract

Introduction: According to Globocan in 2020, the percentage of breast cancer was 24.5% in the world and 25.8% in Viet Nam. Regarding breast cancer, having approximately 60 to 70% Estrogen Receptor - positive (ER). Breast cancers with ER - positive have around 65% with Progesterone Receptor - positive (PR). Patients who have breast cancer with ER - positive and hormone therapy usually have a higher overall survival rate than patients with ER - negative. Therefore, hormone therapy has become a standard therapy in hormone receptor-positive breast cancer for a century.

Method: A descriptive retrospective cohort study on 142 breast cancer patients at Oncology center - Hue Central Hospital, from January 2018 to June 2022. Inclusionary criteria consist of non - metastatic stages and primary breast cancer with no previous hormone therapy. Statistics were collected by questionnaire survey, interview, and medical report. Statistical analysis was performed in SPSS 16.0 and Excel 2016.

Results: The mean age of patients was 49 ± 1.14, and initial stages I - II was 71.2%. As for the current molecular classification, the rate of ER (+) was 124/142 (87.3%), PR (+) 115/142 (81%), Her - 2 (+) 37/142 (26.2%) and Ki 67 ≥ 15% 54/121 (44.6%). As regards the effectiveness, DFS was 42.41 ± 0.94 months, OS was 46.71 ± 0.46 months and the 4 - year survival rate was 93.7%. Following this, risk factors that reduced DFS and/or OS consisted of Lympho node - positive, Ki67 index which was higher than 20%, and one hormone receptor - positive. The number of patients who have undergone side effects of hormone therapy was 53.6% but almost side effects graded from 1 to 2 and we have never recorded any death related to adverse events.

Conclusion: The prognostic features of molecular in breast cancer were likely worse than other foreign research that included the low rate of two hormone receptor - positive, the high Ki 67 index, and the high Her - 2 receptor - positive. In addition, the 4 - year survival rate was nearly 94% and the hormone therapy was safe for cancer patients.