Tumor Characteristics and Survival Rate of HER2-Low Breast Cancer Patients

In this large-scale cross-sectional study, we evaluated disease-free survival (DFS), overall survival (OS), and clinicopathological characteristics of BC patients from 1991 to 2022, retrospectively. We recruited patients referred to the Cancer Research Center in Tehran, Iran, and their HER2 status, which is classified as HER2-low, HER2-positive, or HER2-negative, was obtained from prospectively maintained registries. we aimed to dive more deeply into the clinicopathological characteristics and survival features of HER2-low breast cancer patients and campared it with HER2-negative and HER2-positive groups.Question 1: Is HER2-low breast cancer (BC) a new subtype in the standard classification of BCs? Question 2: How is the DFS and OS rate of HER2-low breast cancer patients in comparison with HER2-negative and HER2-positive groups?

Inclusion Criteria:All breast cancer patients with human epidermal growth factor receptor 2 (HER2) status in the database of the Cancer Research Center (CRC),from April 1991 to March 2022Exclusion Criteria:The male gender Patients with indeterminate or missing HER2 status, or patients with missing DFS and OS information