%0 Journal Article
%T Prognostic value and relapse pattern of HER2-low in hormone receptor-positive breast cancer.
%A Wei T
%A Kang Y
%A Wang X
%A Yue J
%A Xu B
%A Yuan P
%J Thorac Cancer
%V 15
%N 7
%D 2024 Mar 25
%M 38272454
%F 3.223
%R 10.1111/1759-7714.15221
%X BACKGROUND: A new concept of HER2-low has emerged in recent years. However, the prognostic value and the relapse pattern of HER2-low is unclear.
METHODS: Our study included patients diagnosed with HER2-negative/hormone receptor-positive breast cancer to explore the differences in survival outcomes between the HER2-low group and the HER2-zero group. More importantly, we explored different recurrence patterns, including the comparison of metastatic sites and recurrence time curve between the two groups.
RESULTS: A total of 797 patients with hormone receptor-positive breast cancer were analyzed. Similar disease-free survival (DFS) was observed between the HER2-low group and HER2-zero group (HR 0.84, 95% CI: 0.61-1.16, p = 0.290). There was also no significant difference in OS between the HER2-low group and the HER2-zero group (HR 0.77, 95% CI: 0.46-1.28, p = 0.310). When IHC 1+ and 0 were taken as a group, the IHC 2+ group had significantly better DFS than the IHC 1+ and 0 group in some subgroups. The risk of bone metastasis in patients with HER2 IHC 1+ and 0 was significantly higher than that of patients with HER2 IHC 2+ (12.7% vs. 4.7%, p < 0.001). Compared with the HER2-zero group, we found that the HER2-low group had a more obvious peak in mortality at the time of postoperative 80th-100th month.
CONCLUSIONS: No significant difference in DFS and OS between the HER2-low group and the HER2-zero group was observed. Patients with HER2 IHC 1+ and 0 tend to develop bone metastasis. The HER2-low group had a more obvious second peak in mortality.