Changes of HER2 low expression status in primary and recurrent/metastatic breast cancer.
10.3760/cma.j.cn112151-20230216-00141
- Author:
C LIU
1
;
J K HE
1
;
J Y SHANG
1
;
M YUE
1
;
N N ZHANG
2
;
Y P LIU
1
Author Information
1. Department of Pathology, the Fourth Hospital of Hebei Medical University, Tumor Hospital of Hebei Province, Shijiazhuang 050011, China.
2. Department of Pathology, Central Hospital of Handan, Hebei Province, Handan 056000, China.
- Publication Type:Journal Article
- MeSH:
Humans;
Breast Neoplasms/genetics*;
Clinical Relevance;
In Situ Hybridization, Fluorescence;
Female
- From:
Chinese Journal of Pathology
2023;52(9):912-917
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the evolution and clinical significance of HER2 low expression status in HER2 negative patients in primary and recurrent/metastatic breast cancers. Methods: The data and archived sections of 259 breast cancer patients with recurrence/metastasis and HER2-negative primary foci were collected from January 2015 to January 2022 at the Fourth Hospital of Hebei Medical University, and the HER2 status of primary and recurrence/metastasis foci was determined by immunohistochemistry (IHC), among which IHC 2+patients were subject to fluorescence in situ hybridization (FISH). The HER2 status was classified as HER2-0 group; patients with IHC 1+, IHC 2+and no FISH amplification were classified as HER2 low expression group; and patients with IHC 3+, IHC 2+and FISH amplified were classified as HER2-positive group. The changes of HER2 status in patients with HER2 low expression in primary versus recurrent/metastatic breast cancer foci were compared, and their clinicopathologic characteristics and prognosis were analyzed. Results: The overall concordance rate between primary and recurrent/metastatic HER2 status in breast cancer was 60.6% (157/259, κ=0.178). A total of 102 patients (102/259, 39.4%) had inconsistent primary and recurrent/metastatic HER2 status; 37 patients (37/259, 14.3%) had HER2-0 at the primary foci and HER2-low expression at the recurrent/metastatic; and 56 patients (56/259, 21.6%) had HER2-low expression in the primary foci and HER2-0 in the recurrent/metastatic. The recurrent/metastatic foci became low-expressing compared with the recurrent/metastatic foci which remained HER2-0 patients, with longer overall survival time, higher ER and PR positivity, lower Ki-67 positivity index, and lower tumor histological grade; all with statistically significant differences (all P<0.05). In the primary HER2-low group, patients with recurrent/metastatic foci became HER2-0 while those with recurrent/metastatic foci remained low expression; there were no statistically significant differences in clinicopathological features and overall survival time (all P>0.05). Conclusions: Unstable HER2 status in patients with HER2-0 and low expression in primary versus recurrent/metastatic breast cancer foci, and HER2-0 in the primary foci but low HER2 expression status in recurrence/metastasis is associated with favourable prognosis, and testing HER2 status in recurrence/metastasis can provide more treatment options for such patients.