Efficacy of trastuzumab deruxtecan in treatment of metastatic breast cancer with overexpression or low expression of HER2 and the influencing factors of prognosis
10.3760/cma.j.cn115355-20230922-00119
- VernacularTitle:德曲妥珠单抗治疗HER2过表达和低表达转移性乳腺癌的效果及预后影响因素分析
- Author:
Junmei ZHANG
1
;
Hongjuan DU
;
Jin YANG
;
Ting YANG
;
Xinli WANG
;
Yan XUE
Author Information
1. 西安国际医学中心医院肿瘤科，西安 710100
- Keywords:
Breast neoplasms;
Human epidermal growth factor receptor 2;
Treatment outcome;
Prognosis;
Trastuzumab deruxtecan
- From:
Cancer Research and Clinic
2024;36(3):167-171
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effect of trastuzumab deruxtecan (T-DXd) in the treatment of metastatic breast cancer (MBC) patients with different expression levels of human epidermal growth factor receptor 2 (HER2) and the influencing factors of prognosis.Methods:The retrospective case series analysis and cohort study were conducted. Clinical data of 20 MBC patients with different expression levels of HER2 treated with T-DXd at Xi'an International Medical Center Hospital from August 2021 to August 2023 were retrospectively collected to analyze the efficacy and safety of T-DXd. The Cox proportional hazards model was used for multivariate analysis of prognostic factors.Results:All 20 patients were female, with a median age [ M ( Q1, Q3)] of 49 years old (40 years old, 58 years old). Of the 20 cases, 12 had low expression of HER2 [immunohistochemistry HER2+, or immunohistochemistry ++ and fluorescence in situ hybridization (FISH)-negative], and 8 had overexpression of HER2 (immunohistochemistry HER2+++, or immunohistochemistry ++ and FISH-positive); median number of lines of treatment with T-DXd was 6 lines (3 lines, 7 lines); 14 patients had partial remission, 3 patients had stable disease, and 3 patients had disease progression, with an objective remission rate (ORR) of 70% (14/20) and a disease control rate of 85% (17/20). Eight patients with overexpression of HER2 had objective remission in 6 cases, and 12 patients with low expression of HER2 had objective remission in 8 cases, and the ORR difference between the two groups was not statistically significant ( P = 1.000). The main adverse reactions of the patients were nausea (14 cases), vomiting (12 cases), leukopenia (10 cases), elevated aspartate aminotransferase (10 cases), elevated alanine aminotransferase (9 cases), anemia (8 cases), fatigue (8 cases), alopecia (8 cases), neutropenia (6 cases), and thrombocytopenia (5 cases); ≥ grade 3 adverse reactions were bone marrow suppression and gastrointestinal reactions, all with an incidence of ≤10%. The median follow-up time was 7.1 months (1.9 months, 11.5 months). The median progression-free survival (PFS) time was 6.5 months (95% CI: 3.9-9.1 months), and the median PFS time of patients with overexpression of HER2 was longer than that of patients with low expression of HER2 [7.0 months (95% CI: 6.4- 7.6 months) vs. 4.0 months (95% CI: 1.7-6.3 months)], and the difference in PFS between the two groups was statistically significant ( P = 0.025). Multivariate Cox regression analysis showed that overexpression of HER2 was an independent protective factor for PFS in MBC patients treated with T-DXd ( HR = 0.265, 95% CI: 0.075-0.945, P = 0.041). Conclusions:MBC patients with overexpression or low expression of HER2 have a good therapeutic effect and safety profile when treated with T-DXd. The overexpression of HER2 may predict good PFS in MBC patients treated with T-DXd, and may serve as a biomarker for predicting PFS in such patients, but it may not affect the ORR.
