Research on the impact of different chemotherapy and targeted therapy regimens on postoperative disease-free survival in breast cancer patients.

DFS differs markedly among breast cancer subtypes with varied chemotherapy and targeted therapy regimens, making optimal regimen selection critical. To investigate the impact of diverse regimens on DFS across breast cancer molecular subtypes and identify the optimal therapeutic strategies. 106 breast cancer patients were stratified by subtype and treatment regimen and followed up for 3 years. These are preliminary findings from a 3-year follow-up: the overall 3-year DFS rate was 78.30%. In HER2-positive individuals, the 3-year DFS rate of the AC-TH±P regimen (85.71%) was higher than that of the TH regimen (66.67%) with statistical significance (p=0.032), though the sample sizes in the partial HER2-positive subgroups were small and the results need to be verified with larger samples. In hormone receptor-positive individuals, the DFS rate of the AC-taxane regimen (83.33%) was higher than that of the TC regimen (72.73%) (p=0.045), dose-dense regimens outperformed conventional ones (86.84% vs 66.67%, p=0.033) and abemaciclib addition improved DFS in high relapse risk cases (90.91% vs 63.64%, p=0.024). In TNBC, dose-dense regimens showed higher DFS (72.73% vs 53.85%, p=0.040); capecitabine for high relapse risk and olaparib for BRCA1/2 mutations both significantly improved DFS (p<0.05). Multivariate analysis confirmed TNBC, positive lymph node metastasis and non-optimized regimens as independent DFS risk factors (all p<0.05). This preliminary 3-year follow-up study demonstrated that precision individualized treatment is necessary for each subtype of breast cancer: for HER2-positive breast cancer, the AC-TH±P regimen is preferred; for HR-positive breast cancer, a dose-dense AC-taxane regimen is recommended, with abemaciclib added for high recurrence risk; for TNBC, dose-dense chemotherapy, with capecitabine added for high recurrence risk and olaparib added for BRCA1/2 mutations, can significantly prolong DFS.All conclusions are preliminary due to the short 3-year follow-up period and require validation with longer-term follow-up and larger sample sizes.