Predicting the Effectiveness of 2 Chemotherapy Regimens Applied to Breast Cancer Patients by Nutritional and Inflammatory Status

BACKGROUND Pretreatment nutritional and inflammatory indices can affect tolerance and response to neoadjuvant chemotherapy (NAC) in locally advanced and early-stage HER2‑positive breast cancer. Markers that predict different outcomes for anthracycline‑containing versus anthracycline‑free regimens could help tailor personalized treatment. This study examined whether pre‑treatment nutritional and inflammatory indices can distinguish response and survival differences between 2 NAC regimens - ddAC‑THP versus TCHP - in HER2‑positive breast cancer. MATERIAL AND METHODS This single‑center retrospective cohort study included 112 women with HER2‑positive invasive breast cancer treated with ddAC‑THP (n=72) or TCHP (n=40). Baseline serum albumin, lymphocyte, neutrophil, monocyte, C‑reactive protein, and cholesterol levels were used to calculate CONUT, mGPS, CAR, NPS, and PNI. Pathological complete response (pCR) rates, treatment metrics, and overall survival (OS) were compared. RESULTS Baseline characteristics and pCR rates (ddAC‑THP: 55.6%; TCHP: 50.0%; P=0.71) were similar. TCHP patients showed better overall survival (97.5% vs 84.7%; P=0.02). CAR had the strongest ability to differentiate between regimens (AUC 0.76; 95% CI 0.67-0.84; P<0.001), while NPS showed inverse prediction (AUC 0.25; P<0.001). CONUT, mGPS, NLR, LMR, and PNI did not have significant predictive power. There was a trend toward better survival with TCHP, but it did not reach statistical significance (log-rank P=0.065). CONCLUSIONS CAR showed modest discriminative ability between treatment groups in this cohort, while other indices had limited utility. The anthracycline-free TCHP regimen was associated with better observed overall survival than ddAC-THP, although time-to-event analysis showed only a borderline difference in survival.