Overall survival according to molecular subtypes and clinical staging in invasive breast carcinoma patients

Kaplan-Meier analysis in a hospital cohort

Abstract

Introduction: Overall survival analysis according to molecular subtypes and clinical staging is essential for understanding prognosis in breast cancer. Objective: To estimate and compare overall survival of patients with invasive breast carcinoma according to clinical staging and main molecular subtypes in a hospital cohort from Central-West Brazil. Methods: Retrospective cohort study with 97 patients with confirmed invasive breast carcinoma, excluding ductal carcinoma in situ. Kaplan-Meier curves were compared by the log-rank test, stratified by staging (I–II vs. III–IV), triple-negative subtype, hormone receptor status, and HER2. Follow-up was estimated from year of treatment initiation. Results: Mean estimated follow-up was 3.9 years (median: 3.0; range: 1–18 years). Six deaths (6.2%) and 9 recurrences (9.3%) were recorded. Advanced staging was associated with significantly worse survival (log-rank p = 2.22 × 10-¹⁰): death rate 50.0% vs. 1.1%. Triple-negative subtype showed worse survival vs. non-triple-negative (log-rank p = 6.32 × 10-⁴): 26.7% vs. 2.4% deaths. Hormone receptor negativity identified a higher-risk subgroup (log-rank p = 6.27 × 10-⁴): 22.7% vs. 1.3% deaths. HER2 status showed no significant difference (log-rank p = 0.983). Conclusion: Advanced staging, triple-negative subtype, and hormone receptor negativity were associated with worse overall survival. These findings reinforce the importance of molecular stratification and early diagnosis for prognostic individualization in breast oncology.