ESMO open, Volume 10, Issue 12, 5 1 2025, Pages 105923 Pathological complete response and survival after neoadjuvant chemotherapy in patients with stage I TNBC: a registry-based study. de Graaf M, Gielen RCAM, Balduzzi S, Siesling S, Linn SC, Kok M
Background
Pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) is a strong prognostic factor in patients with early-stage triple-negative breast cancer (TNBC). One-third of all patients with early-stage TNBC have stage I disease. Chemotherapy is recommended for most patients with stage I TNBC with an increasing use in the neoadjuvant setting supported by recent guidelines. However, little is known on the chemotherapy benefit for stage I TNBC, in particular the likelihood of a pCR and the prognostic value of pCR in this setting.
Patients and methods
Patients with cT1N0M0 TNBC who received standard of care NACT followed by surgery between 2012 and 2022 were identified from the Netherlands Cancer Registry. Baseline factors associated with pCR (ypT0/is, ypN0) and the impact of pCR on overall survival (OS) were evaluated.
Results
A total of 1144 patients treated with anthracycline-taxane-based NACT were identified. Most patients had cT1N0 disease [n = 1077 (94%)] of no special subtype [n = 1034 (90%)]. In total, 656 patients (57.3%) had a pCR. Younger age [odds ratio (OR) 1.78, 95% confidence interval (CI) 1.38-2.30], higher tumor grade [OR 2.11, 95% CI 1.58-2.81] and smaller tumors [OR 2.03, 95% CI 1.15-3.69] were significantly associated with a higher likelihood of pCR, while patients with a lobular carcinoma were less likely to have a pCR (OR 0.17, 95% CI 0.03-0.67). Platinum-based treatment did not significantly improve the pCR rate (P = 0.9). pCR was associated with a better OS [adjusted hazard ratio (aHR) 0.23, 95% CI 0.11-0.45], with a 5-year OS of 97% versus 90% for patients with and without a pCR, respectively. Of 488 patients with residual disease, 280 (57.4%) received adjuvant capecitabine, which was not significantly associated with improved OS [aHR 0.65, 95% CI 0.30-1.44].
Conclusions
Data from this real-world nationwide Dutch registry on neoadjuvant chemotherapy for stage I TNBC, with the majority of patients having cT1cN0 disease of no special subtype, suggests pCR to be associated with a favorable long-term outcome.
