Details

Autor(en) / Beteiligte

• Lopes Cardozo, J.M.N.
• Byng, D.
• Drukker, C.A.
• Schmidt, M.K.
• Binuya, M.A.
• van ’t Veer, L.J.
• Cardoso, F.
• Piccart, M.
• Smorenburg, C.H.
• Poncet, C.
• Rutgers, E.J.T.

Titel

Outcome without any adjuvant systemic treatment in stage I ER+/HER2− breast cancer patients included in the MINDACT trial

Ist Teil von

• Annals of oncology, 2022-03, Vol.33 (3), p.310-320

Ort / Verlag

England: Elsevier Ltd

Erscheinungsjahr

2022

Quelle

MEDLINE

Beschreibungen/Notizen

• Adjuvant systemic treatments (AST) reduce mortality, but have associated short- and long-term toxicities. Careful selection of patients likely to benefit from AST is needed. We evaluated outcome of low-risk breast cancer patients of the EORTC 10041/BIG 3-04 MINDACT trial who received no AST. Patients with estrogen receptor-positive, HER2-negative, lymph node-negative tumors ≤2 cm who received no AST were matched 1 : 1 to patients with similar tumor characteristics treated with adjuvant endocrine therapy (ET), using propensity score matching and exact matching on age, genomic risk (70-gene signature) and grade. In a post hoc analysis, distant metastasis-free interval (DMFI) and overall survival (OS) were assessed by Kaplan–Meier analysis and hazard ratios (HR) by Cox regression. Cumulative incidences of locoregional recurrence (LRR) and contralateral breast cancer (CBC) were assessed with competing risk analyses. At 8 years, DMFI rates were 94.8% [95% confidence interval (CI) 92.7% to 96.9%] in 509 patients receiving no AST, and 97.3% (95% CI 95.8% to 98.8%) in 509 matched patients who received only ET [absolute difference: 2.5%, HR 0.56 (95% CI 0.30-1.03)]. No statistically significant difference was seen in 8-year OS rates, 95.4% (95% CI 93.5% to 97.4%) in patients receiving no AST and 95.6% (95% CI 93.8% to 97.5%) in patients receiving only ET [absolute difference: 0.2%, HR 0.86 (95% CI 0.53-1.41)]. Cumulative incidence rates of LRR and CBC were 4.7% (95% CI 3.0% to 7.0%) and 4.6% (95% CI 2.9% to 6.9%) in patients receiving no AST versus 1.4% (95% CI 0.6% to 2.9%) and 1.5% (95% CI 0.6% to 3.1%) in patients receiving only ET. In patients with stage I low-risk breast cancer, the effect of ET on DMFI was limited, but overall significantly fewer breast cancer events were observed in patients who received ET, after the relatively short follow-up of 8 years. These benefits and side-effects of ET should be discussed with all patients, even those at a very low risk of distant metastasis. •Patients who received no AST had a 2.5% lower 8-year DMFI rate than that observed in matched patients who received ET.•Slightly more locoregional recurrences and contralateral breast cancers were observed in patients who received no AST.•These effects and side-effects of ET should be discussed with patients even at a very low risk of distant metastasis.