A Spanish pilot study reports the five-year results of giving hypofractionated chemotherapy and radiotherapy together before surgery in patients with HER2-positive or triple-negative breast cancer. The approach showed good local control and high survival figures, with toxicity considered acceptable.
What was known
Concurrent chemoradiotherapy is an established treatment in several solid tumours, but in breast cancer its role remains investigational. Mature data on its long-term efficacy and safety when given before surgery in high-risk subtypes were lacking.
What this work adds
This is a prospective, single-centre pilot study that included 62 patients with non-metastatic HER2-positive or triple-negative breast cancer treated between 2018 and 2022. They received hypofractionated radiotherapy (40.5 Gy in 15 fractions, with a simultaneous integrated boost to 54 Gy to the visible tumour guided by 18-FDG PET-CT) together with subtype-specific systemic therapy, followed by surgery four to six weeks later. The primary endpoints were pathological complete response, toxicity and long-term oncological outcomes.
Main results
Sixty-two patients were included (median age 53 years): 28 with triple-negative tumours (45%) and 34 HER2-positive (55%). Sixty completed the preoperative treatment. Breast-conserving surgery was achieved in 68% of cases. Pathological complete response (Miller-Payne grade 5) was obtained in 60% overall: 70% in triple-negative and 52% in HER2-positive patients. No grade 3 or higher late toxicity was observed. 43% had G2 cytopenia, 26% G3 and 13.7% G4. 7% of HER2-positive patients had transient, asymptomatic declines in left ventricular ejection fraction, which normalised during follow-up. Two patients died before surgery. With a median follow-up of 60.7 months, five-year locoregional recurrence-free survival was 100%, disease-free survival 95%, distant metastasis-free survival 95% and overall survival 95%. Two patients (3%) developed an independent contralateral primary tumour and three had distant recurrence. Cosmetic results were rated excellent or good in all breast-conserving cases, and among the 19 patients who underwent mastectomy, reconstruction was performed in 11, with better outcomes for autologous than heterologous techniques.
What it means
The authors conclude that this strategy showed encouraging local control and survival, with acceptable toxicity in selected patients, but stress that it is a pilot study and that larger randomised trials are needed to confirm it. For a patient, it is worth underlining that this is an investigational approach and not a standard; for breast units, it suggests the value of further exploring preoperative radiotherapy in specific subtypes and of looking after coordination with reconstructive surgery.
Spanish context
This is a single-centre pilot study carried out in Spain, reflecting the capacity of the country’s radiation oncology and medical oncology departments to develop preoperative treatment programmes in high-risk subtypes. Projects of this kind require close multidisciplinary collaboration within the breast unit, with coordinated input from radiotherapy, surgery, medical oncology and pathology, and with PET-CT as a planning tool.
Reference: Ciérvide R, Montero Á, García-Aranda M, Valero J, Álvarez B, Chen X, et al. Long-term results of preoperative hypofractionated chemoradiotherapy for high-risk HER2-positive and triple-negative breast cancer subtypes. Clinical & Translational Oncology, 2026. DOI
