S266
Clinical - Breast
ESTRO 2026
G3 fatigue, no >G3 was recorded. Patients receiving ultrahypofractionated RT showed no >G1 acute side effects. For 53 patients with a 6-months follow-up, one G2 skin side effect and no >G2 was recorded Conclusion: analyzing 130 BC patients treated with adiuvant RT in the last 14 months at our institution, we noticed that normofractionated RT is nowadays limited to selected cases, i.e. reirradiation or left-side complete nodal irradiation. After ESTRO 2025, where long-term follow- up of the FAST-Forward was presented, we started to use ultrahypofractionated RT as standard treatment for adjuvant RT for invasive BC, with good results in terms of acute adverse events. However, longer follow-up is needed. Keywords: breast cancer, ultrahypofractionated RT Single-fraction stereotactic boost in high-risk early breast cancer: safety and early toxicity results of a phase II trial Giuseppe Facondo 1 , Agnese Prisco 1 , Chiara Reverberi 1 , Tino Ceschia 1 , Eleonora Festa 1 , Gianluca Vullo 1 , Francesca Titone 1 , Fabrizio Tonetto 1 , Margherita Polsinelli 1 , Marco Andrea Signor 1 , Germana Chiaulon 1 , Giuseppe Parisi 1 , Marika Guernieri 2 , Vito Gagliardi 2 , Daniela Marfisi 2 , Sarah Bassi 2 , Claudio Foti 2 , Paolo Scalchi 2 , Eugenia Moretti 2 , Marco Trovo 1 1 Radiation Oncology, Santa Maria della Misericordia, Udine, Italy. 2 Medical Physics, Santa Maria della Misericordia, Udine, Italy Poster Discussion 2165 Purpose/Objective: To evaluate acute and late moderate/severe toxicity of a single-fraction stereotactic boost to the surgical cavity using GammaPod™ in early-stage breast cancer patients at high risk of local recurrence. Material/Methods: This is a prospective, single-arm phase II study including 70 women with early-stage breast cancer meeting high-risk criteria (age ≤ 50 years, triple- negative/basal-like subtype, G3, or non-re-excisable close/positive margins).Following breast-conserving surgery, patients underwent a single-fraction stereotactic boost using GammaPod™ system, delivered the day before starting whole-breast irradiation, consisting in 40 Gy in 15 daily fractions.A single dose of 7.5 Gy was delivered under stereotactic localization to the 95% of the planning target volume (PTV). Imaging, planning and dose delivery were mostly completed within a 1-hour session. The primary endpoint was grade ≥ 2 late toxicity. Secondary endpoints included local recurrence (LR), distant metastasis-free survival (MFS) and overall survival (OS). The Kaplan-Meier method was used to
Digital Poster 2083 Real-world clinical practice fractionation shift in adjuvant radiotherapy for breast cancer Chiara De Colle 1 , Andrea Gaetano Allegra 1 , Luca Nicosia 1 , Niccolò Giaj-Levra 1 , Edoardo Pastorello 1 , Francesco Ricchetti 1 , Michele Rigo 1 , Carolina Orsatti 1 , Andrea Romei 1 , Nicola Bianchi 1 , Riccardo Filippo Borgese 1 , Antonio De Simone 1 , Davide Gurrera 1 , Stefania Stefania 1 , Gianluisa Sicignano 1 , Ruggero Ruggieri 1 , Filippo Alongi 1,2 1 Department of Advanced Radiation Oncology, IRCCS Sacro Cuore Don Calabria Hospital, Cancer Care Center, Negrar, Italy. 2 University of Brescia, University of Brescia, Brescia, Italy Purpose/Objective: Adjuvant radiotherapy (RT) remains a milestone in the treatment of breast cancer (BC) patients. Over the years, phase III studies provided high-level evidence supporting the use of hypofractionation and ultrahypofractionation in this setting. We here present fractionation clinical practice changes based on real- world data in an Italian cancer care center Material/Methods: between July 2024 and September 2025, 130 patients with early-stage or locally-advanced BC were treated in our center and considered for this analysis. Clinical and treatment characteristics, with a focus on fractionation schedules, were analyzed. Acute and early-late adverse events were reported Results: All patients were female, with mean age of 63 years (range, 30-89). Breast conservative surgery was performed in 109 patients, mastectomy in 19 and surgical excision for tumour relapse after previous mastectomy in 2. Sentinel lymphnode excision was performed in 96 patients, axillary dissection in 25, 9 with non-invasive BC received no axillary surgery. Early-stage BC was found in 95 patients and locally advanced in 35. Eighty-one had luminal A tumours, 22 luminal B/Her2 negative, 9 luminal B/Her2 positive, 4 hormonal negative/Her-like and 13 triple negative. IMRT was used for the great majority, 32 were treated with deep-inspiration breath-hold technique. Five patients received partial breast irradiation. Eleven patients received 50-50.4 Gy (+/- boost to 60 Gy) in 25- 30 fractions, 98 received 40.5 Gy (+/- boost to 48 Gy) in 15 fractions and 18 received 26 Gy in 5 fractions. All ultrahypofractionations were performed after May 2025. The normofractionated courses were one case of reRT and 10 with left-side lymphnodal irradiation including internal mammary chain. After May 2025, hypofractionated RT was limited to patients with thoracic wall + /- lymphnode irradiation, patients with non-invasive BC or very young patients. Grade 2 acute side effects were recorded in 15 patients, one showed
Made with FlippingBook - Share PDF online