ESTRO 2025 Congress report
By the reirradiation focus group (report #3/5)

1. ReCare cohort study: real-world reirradiation patterns
   Mini-Oral
   Presenter: Jonas Willmann

The ReCare study, part of the larger E2-RADIatE initiative, aims to provide real-world data on reirradiation practices across Europe and Asia. This prospective observational cohort includes patients who have undergone high-dose reirradiation for thoracic, abdominal, or pelvic malignancies in 14 hospitals across 10 countries.

Between May 2023 and October 2024, 243 patients with 280 lesions were enrolled. The most frequently treated regions were the thorax (49.6%), pelvis (35%), and abdomen (13.6%), with prostate (35.5%), lung (27.3%), and breast (23.6%) cancers being the most common primary tumours. Most patients received type 1 reirradiation (with volume overlap, 80.7%) and a median EQD2 dose of 61.9Gy across a median of five fractions. Photon therapy was predominantly used (93.6%); particle therapy and brachytherapy were rarely employed.

Reirradiation completion rates were high (96.4%). A total of 29.2% underwent surgery prior to reirradiation. About a third received concurrent systemic therapy, primarily with hormonal agents. Imaging was often guided by PET/CT, and 35% of lesions were biopsy-confirmed.

This interim analysis confirms the feasibility of pan-European prospective data collection in reirradiation and highlights heterogeneous treatment approaches in clinical practice. It supports future data-driven evaluations of efficacy, toxicity, and quality of life outcomes, and an expansion to head-and-neck/central nervous system reirradiation cohorts.

 

Jonas Willmann

2. RE-START registry: reirradiation after radiotherapy of the prostate
   Poster discussion
   Presenter: Giulio Francolini, Careggi University Hospital, Florence, Italy

 

The RE-START registry is a multicentre initiative supported by the Italian Association of Radiation Oncology (AIRO), which is aimed at collecting retrospective data on reirradiation in patients previously treated with postoperative or definitive radiotherapy for prostate cancer. The goal is to assess the safety and outcomes of reirradiation in real-world settings.

Data from 433 patients treated in five centres across Italy and Poland showed a diverse use of reirradiation techniques: intensity-modulated radiotherapy (IMRT) (57%), stereotactic radiotherapy (37%), and brachytherapy (6%). Androgen deprivation therapy (ADT) was co-administered in 55% of cases. Toxicity was low: acute grade ≥3 gastrointestinal (GI) and genito-urinary (GU) toxicity occurred in only 0.2% and 0.5% of cases, respectively. Long-term grade ≥3 toxicities were reported in 2.1% (GI) and 8.5% (GU) of cases.

Survival outcomes were promising: median biochemical relapse-free survival (BRFS) was 34 months, metastasis-free survival 118 months, and OS 109 months. The use of prostate-specific membrane antigen imaging and early treatment before the development of castration resistance was associated with improved rates of BRFS. Conversely, outcomes were worse in castration-resistant patients.

This study demonstrates that reirradiation is a viable, safe salvage option for local recurrence in prostate cancer that may delay the need for lifelong ADT.

 

 

 

Dr Bartek Tomasik
Department of Oncology and Radiotherapy, Faculty of Medicine
Medical University of Gdańsk
Gdańsk, Poland
Member of the ESTRO reirradiation focus group
ESTRO 2025 Social media ambassador for reirradiation
bartlomiej.tomasik@gumed.edu.pl
LinkedIn: Bartłomiej Tomasik
X: https://x.com/B_Tomasik (@B_Tomasik)

 

 

Dr. Gian Marco Petrianni
Operative Research Unit of Radiation Oncology
Fondazione Policlinico Universitario Campus Bio-Medico
Rome, Italy
Member of the ESTRO reirradiation focus group
ESTRO 2025 Social media ambassador for reirradiation
g.petrianni@policlinicocampus.it
LinkedIn: Gian Marco Petrianni
X: Gian Marco Petrianni