ESTRO 2024 - Abstract Book

S1680

Clinical - Lung

ESTRO 2024

Among 123 patients, 30 fulfilled the criteria of prior lung surgery and/or radiotherapy (surgery only: 57%, radiotherapy only: 30%, surgery and radiotherapy: 13%) with a coexisting lung disease (87% COPD, 10% pulmonary fibrosis, 3% others). Mean/median age was 74/75 years (range 59-86). The pre-SBRT image-based staging confirmed 29 T1 tumors (T1a: 3/30, T1b:17/30, T1c:9/30) and one T2a tumor, with a mean/median PTV volume of 19.1/12.4 cc (range 6.3-72.8) for T1 and 111.5 cc for the T2 tumor, respectively. 90% of patients lacked histological confirmation due to age or comorbidities, while 80% had undergone FDG-PET/CT assessments. 13% required supplemental oxygen before SBRT. The mean/median follow-up after SBRT was 21.7/24 months (range 0-45). In 2 out of 30 patients, a reduced dose was administered due to significantly impaired lung function, while the remaining patients received one of the above mentioned standard fractionations. In 5/30 patients (16%), there was suspicion of radiation induced toxicity: two with symptomatic Grade 2 pneumonitis, that were successfully treated with steroids; three patients had radiologic findings without clinical symptoms: one with organizing pneumonia, one with atelectasis of the SBRT-related middle lobe, and one with a likely post-radiotherapeutic insufficiency fracture of the rib.

After a median FU of 24 months, the local control rate was 94.7%. Only one patient (3%) developed local progression and one patient developed distant metastases and died of disease.

Conclusion:

This analysis demonstrates high tolerance and efficacy of lung SBRT in a cohort of previously treated lung cancer patients with impaired lung function, highlighting the potential of SBRT in managing recurrent or secondary lung malignancies in patients with pulmonary limitations.

Keywords: SBRT, stereotactic

1594

Poster Discussion

Oesophageal toxicity in the phase 2 PET-Boost dose-escalation trial (NCT01024829) in LA-NSCLC

Saskia A Cooke 1 , José S.A. Belderbos 1 , Barbara Stam 1 , Bart Reymen 2 , Maarten Lambrecht 3,4 , Gitte Fredberg Persson 5,6,7 , Corinne Faivre-Finn 8 , Edith Dieleman 9 , Judi van Diessen 1 , Dirk de Ruysscher 2 , Jan-Jakob Sonke 1 1 Netherlands Cancer Institute (NKI-AVL), Radiation Oncology, Amsterdam, Netherlands. 2 MAASTRO Clinic, GROW – School for Oncology and Developmental Biology, Maastricht University Medical Center, Radiation Oncology, Maastricht, Netherlands. 3 KU Leuven – University of Leuven, Oncology, Experimental Radiation Oncology, Leuven, Belgium. 4 University Hospitals Leuven, Radiotherapy-Oncology, Gasthuisberg, Belgium. 5 Copenhagen University Hospital - Rigshospitalet, Oncology, Copenhagen, Denmark. 6 Copenhagen University Hospital – Herlev and Gentofte, Oncology, Copenhagen, Denmark. 7 University of Copenhagen, Clinical Medicine, Copenhagen, Denmark. 8 University of Manchester, The Christie NHS Foundation Trust, Clinical Oncology, Manchester, United Kingdom. 9 Amsterdam University Medical Centers location AMC, Radiation Oncology, Amsterdam, Netherlands