ESTRO 2024 - Abstract Book

S1699

Clinical - Lung

ESTRO 2024

1814

Poster Discussion

First line CT-IT followed by thoracic RT in ES-SCLC:a retrospective multicenter study on safety

Alessio Bruni 1 , Federica Bertolini 2 , Vieri Scotti 3 , Paolo Borghetti 4 , Matteo Sepulcri 5 , Mirsada Katica 4 , Jessica Imbrescia 1 , Niccolo Giaj Levra 6 , Salvatore Grisanti 7 , Anna Benini 1 , Anna Cappelli 1 , Pietro Garlatti 3 , Giorgia Guaitoli 8 , Massimo Dominici 9 , Frank Lohr 1 1 University Hospital of Modena, Department of Oncology and Ematology - Radiotherapy Unit, Modena, Italy. 2 University Hospital of Modena, Department of Oncology and Hematology,Division of Oncology,, Modena, Italy. 3 University Hospital "Careggi", Radiation Oncology Unit, Oncology Department AOU Firenze, Florence, Italy. 4 ASST Spedali Civili and University of Brescia, Radiation Oncology Department, Brescia, Italy. 5 Veneto Oncological Institute (IOV-IRCCS), Radiation Therapy Unit, Padua, Italy. 6 IRCCS Sacro Cuore Don Calabria Hospital - Cancer Care Center, Advanced Radiation Oncology Department, Verona, Italy. 7 ASST Spedali Civili and University of Brescia, Medical Oncology Department, Brescia, Italy. 8 University of Modena and Reggio Emilia, PhD Program Clinical and Experimental Medicine, Modena, Italy. 9 University of Modena and Reggio Emilia - Division of Oncology, Department of Medical and Surgical Sciences for Children and Adults, Modena, Italy

Purpose/Objective:

Recently, the addition of immunotherapy to first line chemotherapy-immunotherapy (CT-IT) improved clinical outcomes of patients with ES-SCLC without worsening systemic tolerance. Even if cTRT is suggested in select patients by some international recommendations, its general safety and feasibility has still not been prospectively explored explicitely. The aim of this retrospective study was to evaluate the safety of the combination of first line CT-IT with cTRT using modern techniques in ES-SCLC patients

Material/Methods:

One hundred-three patients were treated in five northern Italian centers from February 2020 to March 2023 and were retrospectively analyzed. Median age was 67 years (range 38-84). Fifty-nine (57.2%) were male and 44 (42.8%) were female. All pts had ECOG PS 0-1, except for 11 pts with PS=2 (10.6%). Fifty-two patients (50.4%) were current smokers, 47(45.6%) former smokers and 4 (3%) non smokers. At time of treatment, all pts had histologically proven ES-SCLC. Twenty-two (21.3%) and 34 (33.0%) patients had brain and liver metastasis, respectively: seven patients had both. Immune- and radiotherapy related side effects were collected based on the CTCAE 4.0 scale. Overall and progression free survival were also reported using the Kaplan Meier method.

Results:

At a median follow up of 11 months (range 2-39), 103 pts with ES-SCLC underwent platinum-based CT-IT followed by maintenance IT with atezolizumab. Consolidative TRT was delivered to 33 (32.1%) responding pts (31 pts received 30-45 Gy in 10-15 sessions and two patients were treated with radical doses (55 Gy in 27 and 60 Gy in 30 sessions), and 14 of those pts underwent prophylactic cranial irradiation (25 gray in 10 fractions in all patients).Seventeen pts