ESTRO 2022 - Abstract Book

S526

Abstract book

ESTRO 2022

Patients with synchronous or metachronous distant metastases from esophagogastric cancer were screened for de-novo OMD between 2015 and 2020. De-novo OMD was defined as ≤ 5 distant metastases detected with 18 F-FDG-PET/CT imaging. Treatment for OMD was categorized into (1) local treatment, comprising of metastasectomy or stereotactic radiotherapy (SRT) with or without systemic therapy, (2) systemic therapy alone, or (3) best supportive care (BSC). Systemic therapy included chemotherapy, targeted therapy, or immunotherapy. The primary outcome was OS expressed with 95% confidence intervals (CIs). OS was calculated from the first diagnosis of OMD and was compared using log-rank test. Results A total of 447 patients with distant metastases from esophagogastric cancer were screened of whom 116 patients (26%) with de-novo OMD were included. The incidence of de-novo OMD was comparable between the two centers (25% versus 28%; Figure 1). The majority of included patients had adenocarcinomas (88%) of the esophagus (74%), and synchronous OMD (57%). The number of OMD lesions was 1 (57%), 2 (22%), 3 (10%), or >3 (11%). Treatment for OMD was local treatment with or without systemic therapy (53%), systemic therapy alone (33%), or BSC (14%). Median follow-up time was 13 months (interquartile range: 7-26). OS was 23.0 months (95% CI: 18-58) after local treatment for OMD with or without systemic therapy, 11.0 months (95% CI: 9-29) after systemic therapy alone, and 7.5 months (95% CI: 4-NA) in patients having received BSC (p<0.0001; Figure 2).

Conclusion The incidence of OMD in patients with esophagogastric cancer was comparable between the two centers in this international multicenter study. Metastasectomy or SBRT for OMD (with or without systemic therapy) was associated with better OS in this selected cohort.

OC-0602 A pREDictive model of polymetastatic disease on oligometastatic colorectal cancer: the RED LaIT-SABR

L. Nicosia 1 , D. Franceschini 2 , F. Perrone Congedi 3 , F. Casamassima 4 , M.A. Gerardi 5 , M. Rigo 1 , R. Mazzola 1 , M. Perna 6 , V. Scotti 7 , A. Fodor 8 , A. Iurato 9 , F. Pasqualetti 10 , G. Gadducci 10 , S. Chiesa 11 , R.M. Niespolo 12 , A. Bruni 13 , G. Alicino 13 , L. Frassinelli 13 , P. Borghetti 14 , A. Di Marzo 15 , A. Ravasio 16 , B. De Bari 17 , M. Sepulcri 18 , D. Aiello 19 , G. Mortellaro 20 , C. Sangalli 21 , M. Franceschini 21 , G. Montesi 22 , F.M. Aquilanti 23 , G. Lunardi 24 , R. Valdagni 21 , I. Fazio 19 , L. Corti 25 , V. Vavassori 26 , E. Maranzano 27 , S.M. Magrini 14 , S. Arcangeli 13 , V. Valentini 11 , F. Paiar 10 , S. Ramella 9 , N.G. Di Muzio 8 , L. Livi 6 , B.A. Jereczek- Fossa 5 , M.F. Osti 3 , M. Scorsetti 28 , F. Alongi 29 1 IRCCS Sacro Cuore Don Calabria Hospital, Cancer Care Center, Advanced Radiation Oncology Department, Negrar, Italy; 2 IRCCS Humanitas Research Hospital, Radiation Oncology Department, Milan, Italy; 3 "Sapienza" University, Sant'Andrea Hospital, Department of Radiation Oncology, Rome, Italy; 4 Ecomedica Radioterapia, Radioterapia, Empoli, Italy; 5 IEO European Institute of Oncology IRCCS, Division of Radiation Oncology, Milan, Italy; 6 Azienda Ospedaliera Universitaria Careggi, University of Florence, Radiation Oncology Unit, Florence, Italy; 7 Azienda Ospedaliera Universitaria Careggi, University of Florenc, Radiation Oncology Unit, Florence, Italy; 8 IRCCS San Raffaele Scientific Institute, Department of Radiation Oncology, Milan, Italy; 9 Campus Bio-Medico University, Radiation Oncology, Rome, Italy; 10 Pisa University Hospital, Radiation Oncology Unit, Pisa, Italy; 11 Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radioterapia Oncologica, Rome, Italy; 12 Azienda Ospedaliera S. Gerardo, Department of Radiation Oncology, Monza, Italy; 13 University Hospital of Modena, Radiotherapy Unit, Modena, Italy; 14 ASST Spedali Civili di Brescia - Brescia University, Radiation Oncology Department, Brescia, Italy; 15 S. Maria Hospital, Terni, Radiation Oncology Centre, Terni, Italy; 16 Humanitas Gavazzeni, Bergamo, Radiotherapy Unit, Bergamo, Italy; 17 University Hospital of Besançon, Besançon, Radiation Oncology Department, Besançon, France; 18 Veneto Institute of Oncology IOV-IRCCS, Padua, Radiation Oncology Unit, Padua, Italy; 19 Casa di Cura Macchiarella, Radiotherapy Unit, Palermo, Italy; 20 ARNAS Ospedale Civico, Department of Radiation Oncology, Palermo, Italy; 21 Fondazione IRCCS Istituto Nazionale dei Tumori, Department of Radiation Oncology 1, Milan, Italy; 22 ULSS5, Radiotherapy Unit , Rovigo, Italy; 23 Marrelli Hospital, Radiotherapy Marrelli Hospital, Crotone, Italy; 24 IRCCS Sacro Cuore Don Calabria Hospital, Medical Analysis Laboratory, Negrar, Italy; 25 Veneto Institute of Oncology IOV-IRCCS, Radiation Oncology Unit, Padua, Italy; 26 Humanitas Gavazzeni, Radiotherapy Unit, Bergamo, Italy; 27 S. Maria Hospital, Radiation Oncology Centre, Terni, Italy; 28 IRCCS Humanitas Research Hospital, Radiotherapy, Milan, Italy; 29 IRCCS Sacro Cuore Don Calabria Hospital, Advanced Radiation Oncology Department, Negrar, Italy