ESTRO 38 Abstract book

S755 ESTRO 38

patients had recurrences: local (n=2), lobar (n=1), regional (n=2), distant (n=6), local and regional (n=1), local, regional and distant (n=1). SVM model found that HISTO_Kurtosis and GLRLM_LRLGE can describe patients with any disease recurrence (AUC=0.65). A cutoff of HISTO_Kurtosis=2.5 obtained with log-rank test was able to classify the population in high and low recurrence risk (p=0.03). Conclusion Among baseline 18F-FDG PET/CT textural feature, HISTO_Kurtosis and GLRLM_LRLGE confirmed as predictors of RFS in our analysis. Although this needs further validation on a larger series of patients, it may reveal helpful in identifying patients who will benefit from closer surveillance or adjuvant therapy. EP-1383 Cytokine profile of NSCLC patients treated with chemoradiotherapy regarding to radiation pneumonitis EP-1384 Analysing stage III cN2 NSCLC treated with surgery or concurrent chemo-radiation P. Lyons 1 , H.W.G. Gan 1 , C.W.E. Chan 1 , E. McCully 1 , S. Ansel 1 , M. Philip 1 , N. Mohammed 1 1 Beatson West Of Scotland Cancer Centre, Clinical Oncology, Glasgow, United Kingdom Purpose or Objective Non-small cell lung cancer (NSCLC) patients with stage 3 N2 disease are a heterogeneous group of patients who are offered surgery or chemo-radiotherapy. ESMO lung cancer guideline recommends consideration of surgery for early stage NSCLC – cT1-3 N0-cN2 M0. And inoperable, locally advanced patients are treated with radical chemo- radiation (CRT) if permissible. This study investigated the outcomes of stage 3 N2 patients either diagnosed after surgery or before CRT in order to compare their survival outcomes. Material and Methods Patients with stage cN2 NSCLC diagnosed from January 2013 to January 2016, and treated with chemo-radiation or patients who underwent lung resection and had a diagnosis of pN2 in the West of Scotland were identified. A retrospective audit of patients was performed. Results We identified 161 patients with pN2 diagnosis after lung resection and 107 patients with cN2 diagnosis treated with concurrent chemo-radiation. The demographic data was similar between the surgical and CRT group except that the surgical pN2 group had prior clinical staging of cN0 (43%), cN1 (25%) and cN2 (31%) as opposed to CRT patients, which were all cN2. In addition, only 88 patients (54%) of the surgical pN2 group were given adjuvant chemotherapy as opposed to all CRT cN2 patients. The median overall survival (OS) of the surgical pN2 group was not significantly different compared with the more advanced cN2 CRT patients who had median survival 19.9 months (95% CI 14.6-26.4m), However, median OS in patients with surgical pN2 who received adjuvant chemotherapy had significantly higher overall survival than surgery alone – 30.2 months versus 17.6 months (95% CI 12.3-22.6m) (p=0.003) (Figure 1). Abstract withdrawn

Conclusion It is clear that NSCLC patients with pN2 disease (includes cN0-2) are not comparable with cN2 patients in terms of burden of disease. Yet our study demonstrated that median OS was not statistically different. This was because 43% patients were cN0 and were considered fit for surgery but not chemotherapy, resulting in 46% of pN2 patients not given adjuvant chemotherapy. Hence, further investigation of the mediastinal nodal staging is warranted and possibly to reconsider mediastinal staging of PET negative nodes. In addition, patients considered for surgery should be assessed in terms of fitness for both surgery and chemotherapy or else be considered for chemo-radiation. EP-1385 Does pneumonitis increase in irradiated lungs during immunotherapy?A generating hypotheses study C. Mazzarella 1 , A. Martino 2 , A.R. Alitto 1 , F. Preziosi 2 , F. Catucci 1 , A. Petrone 1 , M. Campitelli 1 , F. Marazzi 1 , G.C. Mattiucci 2 , G. Palazzoni 2 , V. Valentini 2 , G. Mantini 2 1 Fondazione Policlinico Universitario A. Gemelli IRCCS, Scienze Radiologiche- Radioterapiche ed Ematologiche, Rome, Italy ; 2 Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Scienze Radiologiche- Radioterapiche ed Ematologiche, Rome, Italy Purpose or Objective Immunotherapy with immune checkpoint inhibitors (ICIs) revolutionized therapy of advanced non-small-cell lung cancer (NSCLC) . Nivolumab have been shown to improve overall survival in advanced, metastatic patients (pts) with NSCLC. Nevertheless, immune-related pneumonitis is a potentially fatal toxicity of anti-PD-1/PD-L1. This study investigates the role of chest radiotherapy (RT) and the development of immune-related pneumonitis in NSCLC Consecutive patients with locally-advanced or metastatic NSCLC treated with nivolumab as second or third-line therapy for recurrent or progressive disease, between May 2017 and March 2018 were included. Patient demographics, treatment, adverse event and RT data including type of RT, volume of RT and number of courses were collected. Toxicity was evaluated according to the common terminology criteria for adverse events (CTCAE) version 4.0. Results Seventeen patients were treated, mostly male (65%), current or former smokers (76.5%) with Eastern Cooperative Oncology Group (ECOG) PS score <2 (88%). Median age was 67 years (range: 49-79). Previously 15/17 (88.2%) patients had undergone radiotherapy on the thoracic disease or for metastatic sites. Mean number of nivolumab cycles was 12 (range: 1-26). 11/17 (64.7%) patients had only locally-advanced disease. Of 15 patients who received any RT, we observed 3/15 (20%) G2/G3 pneumonitis and 1/15 (6.6%) G4. Only 1/4 (25%) pneumonitis occurred in RT field. treated with nivolumab. Material and Methods