ESTRO 37 Abstract book

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ESTRO 37

for pts treated without SIB and 10.9 (1.7-78.8) months with SIB. One patient, treated with SIB, was alive at the last follow up (October 2017), 78.8 months after the end of HTT. Ten pts died within 3 months of the beginning of HTT. BTV volume ≥ 473 cc was the only predictor of early death: 60,8% of pts lived more than 10 months, 31.4% more than 20 months, 11.8% more than 30 months and 5.9% more than 50 months. Third and 4th stage pts with BTV volume ≤ 204.6 cc treated with SIB had a better survival (20.4 vs 9.2 months, p= 0.015). One patient died three weeks after the end of therapy, with fever and worsening dyspnea, despite the antibiotics and oxygen therapy. Three other G2 and 1 G3 acute pneumonitis were registered. Two G2 and 7 G3 late pneumonitis were registered, 3 with limited duration of oxygen therapy prescription. One patient, with type 2 Diabetes, died with CT evidence of bilateral actinic pneumonia and without progressive disease, 6.9 months after the end of HTT. BTV ≤ 204.6 cc was predictive of late G≥2 radiation pneumonitis (pulmonary function not yet compromised by MPM). Conclusion With salvage FDG-PET/CT guided helical IG- IMRT in pts with progressive MPM the median survival was similar to those obtained in series using extrapleural pneumonectomy or P/D and adjuvant chemotherapy and radiotherapy (Rosenzweig et al, Int J Radiat Oncol Biol 2011, 83:1278). G≥2 late pneumonitis rate and fatal toxicities are similar to other published series and depend on BTV volume. Results suggest that RT may be delayed, as a salvage, without losing survival, but postponing toxicity. EP-1391 EGFR/ALK Mutations in Stage III Non-small Cell Lung Cancer Patients Received Chemoradiotherapy S.F. Nyaw 1 , W.Y. Tin 2 , S.H. Lo 2 , Y. Tung 2 1 Tuen Mun Hospital, Department of Clinical Oncology, New Territories, Hong Kong SAR China 2 Tuen Mun Hospital, Department of Clinical Oncology, Hong Kong, Hong Kong SAR China Purpose or Objective EGFR and ALK mutation are biomarkers predictive of favorable outcomes in metastatic non-small cell lung cancer (NSCLC). Its prognostic value in stage III NSCLC is less clear. The objective of this study is to study the association of EGFR and ALK mutations with clinical outcome in stage III NSCLC patients treated with concurrent chemoradiotherapy. Material and Methods 98 patients with stage III non-small cell lung cancer who received concurrent chemoradiotherapy from January 2008 to March 2017 were retrospectively identified. Activated EGFR and ALK mutations were detected in 20 and 4 patients respectively. Kaplan-Meier method was used to conduct the progression-free survival (PFS) and overall survival (OS) analyses. Results 55 (56%) patients had stage IIIA and 43(44%) patients had stage IIIB disease. Majority (76%) of patients received radiation dose of 60Gy (range 50-66Gy). The most common histology was adenocarcinoma (54%) followed by squamous cell carcinoma (28%). The median follow up time was 66 months. The median progression-free survival (PFS) was 13.3 months and the median overall survival (OS) was 29.3 months. Among the 24 patients with activated EGFR mutation, 21(88%) of them had disease progression. 95% (20/21) of them developed distant metastasis as the first site of disease progression. All patients subsequently received EGFR or ALK targeted therapies upon disease progression. In patients with EGFR/ALK mutations, the 2-year progress-free survival probability was 25% and the 5-year overall survival probability was 13%. Among patients with

non-squamous histology, the median PFS was 11.6 months in patients with EGFR/ALK mutations compared with 12.5 months in patients without mutation (p=0.78). The median OS was 30.7 months in patients with EGFR/ALK mutations vs 28.6 months in patients without mutations (p=0.45). Conclusion Although EGFR and ALK mutation were known to be associated with favourable outcome in metastatic non- small cell lung cancer, they were not shown to be significant prognostic factors in patients with stage III non-small cell lung cancer who received concurrent chemoradiotherapy. The risk of distant metastasis in patients with EGFR/ALK mutation was very high and the 5-year overall survival of them was poor. EP-1392 Trimodality treatment of Stage III non-small cell lung cancer in Western Australia J. Croker 1 , M. Ariyapperuma 2 , S. Sharma 3 , S. Mukhedkar 4 , W.S. Lam 2 , T. Lim 1 1 Fiona Stanley Hospital, Department of Radiation Oncology, MURDOCH, Australia 2 Fiona Stanley Hospital, Department of Medical Oncology, MURDOCH, Australia 3 Fiona Stanley Hospital, Department of Cardiothoracic Surgery, MURDOCH, Australia 4 St John of God Medical Centre, Department of Medical Oncology, MURDOCH, Australia Purpose or Objective To assess the outcomes of patients with Stage III Non- Small Cell Lung Cancer (NSCLC) undergoing trimodality therapy (neoadjuvant chemoradiotherapy followed by definitive surgery) in tertiary Western Australian cancer centres Material and Methods Patients with biopsy proven Stage III NSCLC were assessed in a lung cancer multidisciplinary clinic. Patients of good performance (ECOG 0-1) deemed fit for radical treatment but whose tumours were borderline resectable were offered treatment with neoadjuvant chemoradiation (CRT), followed by assessment of response to treatment prior to curative intent surgery. Neoadjuvant CRT consisted of cisplatin and etoposide in combination 3D conformal or intensity modulated radiotherapy, delivered to a total dose of 45-50 Gy in 25 fractions. Restaging PET and CT scans were performed 3- 4 weeks post-neoadjuvant CRT. Patients with good tumour response were offered lobectomy and mediastinal lymph node dissection, while those with progressive local disease (PD) or deemed unresectable were offered consolidative radiotherapy dose of 20-24 Gy in 10-12 fractions. Pathology specimens were examined for response to neoadjuvant treatment. Patients were followed 3 monthly or until death with examination and imaging at clinician discretion. Data was retrospectively collected for all patients treated from February 2010 to October 2017. Analysis was made of response to neoadjuvant treatment, survival, disease recurrence and pattern of recurrence. Results Thirty-one patients were planned to undergo trimodality treatment. Eighty four percent of patients were male and 14% female. The median age was 65 years (range 48-75 years). Two patients (6%) had Stage IIIB disease and the remaining 29 (94%) patients had Stage IIIA disease. All except one patient had node positive disease. Median tumour size was 40mm (range 15-84mm). Twelve (39%) of patients had squamous cell carcinoma, 17 had adenocarcinoma (55%) and 2 had mixed adenosquamous (6%) histopathology. All patients completed their CRT. Twenty-two patients (71%) underwent surgical resection. Of the nine patients who did not have surgery, four underwent consolidation