ESTRO 37 Abstract book

S15

ESTRO 37

3 Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands

Figure 1 a-b: NTCP models for the probability of grade 1- 2 acute toxicity in the esophagus

This abstract is part of the media programme and will be relased on the day of its presentation PV-0040 Patterns of care for the elderly with non- surgically treated stage III non-small cell lung cancer E.D. Miller 1 , J.L. Fisher 2 , K.E. Haglund 1 , J.C. Gre cula 1 , M. Xu-Welliver 1 , E.M. Bertino 3 , K. He 3 , P.G. Shields 3 , D.P. Carbone 3 , T.M. Williams 1 , G.A. Otterson 3 , J.G. Bazan 1 1 Ohio State University Wexner Medical Center, Department of Radiation Oncology, Columbus, USA 2 Ohio State University, College of Public Health, Columbus, USA 3 Ohio State University Wexner Medical Center, Department of Internal Medicine- Division of Medical Oncology, Columbus, USA tients versus younger patients with stage III non-small cell lung cancer (NSCLC) not treated surgically using the National Cancer Database (NCDB). We hypothesize that elderly patients are less likely to receive curative treatments, including concurrent chemoradiation (CCRT), compared to younger patients. Material and Methods We identified patients from the NCDB between 2003 and 2014 with non-surgically treated stage III NSCLC. We defined elderly as ≥70 years old and non-elderly as <70 years old. We categorized patients as having no treatment, palliative treatment (chemotherapy alone, radiation therapy (RT) alone<59.4 Gy or chemoradiation (CRT)<59.4 Gy), or definitive treatment (RT alone≥59.4 Gy or CRT≥59.4 Gy). Patients treated with CRT were further subdivided into those receiving CCRT vs. those treated with sequential CRT (SCRT). CCRT was defined as chemotherapy delivered within 30 days prior to or after initiation of RT while SCRT was defined as RT delivered >30 days after initiation of chemotherapy. Differences in treatment between the elderly and non-elderly were tested using the χ 2 test. Results We identified 57,602 elderly and 55,928 non-elderly patients. The mean age was 77.5 years (SD=5.3) in the elderly and 60.2 years (SD=7.0) in the non-elderly. The elderly were less likely (1) to have no comorbidities (57.7% vs. 62.9%, p<.0001), (2) to be treated at academic centers (25.5% vs. 30.3%, p<.0001), and (3) to have stage IIIB disease (44.5% vs. 50.0%, p<.0001) compared to non- elderly patients. More elderly patients received no treatment (24.5% vs. 13.2%, p<.0001) and the elderly were less likely to receive definitive treatment (51.1% vs. 59.7%, p<.0001). Chemotherapy as part of a definitive treatment course was included less often in the elderly: 21.1% of the elderly received definitive RT alone compared to 6.5% for the non-elderly, p<.0001. In patients receiving definitive CRT, a higher proportion of the elderly received SCRT compared to the non-elderly (16.3% vs. 15.4%, p=.016). Overall, CCRT was delivered in a significantly smaller proportion of elderly vs. non- elderly patients (66.0% vs. 78.9%, p<.0001 in patients treated with definitive intent; 32.0% vs. 44.5%, p<.0001 in patients receiving any treatment; and 24.2% vs. 38.6%, p<.0001 amongst all patients). Conclusion In this large study of patients with stage III NSCLC not treated surgically, elderly patients were less likely to receive any treatment or treatment with definitive intent compared to the non-elderly. When a definitive treatment course was delivered, more than 20% of Purpose or Objective To compare patterns of care for elderly pa

Conclusion As no grades 3-5 esophagus toxicity were observed in our cohort, we conclude that a D max of 60.0 Gy 10 (5 x 8 Gy) and a D 1cc of 49.6 Gy 10 (5 x 7 Gy) can be safely delivered using stereotactic radiotherapy. The NTCP-curves derived may serve as guidelines for central lung cancer undergoing stereotactic treatment. PV-0039 Outcome of elderly NSCLC patients treated with isotoxic RT dose-escalation using IMRT (NCT01166204) J. Van Loon 1 , D. De Ruysscher 1 , S. Peeters 1 , K. Verhoeven 1 , G. Bootsma 2 , A.C. Dingemans 3 , A. Van Baardwijk 1 , B. Reymen 1 , R. Wanders 1 1 MAASTRO Clinic, Radiation Oncology, Maastricht, The Netherlands 2 Zuyderland Medical Centre, Pulmonology, Heerlen, The Netherlands