ESTRO 37 Abstract book

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ESTRO 37

radio-chemotherapy 75.2%, sequential 24.8%. Radiation DBE 70.1-88.8 (median 83.05). Acute toxicity present in 92.4%. Median follow up of 32 months (1.97-151 months), At time of analysis 82.7% of patients were dead ( 66% died from cancer, 16.7% died from other causes). Median OS 21.9 months and DFS 15.2 months. OS 2 years: 44.6%, 5 years 23.2%, 10 years 10.4%. DFS 2 years: 31.2%, 5 years 21.9%, 10 years 15.2% Independent prognostic factors for OS were: Weight loss >5% (p=0.003), age >70 years (p=0.03) and stage (p=0.004), and for DFS: Stage(p=0.03), Weight loss >5%(p=0.03) and PTV>600 cc (p=0.04). Patients with SCS>8 had more probability of dying from a non-cancer cause than those with lower morbidity (p: 0.02)

localized stages (not candidates for surgery or SBRT) or locally advanced as sequential treatment after chemotherapy with good response in patients non candidates for concomitant radio-chemotherapy. Technique: 3D planning. Image control by portal image on a weekly basis. GTV: macroscopic primary tumour and lymph nodes> 1 cm or PET positive. CTV: GTV + margin of 6 mm in all directions. PTV: CTV + 10 -15mm. Patient criteria: ECOG 0-2 (ECOG 0-1 if> 75 years). Weight loss <10%. No serious comorbidities. Retrospective analysis of toxicity reported RTOG scale. Comorbidity simplified score scale (SCS). Kaplan-Meier and Chi-square tests were used. Results From March 2014 to march 2016, 46 patients were treated. Median age 74 years (49-84), <70 years (34.8%), >=70 years (65.2%). 43 men, 3 women. SCS <=7: 69%, >7: 31%. ECOG 0: 24%, ECOG1: 54%, ECOG2: 22%. Small-cell lung cancer 17.4%, NSCLC 82.6%. Stages IB-IV. Sequential 63%, Exclusive RT 37%. Acute toxicity 74%. Acute respiratory toxicity G0: 87%, G1:8.7%, G2: 4.3%, Acute Digestive toxicity, G0: 32.6%, G1: 45.7%, G2:19.6%, G3: 2.2%. Acute asthenia G0: 76%, G1:17.4%, G2: 6.5%. Median follow-up 14.3 months. 63% patients relapsed, 43.5% alive, 22 patients died from cancer, 4 died from non-tumour cause. 1 year OS: 64%, 2 years OS: 38%. 1 year DFS:45.9%, 2 year DFS:28%. No differences were seen in global toxicity regarding age (p=0.4) or SCS (p=0.32). No differences were seen in toxicity greater than G1 regarding age (p=0.3) or SCS (p=0.97).

Conclusion Age, Haemoglobin, weight loss, stage and PTV volume were factors with significant poor outcome in our series. Age >70 years was associated with more comorbidities. Despite OS was the same independently the SCS score, the group of SCS >8 had more probability of dying from non-tumoral causes. EP-1377 Tolerability of radical lung hypofractionated radiotherapy in elderly patients A.M. Otero Romero 1 , I. Navarro-Domenech 1 , A. Fernández-Forné 1 , A. Román-Jobacho 1 , R. Correa- Generoso 1 , M. García-Anaya 1 , I. García Ríos 1 , R. Ordoñez- Marmolejo 1 , J. Gómez-Millán 1 , A. Pérez-Rozos 1 , J. Medina-Carmona 1 1 Virgen de la Victoria, Oncología Radioterápica, Málaga, Spain Purpose or Objective To analyse the influence of age and comorbidity in toxicity, overall survival (OS) and disease free survival (DFS) of hypofractionated radiotherapy (RT) in lung cancer. Material and Methods In our institution we have adopt the hypofractionated scheme of 55 Gy in 20 fractions (2.75 Gy per fraction) for

Conclusion •

In our experience hypofractionated radiation therapy in lung cancer with 3D technique has a good tolerance and is a safe treatment for elderly patients or with comorbidity in patients with ECOG<=2. No differences in acute toxicity, OS or DFS were seen depending on age or SCS. - This hypofractionated scheme provides the advantage of shortening the treatment to 4 weeks rather tan 6 weeks compared to conventional fractionation. A longer follow-up is required to have evidence of chronic toxicity and clinical outcomes.

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