ESTRO 36 Abstract Book

S659 ESTRO 36 _______________________________________________________________________________________________

Results After a median interval of 11.5 months, 17 patients (31%) relapsed locally or regionally: six within the initial primary tumour volume, five within the initially affected lymph nodes, three metachronously within primary tumour and initially affected lymph nodes, and three both inside and outside of the initial nodal disease. All sites of loco- regional recurrence had received 92%-106% of the prescribed dose. Thirty-seven patients (69%) developed distant metastases (37.8% liver, 35% brain). Among all investigated co-factors only total GTV revealed a significant correlation with patient outcome. Conclusion In our study most recurrences occurred in the initial primary tumour or lymph node volume, or distantly. We did not register any case of isolated nodal failure, suggesting the use of selective nodal irradiation, possibly with the addition of supraclavicular irradiation in patients with affected lymph nodes in the upper mediastinum, instead of ENI. Among all investigated patient- and tumour-related co- factors only total GTV revealed a significant correlation with patient outcome. Further prospective clinical trials are needed for final determination of optimal irradiation fields in SCLC patients. EP-1221 Adherence to lung cancer guidelines and its impact on survival I. Linares 1 , M. Sánchez 2 , J. Pérez-Alija 3 , E. Molina 2 , Y. Chang-Chan 4 , R. Guerrero 5 , J. Expósito 5 1 Institut català d´Oncologia ICO- L'Hospitalet de Llobregat, Radiation Oncology, Barcelona, Spain 2 Escuela Andaluza de Salud Pública. Instituto de Investigación Biosanitaria ibs. Hospitales Universitarios de Granada/Universidad de Granada CIBER de Epidemiología y Salud Pública CIBERESP, Escuela Andaluza de Salud Pública, Granada, Spain 3 Hospital Plató, Radiation Oncology, Barcelona, Spain 4 Escuela Andaluza de Salud Pública. Instituto de Investigación Biosanitaria ibs. GRANADA. Hospitales Universitarios de Granada/Universidad de Granada, Escuela Andaluza de Salud Pública, Granada, Spain 5 Complejo Hospitalario Universitario de Granada, Radiation Oncology, Granada, Spain Purpose or Objective Clinical practice guidelines are tools to improve quality and reduce variability of cancer care. Our objective is to evaluate the concordance between lung cancer guidelines and clinical practice in Granada and its impact on survival. Material and Methods Data were obtained from the population-based cancer registry in Granada (Spain). All cases of newly diagnosed primary lung cancer (non-small-cell lung cancer a small cell lung cancer) in 2011-2012 were included. To describe the adherence to guidelines, 10 indicators regarding diagnostic and treatment were identified. The indicators were assigned according to the pathology, stage and ECOG performance status. For those patients who did not adhere to the indicators, the medical record was reviewed to determine the reason for this. One and two-year relative survival was compared between patients treated according to clinical guide recommendations and those who were treated otherwise. Results 685 patients were enrolled; 490 were discussed at a multidisciplinary team meeting. Microscopic verification was available in 81%. 58.6% did not received guideline recommended diagnosis and treatment. Most common non-adherence reasons were a bad performance status and advanced age (16.3%), exitus (8.8%) and patient preference (2.8%). Better adherence was shown in early

stage (62.1% stage I and 66.7% stage II versus 57% stage IV) and women (68.3% versus 44.8% in men). Patients who received guideline recommended diagnosis and treatment had improved survival compared with those who did not: one and two-year relative survival of 51% and 28.2% versus 34.1% and 17.5%. Conclusion Guidelines adherence monitoring can be useful to reduce variability in cancer care. A significant proportion of cases of non-adherence to guidelines are due to unavoidable causes. Alternative guidelines are needed for those cases. Acting in accordance to guidelines improves survival. EP-1222 Beclin-1 expression of circulating tumor cells in non-small cell lung cancer patients. C. Prieto Prieto 1 , D. De Miguel 2 1 Hospital Universitario Virgen de las Nieves, Radiation Oncology, Granada, Spain 2 GENYO. Centre for Genomics and Oncological Research, Pfizer/University of Granada/Andalusian Regional Government-, Granada, Spain Purpose or Objective Non-small cell lung cancer (NSCLC) accounts for 75-80% of the total lung cancer cases, including those at advanced stages IIIA and IIIB, where chemotherapy and radiotherapy are the main recommended treatments. Despite this, recurrence and progression are still present, largely caused by the release of circulating tumor cells (CTCs) into peripheral blood, where they travel up to a secondary organ to establish metastasis. Autophagy is an auto- proteolitic mechanism by which eukaryotic cells can surround intracellular components into vesicles like lysosomes. Beclin-1, whose expression has never been described in CTCs, is plays a critical role in the regulation of autophagy. In spite of this, its role as a risk factor for radiotherapy resistant is not clear yet. Our objective was to identify the prognostic value of the presence of CTCs, from peripheral blood of NSCLC patients undergoing concomitant radiotherapy and chemotherapy treatment, and their characterization with Beclin-1. Material and Methods This prospective and ongoing study included 21 NSCLC patients from Virgen de las Nieves Hospital (Granada, Spain), who have a locally advanced and unresectable disease (stages: inoperable IIIA, IIIB and IV) and were treated with concomitant radiotherapy (total dose of 60Gy with standard fractionation) and chemotherapy (Cisplatin- Vinorelbine mostly). Follow-up was performed by computed tomography (CT) for 3 months after the treatment, however Positron Emission Tomography (PET) was performed in some of them. According to our immunomagnetic selection methodology, CTCs were isolated by epithelial markers from peripheral blood samples before the treatment, and 3, 8 and 48 weeks after and characterized for Beclin-1 expression by immunofluorescence. Results Even though the low number of patients, our results revealed a tendency or an association between presence of CTCs at baseline status with; tumor response observed by CT and PET ( p =0.99), tumor stage ( p =0.036) and local and distant progression ( p =0.088). On the other hand, 19% of the patients showed CTCs BECLIN1+ but it was not associated with any clinicopathological variables as progression or mortality. Conclusion In conclusion, the presence of CTCs before treatment may be a predictive factor for progression in NSCLC patients, but Beclin-1 may not, however more patients are needed to reach statistical significance.