1. Stereotactic Body Radiation Therapy (SBRT): The optimal indication for operable tumors in inoperable patients D.Katsochi 1, S.Kosmidis 1, A.Fotopoulou 1, G.Kollias 2, C.Paraskevopoulou 2 Introduction Material & Method ResultsConclusion 1 Radiation Oncologist, Radiation Oncology Center, Diagnostic and Therapeutic Center of Athens “HYGEIA”, Athens, Greece 2 Medical Physicist, Medical Physics Department, Radiation Oncology Center, Diagnostic and Therapeutic Center of Athens “HYGEIA”, Athens, Greece Stereotactic body radiation therapy is a highly conformal treatment, compared to conventional radiation therapy that delivers very high doses of radiation to the tumour target in a small number of fractions. SBRT has emerged as non invasive alternative to surgery for early stage NSCLC. Preliminary data of Clinical experience in Radiation Oncology Department of DTCA HYGEIA. Between May 2009 and July 2014, 48 patients with pulmonary tumors, medically inoperable, were treated with SBRT (Elekta Axesse) using daily image guidance (cone beam CT, Hexapod) for patient positioning and target localization. Computed tomography (CT scan) and PET computed tomography (FDG/PET) were used for target delineation and planning. Median prescription dose was 36 Gy in 3 fractions in 28 patients or 30Gy in 5 fractions for 20 patients with poor pulmonary function. All patients completed treatment. Median follow up was 13 months (range 2- 20). All patients achieved disease local control, 36 patients with complete tumor regression and 12 patients with minimal residual tumor with no progressive disease at follow up. None patient presented blood toxicity or pulmonary toxicity (pneumonitis) except for two patients who were treated with corticosteroids. Image guided SBRT in selected patients is a feasible, safe, and effective treatment for medically inoperable early stage lung cancer. VMAT Volumetric Modulated Arc TherapyFollow up CT 3 and 6 months after SBRT

2. Early Tumor Response with Image Guided Concomitant Boost Radiotherapy Technique D.Katsochi 1, S.Kosmidis 1, A.Fotopoulou 1, G.Kollias 2, C.Paraskevopoulou 2 Introduction Material & Method Results Conclusion 1 Radiation Oncologist, Radiation Oncology Center, Diagnostic and Therapeutic Center of Athens “HYGEIA”, Athens, Greece 2 Medical Physicist, Medical Physics Department, Radiation Oncology Center, Diagnostic and Therapeutic Center of Athens “HYGEIA”, Athens, Greece One of the main objectives in patients with advanced unresectable head and neck, lung, cervical and brain carcinoma is to improve local control of tumor disease. The introduction of image guided radiotherapy offers the opportunity to safely apply a supplementary dose to the macroscopic disease. This accelerated radiotherapy course, known as concomitant boost, has the advantage of increasing the total dose delivered and tumor response without increasing the number of fractions. From May 2009 to July 2014, 168 patients were treated with concomitant boost technique. The distribution of primary tumors was 79 patients with lung cancer, 54 patients with head and neck cancer, 22 patients with brain tumors and 13 patients with cervical cancer. 144 patients received chemotherapy during radiation therapy. Patients were treated using the 3D Conformal or VMAT technique with Synergy Elekta and/or Elekta Axesse machine. Planning target volume (PTV) was treated daily with 1.8 Gy for 5 to 6 weeks to a total dose of 45-60 Gy, while the dose to the Gross Tumor Volume (GTV) was boosted up to 55-70 Gy depending on the anatomic region. Organs at risk were irradiated to safe limits. In 76% of the patients we readapted the treatment plan due to local tumor regression using image guidance data (CBCT). All patients completed the treatment plan with no major toxicity. Follow up was scheduled at the end of the treatment, three and nine months after. All patients achieved local tumor control, 101 patients (60%) with complete tumor response, 52 patients (31%) with partial response and 15 (9%) with stable disease. Concomitant boost in combination with Image Guided Radiotherapy is a feasible, safe and effective treatment for patients with unresectable carcinomas. Results are encouraging and promising regarding locoregional disease control. Brain tumor MRI and CT images fused. Delineation of GTV (tumor), CTV (edema), PTV planning tumor volume. Concomitant boost to GTV. Cervical Cancer patient treated with concomitant boost technique: Follow up in 2 and 5 months after treatment. Complete response. Lung cancer. Delineation of GTV (tumor) and PTV. Concomitant boost to GTV. Follow up CBCT shows tumor early response. Dose painting to the hypermetabolic part of the laryngeal tumor.