ESTRO 36 Abstract Book

S738 ESTRO 36 2017 _______________________________________________________________________________________________

bone/soft-tissue/lymph-nodes was 46% (median survival time, 11 months), while that was 15% for the patients who received PRIT to other organs (median survival time, 4 months). Conclusion With regard to patients with good performance status, prognosis of patients who received PIRT to bone/soft- tissue or lymph-nodes was comparatively good. Despite small patient number of this study, it seemed that extremely hypofractionated PIRT was not suitable for these patients. EP-1395 CyberKnife treatment of intraorbital metastases: a single center experience on 24 lesions. G. Riva 1 , M. Augugliaro 1 , G. Piperno 1 , A. Ferrari 1 , E. Rondi 1 , S. Vigorito 1 , R. Orecchia 1 , B.A. Jereczek-Fossa 1 1 Istituto Europeo di Oncologia - IEO, Radiotherapy, MIlan, Italy Purpose or Objective The aim of the study is to evaluate the feasibility, acute toxicity and symptoms control of CyberKnife (Accuray, Sunnyvale, CA)-based stereotactic radiotherapy (CBK-SRT) on intraorbital metastases. Material and Methods This retrospective analysis included patients (pts) with symptomatic metastases located wholly within the orbit. Palliative radiation treatment was performed using CyberKnife image-guided technology (using skull-tracking technique). Gross tumor volume (GTV) volume was defined on a pre-radiotherapy magnetic resonance imaging (MRI) with Gadolinium. Treated volumes and dose-volume histograms (DVHs) are discussed. Acute toxicity was recorded according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) Scale. Results Between April 2012 and July 2016, 24 metastases (21 pts, 3 treated bilaterally) underwent CBK-SRT for intraorbital lesions (10 intraocular, 14 periocular) from different primary tumors (breast in 13 pts, lung in 3 pts, kidney in 2 pts, lymphoma in 1 pts, thyroid in 1 pts, trunk leiomyosarcoma in 1 pts). The median treatment dose was 18 Gy (range, 15-24 Gy) given over a median of 3 fractions (range, 2-3 fractions) with a median dose of 6 Gy per fraction (range, 5-10 Gy/fraction). Treated volumes and DVHs are reported in Table 1. At the end of the treatment, grade 1 toxicity according to RTOG/EORTC score was observed in 8 cases. No change in visual field or loss of vision was documented. 13 lesions of 24 had undergone post-radiotherapy MRI and after median follow-up of 6 months (range, 2.0-26.5 months) no local recurrence occurred. All of these patients reported decreasing pre-radiotherapy symptoms and improvement in quality of life. Longer follow-up (more than 12 months) is available in 4 lesions with complete radiological response in all cases.

Conclusion In our experience, CyberKnife radiotherapy is a well- tolerated, safe and efficacious technique for palliative treatment of intraocular and periocular metastases. EP-1396 Versatis® and focal neuropathic pain in cancer patients (screening tool) C. Prieto Prieto 1 , E. López Ramirez 2 1 Hospital Universitario Virgen de las Nieves, Radiation Oncology, Granada, Spain 2 Oncosur, Oncología Radioterápica, Granada, Spain Purpose or Objective Lidocaine 5% patch (L5%P) = (Versatis®) represents a novel therapeutic approach to neuropathic pain in cancer patients. The objective of this study is to evaluate its role in treating acute or chronic focal neuropathic pain (FNP) in cancer patients, regardless of its causal relationship with the tumour. Material and Methods We collected information from 33 cancer patients with focal neuropathic pain (FNP) treated with L5%P. Some interesting data related to L5%P use were analyzed: NP nature, body areas affected, previous and concomitant analgesic treatment, time from patch application to analgesic effect, duration of therapy with L5%P, analgesic efficacy and adverse reactions. Therapeutic indication with L5%P was established in all patients using a validated FNP screening tool (ST) consisting in 4 simple questions. Results All patients underwent radiotherapy in our Departments. 66.7% of them (n=22) suffered from FNP related with cancer and its therapies. In the other 33.3% of cases (n=11), FNP was not considered related. Potent analgesic effect of L5%P was observed in 23 cases (69.7%), and partial effect in 5 cases (15,2%). It represents an 84.9% of efficacy in our sample. 81.3% of patients did not report adverse reactions at all. 45.5% of patients achieved pain control within one week after starting L5%P treatment. 39.4% of patients did not need concomitant analgesic

treatment. Conclusion