ESTRO 36 Abstract Book

S589 ESTRO 36 2017 _______________________________________________________________________________________________

Dosimetric information, medical records and tumor characteristics of 49 patients were collected. CT, structure set and dose files were available for 32 patients, making it possible to perform deformable image and dose registration to allow plan summation and extract precise cumulative dose statistics for the CA. For the remaining 17 patients a reliable approximation of the cumulative dose to the CAs was made by comparing printed CT-slices with isodose curves from the previous RT courses with the dose distribution from the reirradiation. Corresponding EQD2 was calculated with an α/β-ratio=3. Results Forty-four patients had received 1 prior RT course, while 5 had received 2 prior RT courses. Ten patients received reirradiation with proton RT and 39 with carbon ion RT (CIRT). In the 49 patients a total of 74 CAs had been reirradiated to a median cumulative Dmax EQD2 of 106 Gy (RBE) (range: 25-167 Gy (RBE)). Details are presented in TABLE 1 and FIGURE 1 . Median time between 1 st and final RT was 29 months (range: 3-205 months). Median time of follow-up was 10 months (range: 1-41 months). Two patients (4%) experienced profuse oronasal bleeding at 6 and 8 months after reirradiation, both fatal. Cumulative Dmax EQD2 for these patients CAs were 130 and 107 Gy (RBE), respectively. Both had recurrent tumors completely surrounding the CA. The first patient had undergone surgery close to the CA prior to the reirradiation. At the time of bleeding he performed a CT-angiogra phy revealing a pseudoaneurysm on the CA, making the diagnosis of CBS highly probable. The second patient had a recurrent tumor at the site of bleeding. Autopsy was refused, making it impossible to ascertain if the bleeding was due to CBS or from pathological tumor vessels. If we attribute both cases to CBS, the CBS-rate for reirradiated CAs was 2.7% (95% CI 1.0-6.4%).

Conclusion Reirradiation in the H&N region with particle therapy gives CBS-rates comparable to normo- or hyperfractionated photon RT, and does not seem to increase in hypofractionated schedules typically used in CIRT, in contrast to what is reported in hypofractionated SBRT with photons. The low number of events does not make it possible to define significant risk factors or tolerance doses for the CA. EP-1080 Psychological distress in patients with head and neck cancer during radiotherapy M. Massaccesi 1 , L. Dinapoli 1 , A. Pesce 1 , R. Autorino 1 , A. Tenore 1 , M. Balducci 1 , D. Smaniotto 1 , G. Chiloiro 1 , M. Rigante 2 , G. Cadoni 2 , G. Paludetti 2 , V. Valentini 1 , F. Miccichè 1 1 Università Cattolica del Sacro Cuore -Fondazione Policlinico A. Gemelli, Radiation Oncology Department- Gemelli ART, Rome, Italy 2 Università Cattolica del Sacro Cuore -Fondazione Policlinico A. Gemelli, Institute of Otorhinolaryngology, Rome, Italy Purpose or Objective The treatment of patients with head and neck (H&N) cancer is usually complex and burdensome. Radical radiotherapy (RT), which may follow surgery and be combined with chemotherapy, usually lasts 6 to 7 weeks and more than half patients can experience relevant acute toxicity. Therefore the experience of receiving RT can be both stressful and anxiety provoking. Aim of this study was to evaluate the psychological distress of patients with H&N cancer during RT. Material and Methods Consecutive patients with H&N cancer who underwent RT with radical intent between January and September 2016 were included in this analysis. Psychological support was available for all patients and Distress Thermometer (DT) and Hospital Anxiety and Depression Scale (HADS) were administered to evaluate emotional distress and mood, respectively at the beginning (T0), after three-four weeks (T1), and at the end (T2) of the RT course. Toxicity was evaluated weekly by CTCAE version 4.0 criteria.