ESTRO 37 Abstract book

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ESTRO 37

was nausea (n=10). Two patients were hospitalized during treatment for coughing and faintness. Among four patients with initial facial paralysis, two had an improvement. On four patients with initial tinnitus, two patients had a decrease in their symptoms and two patients sustained stabilization. No aggravation of initial symptoms has been reported. Conclusion IMRT is a well-tolerated treatment modality of skull base paragangliomas with documented functional benefit. However, a longer follow-up is necessary in order to assess local control, and to detect the onset of late side effects and secondary malignancies. EP-1175 Role of Radiotherapy in the management of metastases from salivary gland carcinoma. C. Franzese 1 , S. Tomatis 1 , P. Bossi 2 , P. Franco 3 , P. Bonomo 4 , G. Beltramo 5 , I. Bossi Zanetti 5 , D. Cante 6 , A. Argenone 7 , D. Musio 8 , C. Furlan 9 , M. Scorsetti 1 , C. Fallai 10 , E. Orlandi 10 1 Humanitas Clinical and Research Hospital, Radiotherapy and Radiosurgery, Rozzano Milan, Italy 2 Fondazione IRCCS Istituto Nazionale Tumori, Head and Neck Medical Oncology, Milan, Italy 3 AOU "Città della Salute e della Scienza" Università degli Studi di Torino - Sede Molinette, Radiotherapy Department, Turin, Italy 4 Azienda Ospedaliero-Universitaria di Careggi presso Policlinico Careggi, Radiotherapy department, Florence, Italy 5 Ciberknife- Centro Diagnostico Italiano, Radiotherapy Department, Milan, Italy 6 Ospedale Civile ASL TO4, Radiotherapy Department, Ivrea, Italy 7 Istituto Nazionale per lo studio e la cura dei Tumori - Fondazione "G. Pascale", Radiotherapy Department, Naples, Italy 8 Università La Sapienza - Policlinico Umberto I, Ist. di Radiologia, Rome, Italy 9 Istituto Nazionale Tumori- Centro di Riferimento Oncologico, Radiotherapy Oncology Department, Aviano, Italy 10 Fondazione IRCCS Istituto Nazionale Tumori, Radiotherapy Oncology Department, Milan, Italy Purpose or Objective Salivary gland carcinomas (SGC) are rare malignancies comprising about 5% of head and neck cancers. At least 24 different histological types of SGC exist, with different metastatic potential. The presence of distant metastases is one of the strongest predictor of survival and treatment strategies are limited. The purpose of this study was to investigate the outcome of patients treated with radiotherapy (RT) on metastatic sites derived from SGC. Material and Methods We conducted a retrospective multicenter analysis of all the patients treated with RT on SGC metastases from 2006 to 2016 in 9 Italian tertiary cancer centers. Analysis was conducted on behalf of Italian Association of Radiation Oncology (AIRO) Head and Neck Working Group. Clinical factors, disease characteristics and treatment outcomes were evaluated. Univariate and multivariate analyses were performed to identify factors associated to local control of the metastatic lesion (LCM) and overall survival (OS). Tumour response was classified as stable disease (SD), partial response (PR) or complete response (CR) based on radiological images for visceral metastases or clinical assessment for bone symptomatic lesions. Results A total of 64 patients was included in the present analysis. Forty-four (68.7%) patients were male; 10 (15.6%) patients were diagnosed with synchronous metastases. Median time to metastasis was 1.4 years (range 0 – 24 years). Median age was 56.5 years (range 25

– 82 years). Most frequent histologic type was adenoid cystic carcinoma (ACC), observed in 56.2% of the cases. The majority of patients (53, 82.8%) was treated with advanced RT technique (including IMRT, VMAT and SBRT) and median BED10 was 54.1 Gy (range 14.4 – 151 .2 Gy). Forty-eight (75%) patients were treated on a single metastasis. Median follow-up was 3.6 years (range 1.8 – 25.6 years). Overall, clinical and/or radiological benefit from RT was achieved in 56 patients with CR in 18 patients and PR in 18 patients. Rates of LCM at 3-, 5- and 10- years were 64.0%, 47.6% and 21.9%. RT technique and time to metastasis were all impacting on LCM both at univariate and multivariable analysis, with advanced RT technique (HR = 0.26, p=0.013) and longer time to metastasis (HR = 0.97, p=0.001) being protective factors. Rates of OS at 3-, 5-, and 10- years were 82.9%, 77.8% and 70.6%. At multivariable analysis histology (HR = 0.13, p=0.042), time to metastasis (HR = 0.86, p=0.014) and RT technique (HR = 0.049, p=0.011) retained statistical significance. Conclusion In selected cases, RT is an effective treatment for metastatic SGC, achieving long-term disease control. The highest benefit was obtained in patients affected with ACC, particularly in those with a longer interval to the development of metastasis and in those treated with advanced RT techniques. Prospective trials are needed to better identify the subset of patients with a potential benefit from RT and to define its integration with systemic therapies. EP-1176 Long-term outcomes and toxicity profile of chemoradiation for nasopharyngeal carcinoma. E. Netto 1 , M. Ferreira 2 , S. Esteves 3 , I. Sargento 2 , M.T. Alexandre 2 , R. Pocinho 4 , A. Mota 4 , M. Labareda 4 , M. Rito 5 , J. Cabeçadas 6 , R. Pacheco 7 , M. Magalhães 7 , M. Roldão 4 1 NOVA Medical School, Radiation Oncology, Lisboa, Portugal 2 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Medical Oncology, Lisboa, Portugal 3 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Clinical Research Unit, Lisboa, Portugal 4 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Radiation Oncology, Lisboa, Portugal 5 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Pathology, Lisboa, Portugal 6 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Pathology Department, Lisboa, Portugal 7 Instituto Português de Oncologia de Lisboa Francisco Gentil- EPE, Otorhinolaryngology, Lisboa, Portugal Purpose or Objective Report our matured clinical data of combined modality treatment and toxicity profile for nasopharyngeal carcinoma in a non-Endemic European cohort of patients. Material and Methods We found 109 patients with biopsy-proven naso- pharyngeal carcinoma treated between Feb/09 and Dec/13. All patients received intensity modulated radiotherapy (IMRT) similarly to the described in RTOG 0615, with 69,96Gy in 33 daily fractions to the primary and nodal GTVs, 59,4Gy to the areas at risk and 54Gy to the uninvolved lower neck. Concurrent and adjuvant platin-based chemotherapy was delivered similarly the to Intergroup 0099 trial. Survival was estimated with Kaplan-Meier survival analysis, log-rank test was used to detect differences and a multivariate analysis of variables was performed (SPSS v.21, IBM). Results Patients had median age of 53 years; 97% caucasian; 74% male; 72% WHO grade III; 43% T1; 14% T2; 18% T3, 25% T4; 17% N0; 17% N1; 39% N2; 27% N3. With a median follow up of 46 months, the 4-yr local control was 90,2% (88,6% for T1; 100% for T2; 85% for T3; and 91,7% for T4), distant mestastases-free survival was 86% and a overall