ESTRO 37 Abstract book

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ESTRO 37

as a predictive factor for occurrence of late endocrine effects after radiotherapy in multivariate analysis. Conclusion Late endocrine effects after radiotherapy of nasopharyngeal carcinoma are frequent and require systematic screening to begin adequate treatment earlier. Only gender has been identified as predictive factor in multivariate analysis in this study. EP-1140 Hypofractionated radiotherapy for early glottic cancer: retrospective analysis of single institution J.W. Lee 1 , J.E. Lee 2 , J.H. Sohn 3 , D. Ahn 3 1 Kyungpook National University Hospital, Radiation Oncology, Daegu, Korea Republic of 2 Kyungpook National University School of Medicine, Radiation Oncology, Daegu, Korea Republic of 3 Kyungpook National University School of Medicine, Otorhinolaryngology-Head and Neck Surgery, Daegu, Korea Republic of Purpose or Objective This study evaluates the results of hypofractionated radiotherapy (RT) for early glottic cancer. Clinical and dosimetric outcomes were analyzed. Material and Methods We analyzed 87 patients with cT1-2N0M0 squamous cell carcinoma of glottis who treated with hypofractionated RT between January 2011 and December 2016. Radiotherapy was given at 60.75Gy in 27 fractions except 2 patients who received 63Gy in 28 fractions. Forty three patients received simultaneous integrated boost (SIB) consisted of 2.3 to 2.5Gy per fraction. Sixty seven patients were treated with Intensity-modulated radiotherapy (IMRT) and 20 patients were treated with 3D conformal RT (CRT). The median follow-up duration was 30.7 months (range, 5.5 to 76.5 months). The primary end point was locoregional disease-free survival (DFS). The secondary end points were cancer-specific survival (CSS), toxicities of hypofractionated RT. Each end-point was measured from the end of the RT. Carotid artery (CA) dose was evaluated in dose-volume histogram by each RT technique (IMRT vs. 3D CRT). Results All patients achieve complete remission after median 49 days from the end of RT (range, 14 to 206 days). The 5- year DFS was 88.7% and 5-year CSS was 96.9%. T2 stage was prognostic factor for local recurrence-free survival after radiotherapy ( p =0.006). No one had grade 3 or higher acute and chronic toxicities. IMRT significantly lowered carotid artery dose than did 3D CRT (V35, 24.7% vs. 55.8%, p <0.001; V50, 6.8% vs. 43.1%, p <0.001). Conclusion Hypofractionated RT achieved high locoregional disease control rate and cancer-specific survival rate. Fraction size of 2.25Gy provided good local control regardless of the use of SIB dose with 2.5Gy. IMRT may be possible to reduce toxicity compared with 3D CRT. EP-1141 Treatment outcomes of olfactory neuroblastoma: two institutional study J.H. Chung 1 , I.A. Kim 2 , J.S. Kim 2 , H.G. Wu 1 , K.Y. Eom 2 1 Seoul National University Hospital, Department of Radiation Oncology, Seoul, Korea Republic of 2 Seoul National University Bundang Hospital, Department of Radiation Oncology, Seongnam-si-, Korea Republic of Purpose or Objective We aimed to analyze oncologic outcomes and assess the impact of clinic-pathologic factors on survival outcomes. Material and Methods In this retrospective study, 77 histologically confirmed olfactory neuroblastoma (ONB) patients were accrued from Seoul National University Hospital and Seoul National University Bundang Hospital between Jan 1999

Purpose or Objective Oral mucositis (OM) is a common limiting side effect encountered in head and neck cancer (HNC) patients, treated by chemoradiotherapy (CRT). Supportive cares like low-level laser therapy (LLLT) could reduce OM A randomised phase III trial was conducted in HNC patients (oral cavity, oro/hypopharyngeal cancers, stage III or IV) treated by conformational radiotherapy (3D or intensity modulated radiation therapy) combined with chemotherapy (cisplatin or carboplatin, 5-fluorouracil, or cetuximab). Patients were randomised (1:1) and treated by lasertherapy on OM lesions grade ≥ 2 (curative dose of 4 J/cm2 or placebo), until recovery. Clinical examination of the oral cavity was performed weekly and blindly. Severity of OM (incidence and duration of grades ≥ 3) was used as primary end point. Results Among 97 randomised patients, only 83 (85.6%) could be assessed at the end of cancer treatment (patients erroneously included and early CRT interruptions). Randomisation and population characteristics (sex ratio, age, radiochemotherapy procedures, toxicities incidence) were still comparable between the two LLLT groups. An acute OM (grade ≥ 3) was observed in 41 patients (49.4%): 23 patients (54.8%) of the active LLLT group versus 18 (43.9%) in the control group (modified intend to treat, p=0.32). Median time before occurrence of OM ≥ grade 3 in half of the patients was 8 weeks in active LLLT group (vs. 9 weeks in control group). For OM grade ≥ 2, 68 patients (81.9%) were concerned, with a delay of 5 weeks (active arm) vs. 6 weeks. Among 83 patients, 32 patients had no LLLT (active or sham) because of unreachable OM lesions. Per protocol analysis showed that 70.6% of patients developed OM grade ≥ 3 (p=0.75). 95% of patients exhibited a very good tolerance of LLLT. Conclusion This study assessed LLLT according to the Multinational Association of Supportive care in Cancer recommenddations (4J/cm2), but lacked power. LLLT seems to be well tolerated with a good safety profile. EP-1139 Late endocrine effects after radiotherapy of nasopharyngeal carcinoma N. Bouzid 1 , I. Barka 2 , M. Zaouali 3 , K. Ach 2 , N. Bouaouina 1 1 Farhat Hached Hospital, Department of radiation oncology, Sousse, Tunisia 2 Farhat Hached Hospital, Department of endocrinology, Sousse, Tunisia 3 Farhat Hached Hospital, Department of physiology, Sousse, Tunisia Purpose or Objective To study the late endocrine toxicities in nasopharyngeal carcinoma (NPC) patients who achieved long-term survival after radiotherapy and analyze the predictive factors. Material and Methods Fifty five NPC patients treated with radiotherapy at our centre were retrospectively analyzed. All patients had a static and / or dynamic hormonal exploration in the department of endocrinology, Farhat Hached Hospital between February and October 2015. Results Late endocrine toxicities were detected in 83, 6% of cases. A pituitary dysfunction was noted in 83, 6%, peripheral in 3, 63% of cases and central in 18, 18% of cases. A Growth hormone deficiency was detected in 67, 27% of cases, an adrenocorticotopic hormone deficiency was found in 25,45% of cases, a gonadotropin deficiency was noted in 20% of cases and an hypothyroidism was detected in 16,36% of cases. Only male gender was found incidence and severity. Material and Methods