Abstract Book

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ESTRO 37

Conclusion The use of IMRT technique and the prevention of acute toxicities especially oral mucositis are required to significantly reduce the weight loss during radiotherapy for nasopharyngeal carcinoma. Long-term follow-up of our patients is needed to determine the impact of weight loss on the prognosis of the disease. EP-1161 The importance of neck nodal metastasis and elective nodal irradiation in esthesioneuroblastoma C. Yung Chih 1 , C.E. Hsieh 1 1 Chang Gung Memorial Hospital, Radiation oncologist, Taoyuan, Taiwan Purpose or Objective To evaluate the importance of cervical nodal metastasis and elective nodal irradiation in patients with This retrospective study analyzed 39 patients with ENB which treated at Chang gung memorial hospital between 2000 and 2014. The cancer-specific survival, regional recurrence, and distant metastasis were compared using the Kaplan–Meier method and log-rank statistics. Results Thirty-nine patients (12 male; 27 female) were analyzed. Median age was 49.3 years (range 6.1-89.2). Median follow up was 8.58 years. Twenty-eight patients (71.8%) had T3 or T4 disease at presentation. By modified Kadish stage: 10 patients (25.6%) were stage A or B, 22 patients (56.4%) were stage C, and seven patients (17.9%) were stage D. Those with distant metastasis were excluded from this study. Eighty-five percent of patients received surgical resection as primary treatment, and 64.1% received postoperative radiation or chemoradiation. Overall and disease-specific survival for all patients was 69.5% and 79.3% at five years. Neck nodal metastasis was associated with inferior overall survival (p=0.035) and distant free survival (p=0.015). Among 17 patients with neck nodal metastasis, six patients developed distant metastasis. Only one patient developed distant metastasis in 22 patients without cervical LN metastasis. The neck metastatic lymph node number more than four is correlated with distant metastasis. Seven patients received elective nodal irradiation with 100% regional control.Nodal metastases developed in 10 out of 25 patients without ENI at a median time of 36.4 months. Elective nodal irradiation had trend to improve regional control (p=0.073) and disease-specific survival (p=0.091). Kadis h stage T stag e Treatment esthesioneuroblastoma. Material and Methods

had regional nodes and 2 (9.5%) patients had distant metastatic disease. 15 (78.9%) underwent surgical resection and 12 of those had ART using 60Gy in 30 fractions. Only 2 (16.7%) developed a local recurrence following ART, however 7 (58.3%) patients subsequently developed distant metastatic disease. The median time to the development of metastasis was 5.1 months (range 3.1-36.6). Of the 6 patients who received Palliative RT, 5 (83.3%) had a good symptomatic and clinical response. 12 (57.1%) patients either presented with metastatic disease or subsequently developed it. Of these, 8 (66.7%) patients received 9 courses of systemic therapy (Pembrolizumab=5, Dacarbazine=3 and Ipilimumab=1). 2/5 patients treated with pembrolizumab responded both with a complete radiological response. No responses were observed with the other drugs. 3 patients had c-kit mutational analysis performed all were wildtype. At the time of this analysis 10 patients had died with a median survival of 10.7 months (2.5-70.3). Conclusion The incidence of nasal cavity melanoma is higher than expected in our centre with approximately 1 patient diagnosed annually per million in our region. Surgery followed by adjuvant RT provides good local control, however the majority of patients developed disseminated disease despite radical treatment of the primary site. Palliative RT is an effective treatment and leads to a good clinical response with symptom control. Favourable outcomes for metastatic disease were seen in patients receiving pembrolizumab. Further collaborative research is required to better understand this rare disease and to identify better treatment approaches particularly for those with advanced disease. EP-1160 Predictive factors of weight loss during radiotherapy for nasopharyngeal carcinoma F. Nejla 1 , F. Zied 1 , M. Wafa 1 , C. Ines 1 , G. Abdelmonem 2 , F. Mounir 3 , S. Wicem 1 , D. Jamel 1 1 Hopital Habib Bourguiba, Radiation Oncology, Sfax, Tunisia 2 Hopital Habib Bourguiba, ORL, Sfax, Tunisia 3 Hopital Habib Bourguiba, Medical oncology, Sfax, Tunisia Purpose or Objective Weight loss (WL) during radiotherapy for nasopharyngeal carcinoma has recently been identified as a negative prognostic factor. The aim of this study was to identify the predictive factors of WL. Material and Methods A total of 54 patients treated with concurrent radiotherapy and weekly cisplatin chemotherapy were enrolled in this study. Fifty per cent of patients received intensity modulated radiotherapy (IMRT). Prescribed dose was 66-70 Gy 2Gy per fraction. Pre-radiotherapy weight was measured in the first day of treatment and post- radiotherapy weight in the last day. Patients were followed weekly during treatment to determine the acute toxicities which were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v.4. The studied factors influencing the WL were: age at diagnosis (<60 vs ≥ 60); sex; radiotherapy technique (3D conformal radiotherapy vs IMRT) ; xerostomia (G0-1 vs G≥2) and oral mucositis (G0-1 vs G≥2). Independent sample T test was used of intergroup comparisons and p < 0.05 was considered statistically significant. Results The mean WL was 6,56kg (0-14kg). Patients treated with IMRT had a mean WL of 5.3 kg vs 7.8 kg with 3D radiotherapy (p=0.01). Patients with mucositis ≥ G2 had a mean WL of 7.68 kg vs 4.66 kg for patients with mucositis

2 (5.1% ) 8 (20.5 %) 22 (56.4 %) 7 (17.9 %)

11 (28.2 %) 14 (35.9 %) 8 (20.5 %) 6 (15.9 %)

Surgery+adjuvant CCRT

A

T1 6(15.4% )

B

T2 5(12.8% )

Surgery+adjuvant RT

Surgery/Surgery+adju vant chemotherapy

C

T3 16(41.0 %)

D

T4 12(30.8 %)

Definite RT/CCRT