ESTRO 37 Abstract book

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ESTRO 37

Electronic Poster: Clinical track: Head and Neck

EP-1104 Prognostic value of pre-treatment neutrophils in locally advanced head and neck cancer R. Carmona-Vigo 1 , J.M. Blanco Suárez 1 , M. Lloret Sáez- Bravo 1 , P.C. Lara Jiménez 1 1 Las Palmas de Gran Canaria, Radiation Oncology, Las Palmas de Gran Canaria, Spain Purpose or Objective To investigate whether pre-treatment neutrophil counts in peripheral blood can be a predictive assay for clinical outcome in radio-chemo-immunotherapy of head and neck cancer. Material and Methods Fifty-three patients (13 cases ST.III and 40 cases ST.IV) were prospectively included in this study from September 2009 to November 2016. Radiotherapy consisted in hyper fractionated radiotherapy: 1.15-1.20 Gy/fraction, BID, 5 days/week during 7 weeks. The average dose administered was 80.2 Gy (79.2-80.5). Carboplatin was administered 5 mg/m2 before each fraction of radiotherapy. Cetuximab was administered 400 mg/m2 one week before hyperfractionated radiotherapy and then 250 mg/m2 weekly while radiotherapy. Seven patients were not evaluable for response. Neutrophil counts were registered before treatment in routine blood test. Results Forty-six evaluable patients showed objective response. The local relapse-free survival, loco-regional relapse-free survival, and cause specific survival was 48.0 (8.4%), 42.2 (7.9%), and 49.4 (8.8%) at 5 years, respectively. Neutrophil counts were inversely related to tumour response (p=0.032). Complete response patients (28) showed a pre-treatment neutrophil counts of 5.539 ± 2.301, median: 4.985 (range: 2.17-11.30), compared to 6.144 ± 2.239, median: 5.360 (range: 3.02-10.10) for those with partial response (13), and 9.926 ± 8.145, median: 7.440 (range: 3.52- 24.00) for those showing progressive disease (5). In multivariate analysis, age, sex, clinical stage, rash and neutrophil counts were included. Only neutrophils counts were predictive for Loco-Regional Progression Free Survival p=0.050 Exp (B) 1.121 (95% ICExp (B) 1.0-1.256), Disease Free Survival p=0.030 Exp (B) 1.128 (95% ICExp (B) 1.01- 1.2567) and Cause Specific Survival p=0.026 Exp (B) 1.156 (95% ICExp (B) 1.01-1.313). Conclusion Pre-treatment neutrophil counts could be an easy predictive assay for clinical outcome in radio-chemo- immunotherapy of head and neck cancer. EP-1105 Effectiveness of combined orbital radiation and systemic steroids in Graves` Ophthalmopathy R. Carmona-Vigo 1 , I. San Miguel Arregui 1 , L. Luque Japón 2 , P.C. Lara Jiménez 1 1 Las Palmas de Gran Canaria, Radiation Oncology, Las Palmas de Gran Canaria, Spain 2 Las Palmas de Gran Canaria, Medical Physicist, Las Palmas de Gran Canaria, Spain Purpose or Objective To evaluate the clinical response of patients with Graves’ Ophthalmopathy given low-dose orbital radiotherapy with a protracted fractionation scheme. Material and Methods Patients with Graves’ Ophthalmopathy were included prospectively in this study between 2011 and 2016. Twenty nine patients (49 orbits) received orbital radiotherapy by volumetric modulated arc therapy with a total dose of 10 Gy, 1 Gy/week. Of these, twenty five patients received a megadose (500 mg the first six fractions; 250 mg the four remaining ones) of metilprednisolona i.v. before every radiotherapy fraction. Patients were evaluated clinically at 6 months after treatment. Clinical response assessment was carried

EP-1103 Tumour volume as a prognostic marker in early-stage nasopharyngeal carcinoma S. Poh 1 , S. Mueller 2 , W. Lam 3 , P. Teo 4 , H. Tan 2 1 National Cancer Centre- Singapore, Department of Radiation Oncology, Singapore, Singapore 2 National Cancer Centre- Singapore, Department of Surgical Oncology, Singapore, Singapore 3 Singapore General Hospital, Department of Nuclear Medicine, Singapore, Singapore 4 National Cancer Centre- Singapore, Department of Oncological Imaging, Singapore, Singapore Purpose or Objective Nasopharyngeal carcinoma (NPC) is endemic in Southeast Asia and responsible for significant morbidity and mortality. The current TMN staging system utilizes anatomical site involvement in stage determination, which is correlated to, but not necessarily directly reflecting tumour volume. In advanced disease, there is growing evidence to show that tumour volume has a significant role in prognostication. However, in early NPC, there is little and conflicting evidence regarding the role of tumour volume in prognostication; and available data was obtained in the era before the advent of intensity-modulated radiation therapy (IMRT), which has led to improved treatment efficacy. In addition, the results obtained in advanced NPC may not necessarily be directly applicable to that of early NPC, as standard treatment in advanced NPC is concurrent chemoradiation while that in early NPC is usually radiotherapy alone. The aim of this study was to investigate the prognostic relevance of tumour volume in early stage NPC. Material and Methods 89 patients with Stage 1 (n=33) and 2 (n=56) NPC, who underwent IMRT at our centre between 2006 and 2014, were included in this study. Primary tumour volume (PrTV), nodal tumour volume (NdTV) and total tumour volume (TtTV) were calculated based on pre-treatment CT scans and MRI scans. Overall survival (OS) and local recurrence free survival (LRFS) were analyzed using the Kaplan-Meier estimate and a Cox proportional hazard model was employed to assess for independent association of these variables with OS and LRFS. Results Mean follow up was 54 months with 18% (n=16) of the patients developing a recurrence and 8% (n=7) dying of their disease. Mean PrTV was 5.13ml 3 for Stage 1 and 9.94ml 3 for Stage 2 (p<0.01). Mean TtTV was 20.43ml 3 for Stage 2 (p<0.01). PrTV and TtTV showed significant association with both LRFS and OS when assessed with a Cox regression univariate analysis and Cox backward logistic regression. Cut - off volumes were derived using a receiver operating characteristic (ROC), which returned a cut - off PrTV of 7.7ml 3 and TtTV of 13.3ml 3 . Patients with a PrTV greater than 7.7ml 3 showed significant worse LRFS (p<0.01). TtTV above 13.3ml 3 was associated with a worse LRFS (p=0.01) and OS (p=0.05). On the other hand, analysis of the above data based purely on AJCC Stage alone did not show a significant correlation with OS (p=0.6) or LRFS (p=0.12). Conclusion Tumour volume, in particular TtTV, has been shown to be useful in prognostication for local recurrence and overall survival in patients within our cohort suffering from early stage NPC and may serve as a suitable adjunct to AJCC staging. Further work should be done to verify these results on a larger cohort, and this may pave the way for the consideration of possible treatment escalation, such as trials with the addition of concurrent chemotherapy in early NPC cases with bulky disease.