ESTRO 2022 - Abstract Book

S913

Abstract book

ESTRO 2022

Conclusion Although none of the patients in our study had marked vision loss and retinal abnormalities with the examination, OCTA findings showed that perifoveal and parafoveal vascularity were statistically significantly affected due to the RT.

PO-1078 Obesity potential biomarker for prediction of OS in head and treated with radio-chemotherapy

G. Gadducci 1 , N. giannini 2 , G. malfatti 3 , N. coccia 2 , T. fuentes 2 , A. gonnelli 2 , E. calistri 2 , F. paiar 2

1 azienda ospedaliera universitaria pisana , radiotherapy, PISA, Italy; 2 azienda ospedaliera universitaria pisana, radiotherapy, PISA, Italy; 3 azienda ospedaliera universitaria pisana,, radiotherapy, PISA, Italy Purpose or Objective The prognosis of head and neck cancer patients is traditionally determined using several different clinical characteristics such age, stage, high alcohol consumption and cigarette smoking. The purpose of this study was to evaluate the prognostic relevance obesity (BMI> 29.9 Kg/m2) head and neck cancer (HNC) patients treated with radio-chemotherapy (RT/CT) at the Department of Radiotherapy, University of Pisa. Materials and Methods BMI was retrospectively assessed in 134 HNC locally advanced patients (median age 63,5,range 20-84,M:F 4:1) treated between January 2015 to June 2020. The following were the inclusion criteria: All patients (> 18 years old) with locally advanced squamous cell carcinoma underwent adjuvant or exclusive radiotherapy concomitant with cisplatin, BMI was calculated before the beginning of RT/CT. For the present study, overall survival (OS) and progression free survival (PFS) were defined as days between the end of the treatment and death or progression date of last follow-up. Results Patients with a BMI above 29.9 Kg/m 2 showed a favorable trend regarding the overall survival (p= 0,086; HR 0.489, IC 0.211-1,082) in univariate analysis. Instead BMI was not corralated with PFS (p= 0,644; HR 0.802, IC 0.211-1,082). Conclusion In our study we have shown that obesity is a potential biomarker for patients with locally advanced HNC treated wih radiotherapy concomitant with cisplatin. The role of obesity and BMI remain controverse in literature. These findings can be explained with a better nutritional status before the beginning of the therapy compared with normal and underweight population. More prospective studies with larger population are required 1 Seoul National University Hospital, Department of Radiation Oncology, Seoul, Korea Republic of; 2 Seoul National University, Department of Statistics, Seoul, Korea Republic of; 3 Seoul National University, Department of Statistics, Seoul, Korea Republic of Purpose or Objective The assessment schedule after definitive loco-regional treatment for head and neck cancer (HNC) is determined arbitrarily in daily clinical practice. Here, we propose the optimal assessment schedule for each subgroup stratified by subsites and HPV status in HNC using a parametric model of standardized event-free survival (EFS) curves. Materials and Methods A total of 673 patients with locally advanced stage HNC (227 nasopharynx (NPC), 237 HPV-positive oropharynx (HPV+ OPC), 47 HPV-negative oropharynx (HPV- OPC), 97 larynx (LC), and 65 hypopharynx cancer (HPC)) and 113 patients with early- stage larynx cancer (ELC) who completed definitive loco-regional treatment at two tertiary referral university hospitals between 2008 and 2019 were retrospectively analyzed. EFS was defined as the period from the end of treatment to the date of any event (tumor recurrence or secondary malignancies). EFS curves were estimated using the piecewise exponential survival model. The criterion of a 5% event rate among the remaining patients at each observation period was used to determine the optimal assessment time point. The benefit from the optimal schedule was measured for the comparison with the institutional policy, which followed-up every two months for the first year, every three months for the following two years, and every 6-12 months thereafter. Results With a median follow-up of 57.8 months (range, 6.4 -158.1), the event rates of NPC, HPV+ OPC, HPV- OPC, LC, HPC, and ELC were 18.9%, 15.2%, 36.2%, 30.9%, 44.6%, and 13.3% respectively. The optimal follow-up intervals for HPC/LC/NPC were every 1.9/3.0/5.5 months until 16.5 months after treatment, every 3.7/5.8/10.6 months from 16.5 to 25 months, every 9.0/14.2/26.0 months from 25 to 99 months, and open follow-up thereafter. For HPV- OPC, surveillance every 2.5 months until 16.5 months after treatment, every 4.9 months from 16.5 to 25 months, every 12.1 months from 25 to 99 months are recommended. In contrast, for HPV+OPC, optimal intervals were every 7.1 months until 16.5 months after treatment, every PO-1079 An optimal assessment schedule in the head and neck cancer using parametric modeling H.I. Lee 1 , J. Lee 2 , H. Wu 1 , J.H. Kim 1 , Y. Kim 3 , J.H. Lee 1 , K. Eom 1