ESTRO 2023 - Abstract Book

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ESTRO 2023

1 Basaksehir Cam and Sakura city Hospital, Radiation Oncology, Istanbul, Turkey; 2 Altınba ş University, Oral and Dental Health Department, Istanbul, Turkey; 3 University of Helsinki, Department of Oral and Maxillofacial Diseases, Helsinki, Finland; 4 University of Helsinki, Department of Oral and Maxillofacial Diseases, Helsinki, Finland Purpose or Objective While mucositis characterized by inflammatory and ulcerative changes occurring in the oral mucosa starts to be observed from the first weeks in patients receiving radiation therapy for the head and neck, it may lead to severe tissue distructive complications that can affect the course of treatment in a significant majority of patients. Matrix metalloproteinases (MMPs) are collagenases capable of destroying the extracellular matrix and the basal membrane both in physiological tissue repair and in pathological destruction processes. While MMP-8 in the MMPs group is a prominent biomarker in destructive periodontal diseases, it is also associated with inflammatory conditions, cancers, and systemic diseases. The aim of the study is to present a comparative analysis of the change in the level of oral fluid active MMP-8 (aMMP-8) in the 3-week radiotherapy process in head and neck cancer patients who had mucositis symptoms during the radiotherapy process. Materials and Methods Fifteen head and neck cancer patients with mucositis symptoms were included in this analysis report, in accordance with the RTOG grading system. Initial periodontal status analysis of patients was performed by a periodontologist (M.K.). Quantitative analysis of aMMP-8 was carried out by using the oral rinse water collected from patients in the 1st and 3rd weeks prior to radiotherapy, using aMMP-8 chairside point-of-care kits (PerioSafe®/ORALyzer®). Results Thirteen male and two female patients (mean age 54.14 ± 13.69) were included in the study. All patients were diagnosed with periodontitis (Stage II=4, Stage III=6, Stage IV= 5, Grade C=15). Grade I mucositis was observed in 8 patients, Grade II mucositis in 5 patients, and Grade III mucositis in 2 patients. Although an average increase in oral aMMP-8 levels was observed during the 1st and 3rd weeks of radiotherapy compared to the pre radiotherapy period, a statistically significant difference was only determined in the 3rd week (p<0.05). Conclusion While oral mucositis is one of the most important complications seen in patients receiving radiation therapy in the head and neck region, it can lead to a decrease in quality of life and an increase in the cost of treatment. aMMP-8 which is a tissue destructive and dysimmune oral fluid biomarker that can increase in destructive periodontal conditions according to our findings has the potential to be a measurable chairside biomarker that can be associated with oral mucositis in head and neck cancer patients undergoing radiotherapy. On the other hand, biomarkers of oral fluids that have the potential to be collected by non-invasive methods can be a source of data that can provide and reflect information about the risks of oral complications of radiotherapy. A larger number of comparative cohort studies involving biomarkers associated with inflammation and tissue destruction are required. 1 Wan Fang Hospital, Taipei Medical University, Department of Radiation Oncology , Taipei, Taiwan; 2 Taipei Medical University, Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei, Taiwan; 3 Taipei Medical University, Graduate Institute of Data Science, Taipei, Taiwan; 4 Shuang Ho Hospital, Taipei Medical University, Department of Neurosurgery, Taipei, Taiwan Purpose or Objective Research on cancer survivorship associated with nasopharyngeal carcinoma (NPC) is rare. The advance of radiotherapy technique diverse the long-term analytic variable related with treatment. We conducted a multicenter real-world study, focused on IMRT era technique, to evaluate the relevance between cerebrovascular accidents (CVA) and those who receive concurrent chemoradiotherapy in patient with nasopharyngeal carcinoma. Materials and Methods There are 976 patients with nasopharyngeal carcinoma treated at Taipei Medical University Hospital, Shuang-Ho Hospital and Wan-Fang Hospital between 2002-2019. 504 patients are newly diagnosed with NPC and treated with concurrent chemoradiotherapy. Host factors include age, sex, body height, body weight, alcohol drinking, betel nut chewing, smoking, etc.; tumoral factors include clinical T, clinical N, clinical cStage, histology type and treatment related factors include radiotherapy dose, gap between simulation and treatment, radiotherapy treatment duration etc. are collected. Previous medical history with diabetes meatus, hyperlipidemia, hypertension or ischemic heart disease is also retrieved by reviewing the patient’s outpatient clinical record. Recurrence patten, date, survival status and cerebrovascular accident (CVA) are also collected as major outcome for survival analysis and event analysis. Results In this cohort, there are 504 patients are newly diagnosed with NPC. There are 67.26% male patient. The main age group is between 40-60, which account 51.2% of the cohort. Most of the patient are stage IV (40.7%) and stage III (25.8%.) The crude one year-overall survival is 93.2%, and five-year overall survival 68.9%. There are 56 (11.1%) patients then develop cerebrovascular accidents after receiving concurrent chemoradiotherapy. The chi-square test shows clinicalN(p=0.0235), clinical TNM stage(p=0.0222), curative radiotherapy dose or not (p<0.0001) are statistically related with CVA. For COX proportional hazard model, age as continuous variable (HR 1.033, p<0.05), obesity (HE 1.938, p<0.05) show statically significant. And the CVA-event-free survival of cerebrovascular accident is related to age (p=0.0047), obesity or not (p=0.0496), curative radiotherapy or not (p=0.0418) in log-rank test. PO-1227 A multicenter real-world study reviewing relevance between CCRT and CVA for NPC: In the IMRT era J. WU 1,2 , M. Hsu 3,4

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