Tehran University of Medical Sciences Journal of Pharmaceutical Care 2322-4630 6 3-4 2019 07 16 The Effect of Selenium Serum Levels on Oral Mucositis Frequency and Severity in Patients with Head and Neck Radiation 39 43 Elahe Laali Department of Clinical Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences Soheila Manifar Department of Radiation-Oncology, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran Ali Kazemian Department of Oral and Dental Diseases, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Zahra Jahangard-Rafsanjani Department of Clinical Pharmacy, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran Kheirollah Gholami Department of Clinical Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences . AND Research Center for Rational Use of Drugs, Tehran University of Medical Sciences, Tehran, Iran 2018 12 18 2018 12 25 Background: Radiotherapy as an important treatment modality in head and neck cancer diminishes reactive oxygen system which causes damages to the normal cell/tissue function and cell cycle regulation. Selenium involve in both antioxidant and anti-inflammatory systems. In this study, we aimed to investigate whether there is a difference between selenium levels before and after radiotherapy and the effects of serum selenium levels on radiotherapy oral mucositis (OM) patients undergoing radiation for head and neck cancer. Methods:This prospective study includes 42 head and neck cancer patients treated by external beam radiotherapy at the Cancer Institution of Imam Khomeini Hospital, Tehran University of Medical Sciences. Plasma selenium concentrations were determined before and after RT. The grade of OM was evaluated weekly by the WHO oral toxicity scale. Results: The mean patient age was 54.74 (range=18-81) years. For most of the patients, the histopathological diagnosis of cancer was squamous cell carcinoma (n=28 (66.7%)).  There was no significant difference in serum Se levels before and after RT (85.38±30.63 before radiation and 90.32±33.26 after radiation, p-value >0.05). ). Moreover, there was no significant difference between levels of Se after RT in patients who developed severe OM and who did not. Conclusion: In our study, we couldn’t find any significant difference in the levels of Selenium before and after radiotherapy and also there was no association between Selenium levels and oral mucositis developing.     https://jpc.tums.ac.ir/index.php/jpc/article/view/246