Oral adverse effects of head and neck radiotherapy with/without chemotherapy in a southern Brazil hospital.

The aim of this study was to evaluate the main oral adverse effects and their relationship with dental care before radiotherapy (RT) and combined RT and chemotherapy (RT+CT). Additionally, we assessed the association of other risk factors with the development of these adverse effects. This paper is a retrospective cross-sectional analytical study of data from medical records of patients with head and neck cancer (HNC) who underwent RT or RT+CT attended at the stomatology unit in a southern Brazil hospital. The records of 78 patients with HNC were accessed. Demographic data, tumor characteristics, cancer treatment, follow-up data, adverse effects, and dental treatment prior to RT were evaluated individually for descriptive analysis. Kaplan-Meier survival curves were plotted. Risk factors were assessed using chi-square or Mann-Whitney test. The results showed that most patients were male (88.3%) in their 6th decade of life. Tumors were mostly located in the oral cavity (52.6%) and squamous cell carcinoma was the main diagnosis (94.8%). Most cases were diagnosed in advanced stages (67.9%). RT was of 2D or 3D types in 93.6% of patients. Oral adverse effects were observed in 94.7% of patients treated with RT or RT+CT. Osteoradionecrosis (ORN), oral mucositis (OM), candidiasis, and xerostomia were the main complications. Patients who received 2D RT had higher risk of developing ORN and xerostomia compared to those who received 3D RT. The risk of developing ORN was higher in smokers compared to non-smokers and in patients who had not previously consulted a dentist. This study showed that patients who underwent RT for HNC have a high occurrence of oral complications. Dentists play a key role in the management of these oral side effects.