RESUMO
PURPOSE: The well-established clinical efficacy of photobiomodulation (PBM) therapy in management of oral mucositis (OM) is leading to increasing use in oncology care. This protection and enhanced repair of damage to mucosal tissue have led to the question of the potential effects of PBM therapy on pre-malignant and malignant cells. The purpose of this study was to examine the outcome of cancer therapy and incidence of tumor recurrence in locally advanced oral squamous cell carcinoma (OSCC) patients treated with PBM therapy for OM. METHODS: A retrospective clinical analysis of 152 advanced OSCC patients treated with prophylactic PBM therapy for radiotherapy-induced OM from January 2009 to December 2014 was conducted. RESULTS: Of the 152 OSCC patients treated with PBM therapy in this study, 19 (12.5%) had stage III and 133 (87.5%) had stage IV tumors. Of these, 52 (34.2%) received initial treatment with surgery followed by adjuvant radiotherapy, 94 (61.8%) with exclusive chemoradiation, and 6 (4%) with induction chemotherapy followed by surgery and radiotherapy. After a mean follow-up of 40.84 (± 11.71) months, the overall survival and disease-free survival rates were 46.7 and 51.8%, respectively. Forty-five (29.6%) patients developed local-regional recurrence, 10 (6.57%) patients developed distant relapse, and 19 (12.5%) developed new (second) primary tumors. CONCLUSIONS: Clinicopathological features and survival outcomes in the PBM-treated patients were similar to previously published data for conventional treatments in patients with advanced OSCC. In this study, prophylactic use of PBM therapy did not impact treatment outcomes of the primary cancer, recurrence or new primary tumors, or survival in advanced OSCC patients.