Cancer Treatment and Research Communications (Jan 2023)
Comparison of sequential versus simultaneous integrated boost of volumetric modulated arc therapy in treatment of oropharyngeal carcinoma
Abstract
Objective: Volumetric modulated arc therapy (VMAT) is a useful treatment technique that can reduce treatment time while producing improved dose distribution to target structures. The main aim of the study is to evaluate the outcome of oropharyngeal cancer patients treated with VMAT, sequential (SEQ) versus simultaneous integrated boost (SIB) technique in terms of survival and failures and to assess late radiation toxicities with their dosimetric parameters. Material and Methods: Total 54 patients of histologically proved oropharyngeal cancer patients treated by definitive radiotherapy using VMAT technique in January 2019 to December 2020 were followed up and evaluated in terms of survival, patterns of failure and late radiation toxicities by RTOG toxicity criteria. Results: After a median follow up of 12 months, overall survival (OS) and disease free survival (DFS) were 64.8% and 48.1% respectively. In terms of patterns of failure, 44.4% showed local recurrence, 7.4% as regional relapse and 3.7% showed distant metastasis. While comparing sequential versus SIB, no significant difference was found in OS (64.9% vs. 59.8%, p = 0.689), DFS (52.8% vs. 35.3%, p = 0.266), local control (LC) (58.3% vs. 47.1%, p = 0.437) and regional control (RC) (94.3% vs. 88.2%, p = 0.151) respectively. Among late radiation toxicities, the most common were xerostomia (42.2% for SEQ and 24.2% for SIB group), dysphagia (33.3% for SEQ and 15.1% for SIB group) and hoarseness of voice (15.1% for SEQ and 12.1% for SIB group). Conclusion: SIB technique proved better than SEQ technique in terms of pattern of failure or late toxicity, but no significant difference can be reported.
