Effects of optimizing target volume on oral mucosal reaction and salivary gland function in oropharyngeal cancer patients undergoing intensity-modulated radiotherapy / 中国医学物理学杂志

ABSTRACT

Objective To analyze the effects of target volume optimization on oral mucosal reaction and salivary gland function in oropharyngeal cancer patients receiving intensity-modulated radiotherapy(IMRT).Methods A total of 120 patients with oropharyngeal cancer admitted to Affiliated Hospital of Jiangsu University from April 2020 to August 2022 were selected and randomly grouped into control group(n=60,conventional IMRT)and treatment group(n=60,cervical region Ⅱ and the oral target region were optimized during IMRT).The therapeutic efficacy,parotid gland dose,incidence of acute oral mucosal reaction,dry mouth and oral pain at 3 months after IMRT were compared between two groups.The resting-state apparent diffusion coefficient(ADC)values of parotid and submandibular glands at different time points(before radiotherapy,the 4th week of radiotherapy,the end of radiotherapy and 3 months after radiotherapy)were recorded.Results The difference in the objective reaction rate between two groups was trivial[80.00％(48/60)vs 75.00％(45/60),P>0.05].The mean dose(Dmean)and V34 of the unaffected parotid gland and the Dmean and V30 of the oral cavity in treatment group were lower than those in control group(P<0.05).The incidences of acute oral mucosal reaction,dry mouth and oral pain at 3 months after radiotherapy in treatment group were 41.67％,50.00％,and 58.33％,lower than those in control group(75.00％,78.33％,and 85.00％)(P<0.05).The resting-state ADC values of parotid and submandibular glands at the 4th week of radiotherapy,the end of radiotherapy,and 3 months after radiotherapy in both two groups were higher than those before radiotherapy(P<0.05).At the 4th week of radiotherapy,the end of radiotherapy,and 3 months after radiotherapy,the resting-state ADC values of parotid and submandibular glands in treatment group were lower than those in control group(P<0.05).Conclusion Optimizing target volume during oropharyngeal IMRT can effectively prevent the occurrence of radiation-induced mucositis,alleviate oral mucosal reaction,oral pain and dry mouth,reduce parotid gland dose,and diminish the effects of IMRT on salivary gland function in patients.