Optimization Of Parotid Gland Delineation Approaches Combined With Traditional Chinese Medicine Intervention To Improve Parotid Gland Function In Patients With Nasopharyngeal Carcinoma

Objective:To explore the effective protection of parotid gland function injury caused by nasopharyngeal carcinoma(NPC)radiotherapy in the era of intensity modulated radiotherapy(IMRT).Methods:A total of 21 patients with locally advanced nasopharyngeal carcinoma who received IMRT concurrent chemotherapy in the Affiliated Hospital of North Sichuan Medical College from August 2020 to July 2021 were enrolled as the experimental group,and 20 patients matched with the experimental group were retrospectively selected as the control group.The experimental group delineated the target area of the parotid gland with the demarcation between the target area and the outer area,and received traditional Chinese medicine Gan Luyin orally from the radiotherapy.Both groups underwent parotid SPECT before radiotherapy,at 15 times of radiotherapy,at the end of radiotherapy,1 month after radiotherapy,3 months after radiotherapy,and 6 months after radiotherapy.Uptake Index(UI)and Excretion Index(EI)were calculated,and patients were followed up for the degree and grade of xerostomia at the above time points.The parotid gland function damage and subjective xerostomia symptom classification were compared between the two groups,and the protective effect of parotid gland delineation combined with traditional Chinese medicine intervention on parotid gland function in patients with nasopharyngeal carcinoma was analyzed.Result:1.Using different parotid gland delineation modes,delineating the parotid gland by the demarcation of the target area and the outer boundary of the parotid glands The radiation doses(Dmax,Dmin,Dmean,D50)of the bilateral parotid glands were all smaller than those of delineating the parotid glands as a whole(P<0.01),with statistical significance;2.At the end of radiotherapy and 6 months after radiotherapy,the parotid gland function damage in the experimental group was lighter than that in the control group(P<0.05),but there was no significant difference between 15 times of radiotherapy and 1 and 3 months after radiotherapy(P>0.05).3.At 15 times of radiotherapy,at the end of radiotherapy,and at 6 months after radiotherapy,the degree of xerostomia in the experimental group was lighter than that in the control group(P<0.05),but there was no statistical difference between the two groups at 1 and 3 months after radiotherapy(P>0.05).Conclusion:1.Compared with the conventional delineation mode,delineating the parotid gland with the demarcation between the target area and the outer area can reduce the dose of parotid gland irradiation.2.Optimization of parotid gland delineation combined with traditional Chinese medicine intervention can improve the effect of radiotherapy on parotid gland function in patients with nasopharyngeal carcinoma to a certain extent,and relieve the symptoms of xerostomia.