Analysis Of Risk Factors For Radiation Related Hypothyroidism In Head And Neck Cancer

Objective(s):By analyzing the clinical indicators,location of head and neck tumors,thyroid volume factors,radiation site,and dose in patients with head and neck malignant tumors undergoing radiotherapy,the influencing factors on the occurrence of radiation induced hypothyroidism(RIHT)were analyzed.Methods:This study collected 167 patients with head and neck tumors treated at our hospital from September 2020 to December 2022,including nasopharyngeal cancer,laryngeal cancer,oropharyngeal cancer,salivary gland cancer,nasal cavity cancer,and oral cancer.All patients received intensity modulated radiation therapy.Collect general information and clinical pathological indicators of patients,including gender,age,Body Mass Index(BMI),tumor staging,grading,and metastasis status.Collect thyroid function indicators and thyroid volume before radiotherapy,three months after radiotherapy,and twelve months after radiotherapy for patients.Collect patient blood for blood biochemical examination,with radiation induced hypothyroidism as the observation focus.Summarize and statistically analyze all the data collected above,and explore the factors affecting radiation induced hypothyroidism in patients.Results:Sixteen patients who did not meet the inclusion criteria were excluded,and 167 patients were actually included.The pathological types of tumor included 88 cases of nasopharyngeal carcinoma,35 cases of laryngeal carcinoma,16 cases of oropharyngeal carcinoma,10 cases of salivary gland carcinoma,7 cases of nasal cavity carcinoma and 11 cases of oral cancer.Among them,31.74%of the patients had RIHT(53/167).Further analysis showed that lymph node metastasis of head and neck cancer,thyroid volume,thyroid radiation volume dose V50 were risk factors for RIHT,and other indicators were not statistically significant.Conclusions:The occurrence of radiation hypothyroidism is closely related to radiotherapy for head and neck malignant tumors;The longer the time after radiotherapy,the higher the incidence of RIHT.The N-stage of tumor,thyroid volume before radiotherapy,and thyroid dose volume parameter V50 are risk factors for radiation induced hypothyroidism,which are related to the occurrence of radiation induced hypothyroidism.For patients in stage N2-3 with thyroid volume<10.87 ±3.50 cm3 before radiotherapy,more attention should be paid to thyroid V50,and close review of thyroid function is required during follow-up.