Efficacy of Thyroid Hormone Replacement Therapy in Nasopharyngeal Carcinoma Patients with Radiation-Induced Subclinical Hypothyroidism.

Hypothyroidism is a common side effect of radiotherapy for nasopharyngeal carcinoma, with subclinical hypothyroidism being the focus of this study.

• Patients diagnosed with nasopharyngeal carcinoma who developed subclinical hypothyroidism after definitive radiotherapy between September 2019 and December 2020 were selected.
• The median follow-up period was 14.5 months.
• Assessments were conducted before thyroid hormone replacement therapy and after maintaining euthyroidism for 6-12 months through thyroid hormone replacement therapy.

The most prevalent hypothyroid symptoms reported by nasopharyngeal carcinoma patients with radiation-induced subclinical hypothyroidism were chills, fatigue, weight gain, and limb numbness.

• The median score of hypothyroid symptoms was 5.5 out of 19 points.
• Chills were the most common symptom, reported by 65.0% of patients.
• Fatigue was reported by 50.0% of patients.
• Weight gain was reported by 45.0% of patients.
• Limb numbness was reported by 40.0% of patients.

Thyroid hormone replacement therapy did not significantly improve quality of life in nasopharyngeal carcinoma patients with radiation-induced subclinical hypothyroidism.

• Quality of life was assessed using the SF36 Brief Health Status Scale before and after 6-12 months of thyroid hormone replacement therapy.
• Statistical analyses were performed using matched samples T-test or Mann-Whitney U test.
• No statistically significant improvement in SF36 scores was observed following treatment.

Thyroid hormone replacement therapy did not significantly alleviate hypothyroidism-related symptoms in patients with radiation-induced subclinical hypothyroidism.

• Hypothyroidism-related symptoms were assessed using the Hypothyroidism-related Symptom Questionnaire before and after achieving euthyroidism through thyroid hormone replacement therapy.
• No statistically significant reduction in hypothyroid symptom scores was found following treatment.
• Assessments were conducted via trained questionnaires.

Thyroid hormone replacement therapy did not significantly improve lipid profiles, though a downward trend in serum cholesterol levels was observed.

• Lipid profiles were assessed at baseline and after 6-12 months of thyroid hormone replacement therapy.
• No statistically significant improvement in blood lipid profiles was observed (overall).
• There was an observed downward trend in serum cholesterol levels following treatment (P=0.052), which did not reach statistical significance.