JMIR Publications

ABSTRACT

Background:

In recent years, the global incidence of thyroid cancer has been increasing.

Objective:

This study aimed to examine the association between Hashimoto’s thyroiditis (HT) and papillary thyroid cancer (PTC) progression under active surveillance (AS).

Methods:

Our retrospective study was conducted at Peking University Third Hospital and included 203 PTC patients who underwent AS for ≥ 6 months before surgery. Patients were first categorized into two groups: the HT group (n=90) and the non-HT group (n=113). Cox proportional hazards models were then used to evaluate the association between HT and PTC progression during AS, adjusting for age, sex, baseline tumor size, body mass index (BMI), pregnancy status, number of tumor foci and thyroid stimulating hormone (TSH) level. Subgroup analyses stratified by the six covariates mentioned above were also applied to explore the potential effect modification.

Results:

No significant difference was observed between the HT and Non-HT groups in PTC progression-free survival (hazard ratio [HR], 1.11; 95% CI, 0.61–1.99; P=0.738), tumor enlargement-free survival (HR, 1.02; 95% CI, 0.56–1.86; P=0.952) or lymph node metastasis-free survival (HR, 1.76; 95% CI, 0.31–10.12; P=0.524). Subgroup analyses revealed a potential interaction between HT and BMI: Among patients who were overweight or obese (BMI>24 kg/m²), HT was significantly associated with an increased risk of disease progression (HR, 6.32; 95% CI, 1.84–21.69; P=0.003), while among patients with BMI≤24 kg/m2, no association between HT and progression risk was observed (P>0.05).

Conclusions:

We found no evidence of association between HT and PTC progression during AS. However, the relationship between HT and PTC progression may be modified by obesity status.