The association of thyroid peroxidase antibodies with microvascular invasion in patients with papillary thyroid carcinoma.

PURPOSE: Papillary Thyroid Carcinoma (PTC) is the most prevalent thyroid malignancy. Current evidence on the association between thyroid peroxidase antibody (TPOAB) levels and microvascular invasion (MVI) in PTC is limited. The aim of this study was to investigate the association between TPOAB and MVI in patients with PTC.

METHODS

This retrospective study included patients with PTC who underwent surgery at the First People's Hospital of Zunyi between May 22, 2022, and March 06, 2024. Preoperative TPOAB levels were recorded, along with several potential confounding factors, including sex, age, BMI, smoking, drinking, tumor size, multiple foci, thyroglobulin antibody (TGAB), thyroglobulin (Tg) and preoperative thyroid function. TPOAB levels were log-transformed and denoted as lnTPOAB for analysis. MVI was determined based on the postoperative pathology reports. Multivariable logistic regression analysis was conducted to investigate the association between lnTPOAB and MVI risk, adjusted for confounding factors. A restricted cubic spline model was employed to examine the nonlinear relationship between ln TPOAB and MVI. The inflection point was calculated using a two-piece linear-regression model. Subgroup analyses were performed to verify the association between TPOAB and MVI.

RESULTS

A total of 409 participants were included in the study. In the multivariable logistic regression model, after adjusting for all potentially confounding variables, the odds ratio (95% confidence interval) of lnTPOAB associated with MVI was 1.18 (1.03, 1.34; P = 0.013). The restricted cubic spline demonstrated a non-linear association between lnTPOAB and MVI. The two-piecewise regression model indicated that the inflection point was - 1.1, corresponding to a raw estimate of TPOAB of 0.33 IU/ml. Subgroup analyses further validated the positive association between TPOAB levels and MVI in patients with PTC.

CONCLUSIONS

Elevated TPOAb levels were independently associated with higher odds of MVI. Therefore, TPOAb may act as a supportive preoperative risk marker, helping to guide the extent of surgery and, together with tumor size and biochemical markers, customize early postoperative follow-up strategies. However, its clinical value still requires confirmation in prospective studies.

TRIAL REGISTRATION: ChiCTR2400084886, date of registration: May 27, 2024, retrospectively registered.