Correlation of TgAb With Clinicopathological Features and Unfavorable Efficacy of 131I Ablation in PTC.

Abstract

Context: Papillary thyroid carcinoma (PTC) is the most common malignant thyroid cancer. Several clinicopathological features may affect therapeutic efficacy.

Objective: To analyze the relationship between thyroglobulin antibodies (TgAb) with clinicopathological features and efficacy of 131I ablation in PTC patients.

Methods: A total of 548 PTC patients who underwent total thyroidectomy and subsequent 131I ablation were enrolled. The clinicopathological features between TgAb-positive and TgAb-negative groups were compared. The clinicopathological characteristics and risk factors affecting the efficacy of 131I ablation were analyzed.

Results: A total of 157 cases (28.65%) were in the preoperative TgAb-positive group and 391 cases (71.35%) were in the TgAb-negative group. The TgAb-positive group was younger and had a higher proportion of females, anti-thyroid peroxidase antibody (TPOAb) positivity, multiple foci, coexistence of PTC, Hashimoto thyroiditis, and increased TSH; they had reduced FT4 and FT3, and reduced BRAF positivity (all P < .05). Logistic regression analysis showed positive correlation between TgAb positivity and multifocality (P < .05). Compared with the noneffective group (88 cases, 16.06%), the effective group (460 cases, 84.94%) had a reduced proportion of TgAb positivity and multifocality, a shorter time interval between surgery and subsequent 131I ablation, and a lower proportion of initial 131I ablation dosage > 100 mCi (all P < .05). Logistic regression showed that TgAb positivity, longer time interval between surgery and subsequent 131I ablation, and initial 131I ablation dosage > 100 mCi were positively correlated with nonefficacy of 131I ablation (odds ratios 2.248, 1.012, and 3.128, respectively; P < .05).

Conclusion: TgAb positivity is associated with increased risk of multiple foci and unfavorable efficacy of 131I ablation in PTC.