Prognostic value of postoperative stimulated thyroglobulin levels on 131Ⅰ ablation therapy in papillary thyroid cancer

Objective Stimulated thyroglobulin (Tg) levels postablation was associated with disease recurrence in papillary thyroid cancer (PTC). The aim of this study was to evaluate the prognostic value of postoperative stimulated Tg level on future Tg positivity after 131Ⅰ ablation therapy in PTC. Methods One hundred and thirty-eight patients (28 men, 110 women; age range 6-70 years, mean age 39.4 years) with PTC were included in this study. All patients underwent total or near-total thyroidectomy, and 102 of these patients had lymphadenectomy. All patients had a documented PTC. 131Ⅰ ablation was performed in 3- 4 weeks after thyroidectomy. Sera levels of thyroid hormones (FT3, FT4), thyrotropin (TSH), anti-Tg anti-body (TgAb), and Tg were measured before and after 131Ⅰ ablation. Statistical analysis was performed with SPSS 13.0 software, and correlation anaysis and t-test were used. Results Postoperative stimulated Tg lev-el had a significantly positive association with pestablation stimulated Tg level (r = 0. 960, P < 0.01). Postoperative stimulated Tg level in positive postablation Tg group was significantly higher than that in nega-tive pestablation Tg group (199.8±327.7) μg/L vs (3.5±5.6) μg/L, t =5. 567, P <0.01]. About 76% (78/102) patients had evidence of metastatic cervical lymph nodes on routine histological testing. And 41% (446/1088) resected lymph nodes were histologically positive for metastatic disease. The number of metastatic lymph nodes resected had a significantly positive relationship with stimulated Tg at pestopera-tion and postablation (r = 0. 697, 0. 633, both P < 0.01). Conclusions Postoperative stimulated Tg level was of better prognostic value on stimulated Tg level after 131Ⅰ ablation therapy. Total or near-total thyroidec-tomy simultaneously conjugated with lymphadenectomy might have a better result in lower postablation stimu-lated Tg pesitivity in patients with PTC.