Is Stimulated Thyroglobulin Necessary after Ablation in All Patients with Papillary Thyroid Carcinoma and Basal Thyroglobulin Detectable by a Second-Generation Assay?
Objective. To evaluate the percentage of elevated stimulated thyroglobulin (sTg) and persistent or recurrent disease (PRD) in patients with detectable basal Tg < 0.3 ng/mL. Methods. The sample consisted of 130 patients with papillary thyroid carcinoma (PTC) who were at low risk of PRD and who had neck ultrasound (US) without abnormalities, negative anti-Tg antibodies (TgAb), and detectable basal Tg < 0.3 ng/mL about 6 months after ablation. Results. sTg was <1 ng/mL in 88 patients (67.7%), between 1 and 2 ng/mL in 26 (20%), and ≥2 ng/mL in 16 (12.3%). Imaging methods revealed the absence of tumors in 16 patients with elevated sTg. During follow-up, Tg increased to 0.58 ng/mL in one patient and lymph node metastases were detected. Sixty-nine patients continued to have detectable Tg < 0.3 ng/mL and US revealed recurrence in only one patient. Sixty patients progressed to persistently undetectable Tg without apparent disease on US. Conclusions. In low-risk patients with PTC who have detectable basal Tg < 0.3 ng/mL after ablation, negative TgAb, and US, persistent disease is rare and eventual recurrences can be detected by basal Tg elevation and/or subsequent US assessments, with follow-up without sTg being an "alternative" to Tg stimulation.
Postgraduate Program, Santa Casa de Belo Horizonte, 590 Domingos Vieira Street, 30150340 Belo Horizonte, MG, Brazil ; Endocrinology Service, Santa Casa de Belo Horizonte, 1111 Francisco Sales Avenue, 30150221 Belo Horizonte, MG, Brazil.
Pedro Weslley
PW
Rosario
Postgraduate Program, Santa Casa de Belo Horizonte, 590 Domingos Vieira Street, 30150340 Belo Horizonte, MG, Brazil ; Endocrinology Service, Santa Casa de Belo Horizonte, 1111 Francisco Sales Avenue, 30150221 Belo Horizonte, MG, Brazil.
Gabriela
G
Franco Mourão
Endocrinology Service, Santa Casa de Belo Horizonte, 1111 Francisco Sales Avenue, 30150221 Belo Horizonte, MG, Brazil.
Maria Regina
MR
Calsolari