Detecting Recurrence Following Lobectomy for Thyroid Cancer: Role of Thyroglobulin and Thyroglobulin Antibodies

Abstract

Background The use of thyroglobulin (Tg) and thyroglobulin antibodies (TgAb) for detecting disease recurrence is well validated following total thyroidectomy and radioiodine ablation. However, limited data are available for patients treated with thyroid lobectomy. Methods Patients who had lobectomy for papillary thyroid cancer followed for >1 year, with sufficient data on Tg and TgAb, including subgroup analysis for Hashimoto’s thyroiditis and contralateral nodules. Results One-hundred sixty-seven patients met the inclusion criteria. Average tumor size was 9.5 ± 6 mm. Following lobectomy, Tg was 12.1 ± 14.8 ng/mL. Of 52 patients with Hashimoto’s thyroiditis, 38% had positive TgAb with titers of 438 ± 528 IU/mL, and in patients without TgAb the mean Tg level was 14.7 ± 19.0 ng/mL. In 34 patients with contralateral nodules ≥1 cm, Tg was 15.3 ± 17 ng/mL. During the first 2 years of follow-up, Tg declined ≥1 ng/mL in 42% of patients (by 5.1 ± 3.7 ng/mL), remained stable in 22%, and increased in 36% (by 4.9 ± 5.7 ng/mL). During a mean follow-up of 6.5 years (78 ± 43.5 months), 18 patients had completion thyroidectomy and 12 were diagnosed with contralateral cancer (n = 8) or lymph node metastases (n = 4). In patients with recurrence followed for >2 years, there was a rise in Tg in 3 cases, Tg was stable in 2 cases, and in 1 TgAb decreased from 1534 to 276 IU/mL despite metastatic lymph nodes. Basal Tg and Tg dynamics did not predict disease recurrence. Conclusions Serum thyroglobulin used independently is of limited value for predicting or detecting disease recurrence following thyroid lobectomy. Other potential roles of Tg, such as detecting distant metastases following lobectomy, should be further studied.

Annual Hazard Rate of Recurrence in Middle Eastern Papillary Thyroid Cancer over a Long-Term Follow-Up

“…Thyroid cancer is the most common endocrine cancer, and its incidence is increasing worldwide [1,2]. Nearly 20% of papillary thyroid cancer (PTC) patients who have no evidence of disease after initial treatment present with recurrence of disease during subsequent follow-up [3][4][5][6]. Although most recurrences in PTC are not fatal, they can be a great burden for patients, especially in a population with a high incidence rate for PTC, like Saudi Arabia [7].…”

Thyroid Lobectomy for Low to Intermediate Risk Differentiated Thyroid Cancer

“…In fact, patients without recurrence were more likely to have Tg increase >20% over time. Another cohort study of 167 patients also observed a gradual increase in Tg levels over time [60]. In the absence of anti-Tg antibodies, average postoperative Tg levels were 14.7 ± 19.0 ng/mL.…”

“…A further systematic review of 31 studies and 228,746 patients found that recurrence rates after thyroid lobectomy were slightly but significantly higher than after total thyroidectomy: 9% versus 7.4%, p = 0.001) [59]. Cancer recurrence in the contralateral lobe was observed in 4.8% of patients in the retrospective study by Ritter et al of 167 patients followed for an average of 6.5 years [60], with an additional 2.4% of patients with recurring lymph node metastases. Matsuzu et al reported a 6.5% rate of recurrence in the remaining thyroid and a 9.4% rate of recurrence in regional lymph nodes in 1088 patients followed for 25 years [38].…”

Advancements in the treatment of differentiated thyroid cancer

“… 77 However, the utility of these thresholds in appropriately stratifying patients after lobectomy has been challenged. 78 , 79 Further investigation is therefore needed to better define response criteria for patients treated with lobectomy.…”