Time Of Remnant Ablation Research Articles

Only peak thyroglobulin concentration on day 1 and 3 of rhTSH-aided RAI adjuvant treatment has prognostic implications in differentiated thyroid cancer

ObjectiveIn patients with differentiated thyroid carcinoma (DTC), serum thyroglobulin levels measured at the time of remnant ablation after thyroid hormone withdrawal were shown to have prognostic value for disease-free status. We sought to evaluate serial thyroglobulin measurements at the time of recombinant human thyroid-stimulating hormone (rhTSH)-aided iodine 131 (131I) adjuvant treatment as prognostic markers of DTC.MethodsSix hundred-fifty patients with DTC given total/near-total thyroidectomy and adjuvant radioiodine post-rhTSH stimulation were evaluated. Thyroglobulin was measured on day 1 (Tg1; at the time of the first rhTSH injection), day 3 (Tg3; 1 day after the second, final rhTSH injection), and day 6 (Tg6; 3 days post-radioiodine administration). Treatment failure was defined as histopathologically confirmed locoregional recurrence, or radiologically-evident distant metastases (signs of disease on computer tomography (CT) or magnetic resonance imaging (MRI), or abnormal foci of radioiodine or [18F] fluorodeoxyglucose ([18F]FDG) uptake.ResultsIn univariate analysis, Tg1 (p < 0.001) and Tg3 (p < 0.001), but not Tg6, were significantly associated with structural recurrence. In multivariate analysis of the overall cohort, only Tg3 was independently associated with structural recurrence. In multivariate analysis of the subgroup (n = 561) with anti-Tg antibodies titers below the institutional cut-off, 115 IU/mL, Tg1 was an independent prognostic marker. Tg1 and Tg3 cutoffs to best predict structural recurrence were established at 0.7 ng/mL and 1.4 ng/mL, respectively.ConclusionsTg1 and Tg3, measurements made after rhTSH stimulation but before radioiodine treatment, independently predict a low risk of treatment failure in patients with DTC. Levels measured post-radioiodine application (e.g., Tg6) are highly variable, lack prognostic value, and hence can be omitted.

BRAF V600E Status and Stimulated Thyroglobulin at Ablation Time Increase Prognostic Value of American Thyroid Association Classification Systems for Persistent Disease in Differentiated Thyroid Carcinoma.

Background Stimulated thyroglobulin levels measured at the time of remnant ablation (A-hTg) and BRAFV600E mutation had shown prognostic value in predicting persistent disease in differentiated thyroid cancer (DTC). The aim of this study was to evaluate the prognostic role of A-hTg combined with the BRAFV600E status in association with the revised American Thyroid Association (ATA) risk stratification. Material and Methods 620 patients treated for a DTC were included in this study with a median follow-up duration of 6.1 years. All patients underwent total thyroidectomy followed by radioiodine ablation. Patients with positive anti-thyroglobulin antibodies were excluded. The predictive value of A-hTg was calculated by receiver operating characteristic curve (ROC curve) analysis. The Cox proportional hazard regression model, including the BRAF status, A-hTg, and ATA classification system, was assessed to evaluate the existing persistent disease risk. Results Taken together, the BRAF status and A-hTg levels improve the ATA risk classification in all categories. In particular, in the low-risk ATA classification, only the combination of BRAFV600E+A-hTg > 8.9ng/ml was associated with persistent disease (P = 0.001, HR 60.2, CI 95% 5.28-687). In the intermediate-risk ATA classification, BRAFWT+A-hTg > 8.9ng/ml was associated with persistent disease (P = 0.029, HR 2.71, CI 95% 1.106-6.670) and BRAFV600E+A-hTg > 8.9ng/ml was also associated with persistent disease (P < 0.001, HR 5.001, CI 95% 2.318-10.790). In the high-risk ATA classification, both BRAFV600E+A-hTg < 8.9ng/ml and BRAFV600E+A-hTg > 8.9 ng/ml were associated with persistent disease (P = 0.042, HR 5.963, CI 95% 1.069-33.255 and P = 0.002, HR 11.564, CI 95% 2.543-52.576, respectively). Conclusions The BRAF status and stimulated thyroglobulin levels at ablation time improve the ATA risk stratification of differentiated thyroid cancer; therefore, even A-hTg could be included in risk classification factors.

Is a second recombinant human thyrotropin stimulation test useful? The value of postsurgical undetectable stimulated thyroglobulin level at the time of remnant ablation on clinical outcome

The management of patients with differentiated thyroid cancer (DTC) has changed in recent years, and monitoring depends on the risk of persistent/recurrent disease. The objective was to assess the prognostic value of a single stimulated thyroglobulin (Tg) measured at the time of the first radioiodine therapy (Stim-Tg1), and the utility of a second stimulated Tg measurement performed 6-12months later (Stim-Tg2). We also examined the role of neck ultrasound (US) in the early diagnosis of recurrence. This was a retrospective observational cohort study conducted in a tertiary referral hospital. Of 213 evaluated patients with DTC, 169 were finally included. Measurement of Stim-Tg1, Stim-Tg2 and neck US. Stim-Tg1 was undetectable in 71 of 169 patients (42%). All of them (71/71) continued to have negative Stim-Tg2. Seventy of 71 had an excellent response to the first treatment. Sixty-eight of 71 had no evidence of disease after an average follow-up of 7·2years. In patients with detectable Stim-Tg1 (98/169; 58%), Stim-Tg2 became negative in 40. The negative predictive value (NPV) of Stim-Tg1 was 0·96. The optimal Stim-Tg1 cut-off level for identifying persistence was 3·65ng/ml. Recurrence was detected in 14 patients. Neck US was useful for identifying local recurrence (13/14; 92·85%). Stim-Tg1 is a reliable marker with a high NPV. A second stimulation test should be avoided in patients with negative Stim-Tg1. In patients with biochemical persistence, Stim-Tg2 is useful for confirming/ruling out final status. Neck US plays a valuable role in the early diagnosis of recurrence.

Surgical outcomes of robotic thyroid surgery using a double incision gasless transaxillary approach: Analysis of 400 cases treated by the same surgeon

The purpose of this study was to evaluate the surgical outcomes of 400 cases of robotic thyroid surgery using a double incision gasless transaxillary approach. We analyzed 400 patients who underwent a robot-assisted thyroidectomy performed by a single surgeon. All patients underwent successful operations without conversion to open surgery. Transient hypoparathyroidism was the most common complication (51.7%) and permanent hypoparathyroidism occurred in only 2 patients (1.4%). The mean number of retrieved central lymph nodes was 6.5 ± 4.4 for ipsilateral central compartment node dissection and 8.4 ± 5.1 for bilateral central compartment node dissection. The proportion of patients with stimulated thyroglobulin (sTg) levels at the time of remnant ablation <10 ng/mL and sTg levels 6 to 12 months after the first ablation <1 ng/mL was 84.9% and 88.3%, respectively. Robotic thyroid surgery is technically safe and may be a surgical option for patients with well-differentiated thyroid cancer.

Low thyroglobulin concentrations after thyroidectomy increase the prognostic value of undetectable thyroglobulin levels on levo-thyroxine suppressive treatment in low-risk differentiated thyroid cancer

Recombinant human TSH-stimulated thyroglobulin (Tg) levels (rhTSH-Tg) are sufficient for early follow-up of low-risk differentiated thyroid cancer (DTC) patients after thyroidectomy and radioiodine (131I) remnant ablation (RAI). Serum Tg levels at the time of remnant ablation (ablation-Tg) is thought to be related with rhTSH-Tg and may be predictive of recurrent disease. During long-term follow-up, Tg levels on levo-T4 (L-T4) suppressive treatment (suppressive-Tg) is sufficiently sensitive to avoid further evaluations in patients with undetectable rhTSH-Tg. The aim of our study was to verify whether, in a subgroup of low-risk DTC patients, the association of low ablation-Tg levels (<10 microg/l) with undetectable suppressive-Tg concentrations has a sufficient negative predictive value (NPV) for recurrence of disease, leading to avoid rhTSH testing. We enrolled 169 low-risk DTC patients treated by thyroidectomy + RAI and undetectable suppressive-Tg at 12-month followup. In all patients, we retrospectively evaluated ablation-Tg and rhTSH-Tg. For all patients, 2-yr follow-up was available. Based on rhTSH-Tg>2 microg/l, relapsing disease was histologically proven in 2 patients. rhTSH-Tg levels between 0.6-2.0 microg/l, with no evidence of disease, was observed in 10 patients (6%). One hundred and fifty-seven patients showed undetectable rhTSH-Tg. The NPV of undetectable suppressive- Tg was 92.8%. The ablation-Tg level was <10 microg/l in 140 patients. In this group, the NPV of undetectable suppressive- Tg was 100%. Our data indicate that undetectable suppressive-Tg value, combined with ablation- Tg levels <10 microg/l, may avoid a significant number of high-cost rhTSH-Tg test.

Change of Serum Antithyroglobulin Antibody Levels Is Useful for Prediction of Clinical Recurrence in Thyroglobulin-Negative Patients with Differentiated Thyroid Carcinoma

The aim of the study was to evaluate the usefulness of the antithyroglobulin autoantibody (TgAb) value at 6-12 months after remnant ablation in predicting recurrence in differentiated thyroid carcinoma patients who had undetectable thyroglobulin (Tg) values. The change in TgAb concentration measured between the time of remnant ablation (TgAb1) and 6-12 months thereafter (TgAb2) was also evaluated as a possible prognostic indicator. Patients with differentiated thyroid carcinoma who underwent total thyroidectomy followed by (131)I remnant ablation between 1995 and 2003 at the Asan Medical Center (Seoul, Korea) were enrolled. Of these, 824 patients with undetectable Tg at 6-12 months after remnant ablation during thyroid hormone withdrawal were the subjects of this study. TgAb2 was positive in 56 patients. Ten of 56 patients (18%) with positive TgAb2 had recurrence, whereas only 10 of 768 patients (1%) with negative TgAb2 had recurrence during 73.6 months of follow-up (P < 0.001). The change between TgAb1 and TgAb2 levels was evaluated in patients with positive TgAb2. TgAb concentration decreased by more than 50% in 21 patients (group 1) and by less than 50% in 16 patients (group 2), and it increased in 19 patients (group 3). The recurrence rates in groups 1, 2, and 3 were 0, 19, and 37%, respectively (P = 0.016). Serum TgAb levels measured at 6-12 months after remnant ablation could predict recurrence in patients with undetectable Tg values. In patients with undetectable Tg and positive TgAb values, a change in TgAb concentration during the early postoperative period may be a prognostic indicator of recurrence.

Serum Thyroglobulin Levels at the Time of131I Remnant Ablation Just after Thyroidectomy Are Useful for Early Prediction of Clinical Recurrence in Low-Risk Patients with Differentiated Thyroid Carcinoma

We investigated whether serum thyroglobulin (Tg) measured at the time of remnant ablation (ablation-Tg) could be a prognostic indicator complementary to serum Tg levels at the time of the first diagnostic whole-body scan (WBS) after thyroid hormone withdrawal (control-Tg; approximately 6-12 months after ablation-Tg) and whether ablation-Tg could predict the persistence or recurrence of disease in low-risk patients with differentiated thyroid carcinoma. Patients with differentiated thyroid carcinoma (n = 268) treated with total or near-total thyroidectomy followed by immediate (131)I remnant ablation were studied. Patients with anti-Tg autoantibodies and those showing evidence of extracervical metastases were excluded. Two patients showing remnant uptake on follow-up diagnostic WBS received a second ablation. We found significant correlation between ablation-Tg and control-Tg levels; 114 of 143 patients (80%) with ablation-Tg greater than 2 microg/liter showed detectable (>/=1 microg/liter) control-Tg, and 70 of 125 (56%) patients with ablation-Tg 2 microg/liter or less showed undetectable (<1 microg/liter) control-Tg [odds ratio 5.1, 95% confidence interval (CI) 3.0-8.9, P < 0.001]. When the 268 patients were followed up for a mean period of 5.7 +/- 1.4 yr (range 2.8-8.3 yr), 35 (13%) had recurrences; 73 (27%) were classified as "Tg positive, no evidence of disease"; and 160 (60%) showed complete remission. Of 143 patients with ablation-Tg greater than 2 microg/liter, recurrence was observed in 33 cases (23%); "Tg positive, no evidence of disease," was observed in 52 cases (36%); and complete remission was observed in 58 cases (41%). Of 125 patients with ablation-Tg 2 microg/liter or less, two patients (2%) showed recurrence during the follow-up; 21 patients (17%) were regarded as "Tg positive, no evidence of disease"; and 102 patients (81%) showed complete remission. The positive predictive value for recurrence in patients having ablation-Tg greater than 2 microg/liter was found to be 23.1% (33 of 143 patients, 95% CI 16.4-30.8%). The negative predictive value for recurrence in patients having ablation-Tg 2 microg/liter or less was found to be 98.4% (123 of 125 patients, 95% CI 94.4-99.8%). These data indicate that serum Tg levels measured at the time of immediate postoperative (131)I remnant ablation correlated well with serum Tg levels at the time of the initial diagnostic WBS and had a complementary role for predicting persistence or recurrence of disease in the earliest postoperative period.