Intermediate-risk Differentiated Thyroid Cancer Research Articles

Post-surgical thyroid ablation with low or high radioiodine activities results in similar outcomes in intermediate risk differentiated thyroid cancer patients

In differentiated thyroid cancer (DTC) patients at intermediate risk of recurrences, no evidences are provided regarding the optimal radioactive iodine (RAI) activity to be administered for post-surgical thyroid ablation. This study aimed to evaluate the impact of RAI activities on the outcome of 225 DTC patients classified as intermediate risk, treated with low (1110-1850 MBq) or high RAI activities (≥3700 MBq). Six to 18 months after ablation, remission was observed in 60.0% of patients treated with low and in 60.0% of those treated with high RAI activities, biochemical disease was found in 18.8% of patients treated with low and in 14.3% of patients treated with high RAI activities, metastatic disease was found in 21.2% of patients treated with low and in 25.7% of patients treated with high RAI activities (P=0.56). At the last follow-up (low activities, median 4.2 years; high activities, median 6.9 years), remission was observed in 76.5% of patients treated with low and in 72.1% of patients treated with high RAI activities, persistent disease was observed in 18.8% of patients treated with low and in 23.5% of patients treated with high RAI activities, recurrent disease was 2.4% in patients treated with low and 2.1% in patients treated with high RAI activities, deaths occurred in 2.4% of patients treated with low and in 2.1% of patients treated with high RAI activities (P=0.87). Our study provides the first evidence that in DTC patients at intermediate risk, high RAI activities at ablation have no major advantage over low activities.

A Low Postoperative Nonstimulated Serum Thyroglobulin Level Does Not Exclude the Presence of Radioactive Iodine Avid Metastatic Foci in Intermediate-Risk Differentiated Thyroid Cancer Patients

Postsurgical thyrotropin (TSH)-stimulated serum thyroglobulin (Tg) level can be used to predict the likelihood of finding radioactive iodine (RAI) avid metastatic foci on postablation scanning. However, there is little data regarding the predictive value of a nonstimulated postoperative Tg obtained on levothyroxine therapy in patients being considered for recombinant human TSH (rhTSH)-assisted remnant ablation. The study included 290 intermediate-risk differentiated thyroid cancer (DTC) patients with a postsurgical nonstimulated Tg<10 ng/mL prior to rhTSH-assisted remnant ablation. Patients were stratified into four groups based on the postsurgical nonstimulated Tg value: Tg<0.6 ng/mL (n=146), Tg 0.6-0.9 ng/mL (n=76), Tg 1-5 ng/mL (n=51), and Tg>5-10 ng/mL (n=17). RAI avid metastatic foci were identified using post-therapy scanning with SPECT/CT (single photon emission computed tomography). RAI avid metastases were identified in 16% (46/290) of patients, including 12% (17/146) with Tg<0.6 ng/mL, 14% (11/76) with Tg 0.6-0.9 ng/mL, 25% (13/51) with Tg 1-5 ng/mL, and 29% (5/17) with Tg>5-10 ng/mL (p=0.02). While 99% of the RAI avid foci were located in the neck, lung uptake was seen in one patient with Tg<0.6 ng/mL (0.7%, 1/146), one patient with Tg 0.6-0.9 ng/mL (1.3%, 1/76), and 2 patients with Tg>5-10 ng/mL (11%, 2/17 patients). A postoperative nonstimulated Tg<0.6 ng/mL does not exclude identification of RAI avid metastatic foci on postablation SPECT/CT scanning in intermediate-risk DTC patients. Therefore, patient selection for RAI ablation in the intermediate-risk group must be based on an integration of multiple risk factors rather than any single clinicopathologic risk factor.

Minimally invasive video-assisted thyroidectomy: an analysis of results and a revision of indications

The first report of minimally invasive video-assisted thyroidectomy (MIVAT) was published in 1999, and the indications were progressively implemented: from cytologically undetermined thyroid nodules to intermediate-risk differentiated thyroid cancers. The aim of this study was to review the entire series of patients who underwent a MIVAT, critically analyzing its indications and contraindications and trying to figure out how the indications might be extended. From 1998 to 2009, a total of 1,946 patients (1,659 females, 287 males; mean age = 40.2 years) underwent MIVAT in our department. Inclusion criteria were benign thyroid nodules <35 mm, malignant nodules <20 mm, and an ultrasonographically estimated thyroid volume (ETV) <25 cc. The presence of suspicious or metastatic lymph nodes and the presence of severe thyroiditis were considered a contraindication for MIVAT. A total thyroidectomy was performed in 1,435 patients (72.3%). A total lobectomy was performed in 511 cases (26.3%), and a central neck node sampling was associated with total thyroidectomy in 104 cases. Final histology revealed benign disease in 979 cases (51.5%) and a malignancy was diagnosed in 915 cases (48.5%). Unexpected thyroiditis was found on final histology in 17.9% of the patients with benign disease and 30.9% of patients with malignancy. The incidence of thyroiditis was significantly different in these two populations (p < 0.0001). Our data confirm the validity of the traditional indications for MIVAT: low-risk differentiated thyroid cancer (DTC), cytologically undetermined nodules, and small-volume benign thyroid disease. The indications may be further and safely extended to those patients with associated thyroiditis and those with intermediate-risk DTC. MIVAT can be proposed on a much larger scale than it was at its onset and cannot be considered an option for only a limited number of patients.