Correction to: Dynamics of serum antithyroglobulin antibodies in patients with differentiated thyroid cancer

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Role of 18F-FDG-PET/CT in patients with differentiated thyroid cancer with biochemical incomplete or indeterminate response to treatment

OBJECTIVES

To assess the value of ¹⁸F-FDG-PET/CT for detecting recurrent/persistent disease in patients with biochemical incomplete (BIR) or indeterminate response (IR) and to assess the impact of ¹⁸F-FDG-PET/CT on the therapeutic management of these patients.

METHODS

The study included patients with BIR, in whom ¹⁸F-FDG PET/CT was used within the diagnostic algorithm from our database. Patients with IR referred to our hospital with the ¹⁸F-FDG PET/CT already performed were also enrolled. All patients had neck ultrasonography with no structural changes. A change in therapeutic approach was defined as repeat surgery; administration of external beam radiotherapy; and/or the start of systemic therapy.

RESULTS

Sixty patients (85% women) aged 18-86 years were enrolled in this retrospective study. Of these, 75% had BIR and 25% IR. Increased FDG uptake suggesting locoregional lesions was seen in 40% of patients. Sensitivity, specificity, and diagnostic accuracy of ¹⁸F-FDG PET/CT to detect local disease were 95%, 87.5% and 90% respectively. The therapeutic approach was modified in 50% of patients with locoregional lesions.

CONCLUSIONS

Our study confirmed that ¹⁸F-FDG-PET/CT is a useful tool for detecting locoregional recurrence in thyroid cancer patients with BIR or IR with conflicting findings in standard diagnostic procedures. In 50% of patients with locoregional lesions, there was an immediate change in the treatment approach.

Dynamics of serum antithyroglobulin antibodies in patients with differentiated thyroid cancer

PURPOSE

Serum antithyroglobulin antibodies (sTgAb) affect the reliability of Tg measurement in patients with thyroid cancer. We compared the outcome of patients with detectable and undetectable sTgAb, stratified according to the initial risk of recurrence (RR); also the response to treatment in patients with detectable sTgAb treated with total thyroidectomy (TT) with and without radioiodine remnant ablation (RA) and the sTgAb trend in the long-term follow-up according to the initial response.

METHODS

We included 432 patients submitted to TT, with or without RA; 106 patients had detectable sTgAb levels. Median follow-up was 53 months.

RESULTS

There were no statistically significant differences considering presentation between negative or positive sTgAb subjects. The frequency of structural incomplete response (SIR) in low, intermediate, and high RR was similar. Undetectable sTgAb in patients was achieved in a median of 16 months in ablated patients compared with 11 months in those without RA (p = 0.0232). Patients without RA had a higher rate of undetectable sTgAb during the first 12 months. A SIR was observed in 3% of patients with declining sTgAb, in 19% of those with stable levels, and in 43% with increasing sTgAb (p = 0.004). The status of no evidence of disease was achieved more frequently in patients with initial sTgAb levels < 200 mUI/l, independently of the initial RR.

CONCLUSIONS

There was no impact of sTgAb on the initial clinical presentation and the response to therapy in low-risk patients treated with or without RA. sTgAb trend is more useful than an absolute value to predict a SIR.

The experience of an Endocrinology Division on the use of tyrosine multikinase inhibitor therapy in patients with radioiodine-resistant differentiated thyroid cancer

PURPOSE

To describe the experience of our Division of Endocrinology with multikinase inhibitor (MKI) treatment in radioiodine-resistant differentiated thyroid cancer (DTC) patients.

METHODS

Adults patients with a diagnosis of DTC treated with an MKI drug from March 2011 to October 2018 were registered into a retrospective database. Primary objectives were: the assessment of progression-free survival (PFS) and radiographic response evaluated according to RECIST v. 1.1. Adverse events (AEs) were evaluated by using Common Terminology Criteria for Adverse Events v. 5.0.

RESULTS

Twenty-two patients were treated with MKIs (21 with sorafenib, one with lenvatinib as first-line treatment). Seven patients required a second-line therapy with lenvatinib and one patient required a third-line treatment with pazopanib. Median duration of treatment was 11.2 (4.8-79.6) months. Best responses with sorafenib were partial response (PR) in two patients (11%), stable disease (SD) >6 months in 13 patients (72%), and progressive disease (PD) in three patients (17%). Best responses with second-line lenvatinib were PR in one patient (33%) and SD in two patients (66%). Median PFS was 31.5 months. AEs were present in 19 (90%) patients under sorafenib. The most common AEs were hand-foot syndrome (HFS) (67%), diarrhea (52%), and hypertension (52%). Definitive withdrawal was necessary in only one patient (4.7%).

CONCLUSIONS

Our study reflects the real-world clinical experience of an Endocrinology Division on the management of radioiodine-resistant DTC patients with sorafenib and lenvatinib, showing a beneficial therapeutic effect with acceptable tolerability.