Medullary thyroid nodules by measurement of calcitonin (Ct) in aspiration needle washout in patients with multinodular goiter and moderately elevated serum Ct

The accuracy of fine needle aspiration cytology (FNAC) is low in medullary thyroid carcinomas (MTC). Recently, a few papers analyzed the measurement of calcitonin (Ct) in washout of the needle after aspiration (WO-Ct) suggesting that this approach may be useful in patients with high serum Ct. Here we reported, for the first time in our best knowledge, 3 patients with multinodular goiter, moderately elevated serum Ct, high value of WO-Ct, and medullary outcome. These findings suggest that in presence of high serum Ct, FNAC should be performed in all nodules, and it should be combined with WO-Ct in all cases.     

Risk of Malignancy (ROM) of Thyroid FNA Diagnosed as Suspicious for Malignancy or Malignant: an Institutional Experience with Systematic Review and Meta-Analysis of Literature

A universal recommendation does not exist for thyroid FNA suspicious for malignancy (SFM). In this context, the guidelines have estimated a risk of malignancy (ROM) from 50 to 80% and both total thyroidectomy and lobectomy may be indicated. This study aimed to (1) retrospectively evaluate the SFM (i.e., TIR4) in a single institution to estimate their cancer prevalence at histology, and (2) systematic review the literature to obtain more robust information. The study period was 2015–2018. As a major inclusion criterion, both cytology and histology had to be performed in our institution. Histological diagnosis was the gold standard. For the systematic review, the online databases of Google Scholar, PubMed/MEDLINE, and Scopus were searched for papers using the same classification for thyroid FNA. A proportion meta-analysis was performed to obtain the pooled histological cancer rate among TIR4 and TIR5 (random-effects model). In the institutional database, there were 271 nodules with both histology and FNA and the cancer rate of TIR4 was 88.9%. By systematic review, five studies were selected for the meta-analysis. The pooled cancer rate was 85% in TIR4 and 99% in TIR5 (I2 = 0%; no publication bias). In conclusion, these new findings should prompt the guidelines board to fully revise the estimated ROM of SFM category. Clinical thyroidologists and thyroid surgeons should be aware of these data and the patients with SFM should be informed of their ROM.     

The role of fluorine-18-fluorodeoxyglucose positron emission tomography in evaluating the response to tyrosine-kinase inhibitors in patients with metastatic primary renal cell carcinoma

Background

Positron emission tomography-computed tomography (PET-CT) using fluorodeoxyglucose (FDG) is increasingly used in the evaluation of patients with advanced renal cell carcinoma (RCC), primarily for staging purposes. The aim of this paper is to perform a systematic review about the usefulness of PET-CT using FDG in response assessment after treatment with tyrosine-kinase inhibitors (TKIs) in patients with advanced RCC.

Materials and methods.

The scientific literature about the role of PET-CT using FDG in the assessment of response to treatment with TKIs in patients affected by advanced RCC was systematically reviewed.

Results

Seven studies about the role of PET-CT using FDG in the response assessment after treatment with TKIs (essentially sunitinib and sorafenib) in advanced RCC were retrieved in full-text and analysed, to determine the predictive role of this morpho-functional imaging method on patient outcome.

Conclusions

To date, the role of PET-CT using FDG in evaluating the response to TKIs in metastatic RCC patients is still not well defined, partly due to heterogeneity of available studies; however, PET-CT reveals potential role for the selection of patients undergoing therapy with TKIs. The use of contrast-enhanced PET-CT appears to be promising for a “multi-dimensional” evaluation of treatment response in these patients.     

Thyroid nodules with indeterminate cytology: molecular imaging with 99mTc-methoxyisobutylisonitrile (MIBI) is more cost-effective than the Afirma® gene expression classifier

Purpose

To compare the cost-effectiveness of ^99mTc-methoxyisobutylisonitrile (MIBI) thyroid scintigraphy and the Afirma® gene expression classifier for the assessment of cytologically indeterminate thyroid nodules.

Methods

A decision tree model was used. Costs were calculated from the perspective of the German health insurance system. The robustness of the results was assessed with probabilistic sensitivity analyses using a Monte Carlo simulation.

Results

Life expectancy was 34.3 years (estimated costs per patient €1,459 – €2,224) for the MIBI scan and 34.1 years (estimated costs €3,560 – €4,071) for the molecular test. These results were confirmed by the Monte Carlo simulation.

Conclusion

MIBI thyroid scintigraphy is more cost-effective than the gene expression classifier.     

18F-FDG uptake as a prognostic variable in primary differentiated thyroid cancer incidentally detected by PET/CT: a multicentre study

Purpose

Our aim was to investigate the association between ¹⁸F-fluorodeoxyglucose (FDG) uptake and event-free survival in patients in whom a differentiated thyroid cancer (DTC) was detected by ¹⁸F-FDG positron emission tomography (PET)/CT.

Methods

Among 884 focal ¹⁸F-FDG PET thyroid incidentalomas referred to our 4 Nuclear Medicine Departments, we investigated 54 patients in whom a DTC was confirmed and a clinical follow-up was available. The ratio between maximum standardized uptake value (SUV_max) of DTC and SUV_mean of the liver (SUV ratio) was recorded for each scan. All patients underwent total thyroidectomy and ¹³¹I remnant ablation. After a median follow-up of 39 months we assessed the outcome. The association between disease persistence/progression, ¹⁸F-FDG uptake and other risk factors (T, N, M and histological subtype) was evaluated through univariate and multivariate analyses.

Results

Of the 54 patients, 39 achieved complete remission. The remaining 15 showed persistence/progression of disease. High ¹⁸F-FDG uptake, i.e. SUV ratio ≥3, showed a low positive predictive value (48 %). Low ¹⁸F-FDG uptake (SUV ratio?<?3) displayed a high negative predictive value (93 %). The median of SUV ratios in T1–T2 (2.2), in M0 (2.7) and in non-virulent subtypes (2.7) were significantly lower (p?<?0.03) than in T3–T4 (5.0), M1 (7.3) and virulent subtypes (6.0). Kaplan-Maier analysis showed a significant association between high ¹⁸F-FDG uptake and disease persistence/progression (p?=?0.001). When we adjusted risk estimates by using a multivariate Cox model, only T (p?=?0.05) remained independently associated with disease persistence/progression.

Conclusion

An intense ¹⁸F-FDG uptake of the primary DTC is associated with persistence/progression of disease. However, when all other prognostic factors have been taken into account, ¹⁸F-FDG uptake does not add further prognostic information.     

Ultrasound features of medullary thyroid carcinoma correlate with cancer aggressiveness: a retrospective multicenter study

Background

Poor prognosis of medullary thyroid cancer (MTC) with suspicious ultrasound (US) features has been reported. The aim of the study was to investigate the association between preoperative US presentation and aggressiveness features of MTC. Also, US features of MTC were compared with those previously reported.

Methods

Study group comprised 134 MTC from nine different centers. Based on US presentation the nodules were stratified in “at risk for malignancy” (m-MTC) or “probably benign” (b-MTC) lesions.

Results

Eighty nine (66.4%) m-MTC and 45 (33.6%) b-MTC were found. Metastatic lymph nodes (p = 0.0001) and extrathyroid invasiveness (p < 0.0001) were more frequent in m-MTC. There was statistically significant correlation (p = 0.0002) between advanced TNM stage and m-MTC with an Odds Ratio 5.5 (95% CI 2.1–14.4). Mean postsurgical calcitonin values were 224 ± 64 pg/ml in m-MTC and 51 ± 21 in b-MTC (p = 0.003).

Conclusions

This study showed that sonographically suspicious MTC is frequently associated with features of aggressiveness, suggesting that careful preoperative US of MTC patients may better plan their surgical approach.