The usefulness of detecting thyroglobulin in fine-needle aspirates from patients with neck lesions using a sensitive thyroglobulin assay

Cut-off Value for Thyroglobulin Washout Concentration in the Detection of Cervical Lymph Node Metastases in Patients after Thyroidectomy Due to Differentiated Thyroid Cancer

The aim of this study was to establish the cut-off value for the thyroglobulin (Tg) concentration in washout fluid from fine needle aspiration biopsy (FNA-Tg) in the detection of cervical lymph node metastases of differentiated thyroid cancer (DTC). We evaluated the validity and clinical utility of fine needle aspiration biopsy cytology (FNAB-C), FNA-Tg, and the combined method in detecting DTC recurrences. The study included 82 patients after the total thyroidectomy and elective and, in some cases, also selective cervical lymphadenectomy. The majority of patients also underwent subsequent 131I ablative therapy. The patients presented with 1-6 enlarged and/or ultrasonographically suspicious cervical lymph nodes. One to four aspirates of each lymph node were taken, with a total of 297 samples. An FNA-Tg of 4.34 ng/mL was established as the cut-off value for detecting cervical lymph node DTC metastases for the IRMA Brahms DYNO test, Tg-S. FNAB-C is highly specific (91-99%) but not sensitive enough (53-69%) to be used as a standalone method in the detection of cervical lymph node metastases. FNA-Tg is more sensitive (91%), but caution should be taken when selecting patients for surgery with an FNA-Tg higher than the established cut-off value but lower than the serum Tg concentration. To select patients for lymphadenectomy, we recommend using the combined method (FNAB-C and FNA-Tg) with a sensitivity of 96% and specificity of up to 97%. More than one sample should be taken with each fine needle aspiration biopsy (FNAB) to obtain a representative set of samples.

The effectiveness of the method for determining the level of thyroglobulin in needle washouts of fine-needle aspiration biopsy in the differential diagnosis of metastases of highly differentiated thyroid cancer in the lymph nodes of the neck

Introduction. Thyroid cancer is one of the most common malignant neoplasms of the endocrine system. well-differentiated thyroid cancer constitutes about 90 % of all malignant tumors of the thyroid gland. Despite growing morbidity and high incidence of this pathology, in case of timely diagnosis and treatment well-differentiated thyroid cancer has favorable prognosis.

Aim. using clinical examples, to demonstrate the possibility of thyroglobulin measurement in needle washouts of fineneedle aspiration biopsy in the detection of cervical metastases of highly differentiated thyroid cancer.

Materials and methods. five patients (2 patients with combined oncological pathology, 2 patients with nodes in the thyroid gland, 1 patient after a thyroidectomy) with cervical adenopathy measured the level of thyroglobulin in the wash out fluid of lymph-nodes biopsy using the immunoradiometric method using the commercial kits of the Institute of Isotopes-IRmA (Hungary).

Results. Cervical metastases of highly differentiated thyroid cancer were detected or excluded by the determination of fine-needle aspiration biopsy in patients with non-informational cytological studies. The determination of fineneedle aspiration biopsy is a useful diagnostic method in the differential diagnosis of cervical metastases in patients who have other morphological forms of cancer in addition to well-differentiated thyroid cancer, as well as for the differential diagnosis of cervical adenopathy in patients with a history of highly differentiated thyroid cancer.

Conclusion. Determination of thyroglobulin level in puncture needle washout is a simple and useful diagnostic method for differential diagnosis of metastases in lymph nodes of the neck in patients with several morphological forms of malignant tumors.

Long-Term Efficacy of Ethanol Ablation as Treatment of Metastatic Lymph Nodes From Papillary Thyroid Carcinoma

CONTEXT

Ethanol ablation (EA) is considered an alternative to surgery for metastatic lymph nodes from papillary thyroid carcinoma (PTC) in selected patients.

OBJECTIVE

The aim of this study was to evaluate the long-term efficacy and safety of this treatment.

DESIGN AND SETTING

Adult patients with PTC who had received EA in lymph node metastasis at a tertiary referral center, and were included in a published study from 2011, were invited to participate in this follow-up study.

METHODS

Radiologic and medical history were reviewed. Ultrasound examination of the neck was performed by radiologists, and clinical examination was performed by an endocrine surgeon. Response was reported according to predefined criteria for satisfactory EA treatment. Adverse events associated with EA were evaluated. Cause of death was reported for deceased patients.

RESULTS

From the 2011 study, 51 of 63 patients were included. Forty-four patients were reexamined (67/109 lesions) and 7 patients were deceased. Median follow-up time from primary surgery was 14.5 years. Median follow-up from the latest performed EA in the 2011 study was 11.3 years. Local control was permanently achieved in most patients (80%). Recurrence within an ablated node was registered in 13 metastases in 10 patients. Seven of these patients also had recurrent disease elsewhere in the neck. No major side effects were reported.

CONCLUSION

EA is a minimally invasive procedure with a low risk of complications. Our data suggest that EA is a safe and efficient treatment, providing excellent results for a large group of patients in the long term.

Diagnostic strategy of fine needle aspiration cytology of cystic cervical lymph node metastasis from papillary thyroid carcinoma

BACKGROUND

Cystic cervical lymph node metastasis from papillary thyroid carcinoma (CLMPTC) initially presents as cervical cystic lesions, which are often underdiagnosed as other cystic cervical lesions. There is no comprehensive diagnostic strategy of fine needle aspiration (FNA) cytology for CLMPTC.

METHODS

The clinical and FNA cytomorphology data of 87 patients with CLMPTC were analyzed. Thyroglobulin (TG) immunostaining was performed in 40 cases; BRAF V600E mutation was evaluated in 42 cases; the thyroglobulin (Tg) levels of aspiration fluids were assessed in 46 cases. Correspondingly, the data of 42 cases with solid cervical lymph node metastasis from papillary thyroid carcinoma (SLMPTC) and 32 cases with other cystic cervical lesions were collected as controls.

RESULTS

Compared with SLMPTC, CLMPTC has less classical PTC cytomorphology characteristics-for example, nuclear crowding/overlapping, nuclear irregular contours, etc. (p < .05). Additionally, micropapillary architecture and histiocyte-like tumor cells were more often observed in CLMPTC than in SLMPTC (p < .01). The positive rate of TG immunocytochemistry in CLMPTC was 100% (40/40). The positive rate of BRAF V600E mutation in CLMPTC was 81.0% (34/42), which was higher than that in SLMPTC (64.3%; 27/42) (p = .087). The Tg levels in aspiration fluids were significantly higher in CLMPTC (all>500 μg/L) than in other cervical cystic lesions (range: 2.9 μg/L to 40.1 μg/L) (p < .01).

CONCLUSION

To reduce underdiagnoses of CLMPTC, a reasonable diagnostic strategy, as summarized in this study is needed: according to the number of tumor cells, choosing immunocytochemistry (TG) and/or thyroglobulin in fine needle aspirates testing as auxiliary diagnostic measures.

The influence of thyroid status, serum Tg, TSH, and TgAb on FNA-Tg in cervical metastatic lymph nodes of papillary thyroid carcinoma

OBJECTIVE

Papillary thyroid carcinoma is treated in China mostly with surgery, including total ablation, lobectomy, and lobe and isthmus resection. Therefore, whether thyroid status affects the FNA-Tg cutoff value in the diagnosis of cervical lymph node metastasis deserves our attention. In addition, we investigated the influence of serum Tg, TSH, and TgAb on the accuracy of using FNA-Tg for diagnosis.

METHODS

Our retrospective analysis included 189 suspected cervical lymph nodes, and we determined whether the cutoff value of FNA-Tg was affected by thyroid status, sTg, sTSH, and sTgAb.

RESULTS

In thyroid present cases, the optimal cutoff value of FNA-Tg was 2.3 ng/ml (sensitivity 96.2%, specificity 100%), and in the thyroid absent cases, the optimal cutoff value of FNA-Tg was 0.7 ng/ml (sensitivity 97.6%, specificity 96.0%). Although serum Tg, TSH, and TgAb were weakly correlated with FNA-Tg values, they did not affect the diagnostic performance of the optimal cutoff value of FNA-Tg according to thyroid status.

CONCLUSIONS

The optimal cutoff value of FNA-Tg should be selected according to the thyroid status (2.3 ng/ml for thyroid present cases and 0.7 ng/ml for thyroid absent cases) to ensure the efficient diagnosis of cervical metastatic lymph nodes of papillary thyroid carcinoma. It was determined that sTg, sTSH, and sTg-Ab cannot influence the diagnostic performance of FNA-Tg. The combination method of FNA-Tg and FNAC is the most optimal choice for the diagnosis of lymph nodes metastasis.

The diagnostic value of thyroglobulin in fine-needle aspiration of metastatic lymph nodes in patients with papillary thyroid cancer and its influential factors

Thyroglobulin (Tg) measurement in fine-needle aspiration (FNA-Tg) has proved to be an excellent tool to identify metastatic cervical lymph nodes (CLN) before or after surgery for papillary thyroid cancer (PTC). The diagnostic value of FNA-Tg for metastatic CLN in PTC patients is higher than that of ultrasound (US) and fine-needle aspiration cytology (FNAC), especially for small or cystic LN. The combination of FNAC and FNA-Tg can provide nearly 100% diagnostic sensitivity and specificity for CLN metastasis. However, the cutoff values of FNA-Tg for metastatic CLN have not been standardized, and the reported cutoff values of FNA-Tg range from 0.2 ng/ml to 77 ng/ml because of the differences in study samples, Tg measurement methods, Tg assays kits, etc. Serum anti-thyroglobulin antibody level, serum thyroglobulin level, the presence or absence of thyroid glands, and the characteristics of CLN may be factors affecting the accuracy of FNA-Tg. This review summarizes the recent research on the application of FNA-Tg in the diagnosis of metastatic LN in PTC and provides a reliable basis for the clinical diagnosis of cervical lymph node metastasis.

Thyroglobulin Measurement Through Fine-Needle Aspiration for Optimizing Neck Node Dissection in Papillary Thyroid Cancer

BACKGROUND

Thyroglobulin measurement in fine-needle aspiration (FNA-Tg) is an additional diagnostic tool of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC). However, its performance as a preoperative indicator of lateral neck LNM in PTC is unclear. We evaluated the use of FNA cytology and FNA-Tg to detect neck LNM presurgery using a simple methodology, and established a cut-off value for diagnosing LNM in PTC.

METHODS

We performed a retrospective cohort study based on hospital records, including 299 FNA-Tg measurements from 228 patients with PTC. The cut-off value for FNA-Tg was obtained through a receiver operating characteristic (ROC) curve analysis. The relationships between various parameters and FNA-Tg were analyzed using Spearman's correlation.

RESULTS

Of 299 lymph nodes (LNs) from 228 patients following surgery, 151 were malignant and 148 were benign. The median FNA-Tg levels were 414.40 ng/mL and 6.36 ng/mL in the metastatic and benign LNs, respectively. An FNA-Tg cut-off value of 28.3 ng/mL had the best diagnostic performance (93.38% sensitivity, 70.27% specificity, area under the ROC curve [AUC] 0.868) in the whole cohort. The diagnostic value performed better in the lateral neck group (level II-V, n = 163) than in the central neck group (level VI, n = 136); in the lateral neck group, the sensitivity and specificity of the FNA-Tg cut-off (16.8 ng/mL) were 96.25% and 96.36%, respectively.

CONCLUSIONS

FNA-Tg is a useful technique for the diagnosis of LNM before surgery, especially in lateral neck dissection.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR1900028547.

Fine Needle Biopsy Versus Core Needle Biopsy Combined With/Without Thyroglobulin or BRAF 600E Mutation Assessment for Detecting Cervical Nodal Metastasis of Papillary Thyroid Carcinoma

Objectives

To analyze the diagnostic benefit of fine needle aspiration biopsy cytology (FNAB-C) and core needle biopsy tissue (CNB-T) with the addition of thyroglobulin (Tg) in the washout of the needle or BRAF V600E mutation assessment in assessing cervical lymph node metastasis (LNM) in papillary thyroid carcinoma.

Materials and Methods

A total of 186 lymph nodes were punctured by fine or core needle. The diagnostic performance of FNAB-C and CNB-T with Tg in the washout or BRAF V600E mutation assessment was compared.

Results

The optimal cutoff value of FNAB-Tg was 1.0 ng/ml, with an AUC of 0.976. The sensitivity and specificity of FNAB-C in predicting cervical LNM were 97.4% and 71.4%, respectively, and the addition of FNAB-Tg could contribute to a sensitivity of 100% and a specificity of 95%, but the introduction of BRAF V600E mutation assessment was associated with a decreased sensitivity of 96.3% and a decreased specificity of 50.0%. The FNAB-Tg level showed a comparable distribution in malignant lymph nodes with different TgAb statuses, serum TSH levels, and serum Tg levels. The sensitivity and specificity of CNB-T in predicting cervical LNM were 98.9% and 100%, respectively. The addition of CNB-Tg did not alter the diagnostic ability, but the introduction of BRAF V600E mutation assessment obtained the best performance, with a sensitivity of 100% and specificity of 100%.

Conclusion

The sensitivity and specificity of FNAB-C could be increased if combined with FNAB-Tg. CNB-T alone could provide satisfactory diagnostic reliability.

Analytical validation of eight methods of thyroglobulin measurement in fine-needle aspiration washouts

BACKGROUND

Thyroglobulin (Tg) assay in washout fluids of fine needles, after cervical lymph nodes aspiration, is used for detecting metastases from differentiated thyroid carcinomas. Assay methods are the same as for Tg in serum. However, with non-serum samples, methods require extensive validation to notably check for the absence of matrix effect. This study fits this context. Our objectives were to assess analytic performances, in washout fluid, of eight different Tg assay methods and to compare them to validated data in serum.

METHODS

Eleven medical laboratories participated in this study. The matrix tested was phosphate-buffer saline containing 1% bovine serum albumin (PBS-1% BSA). Samples used were dilutions, in this buffer, of Certified Reference Material (CRM 457). We verified, for all methods, the limit of detection, precision, linearity, trueness and accuracy.

RESULTS

In PBS-1% BSA, the functional sensitivities (FS) were comparable to those expected for serum. All the methods were linear. The relative biases of trueness were between -24.5 and 10.2% around 1 µg/L. Total analytical error was ≤40% near the functional sensitivity values.

CONCLUSION

No quantitatively important matrix effect was observed. All the methods showed their ability to measure Tg in PBS-1% BSA, over the concentration range of interest, with acceptable total analytical error. We validated the functional sensitivity value as a decision threshold in thyroidectomized patients after treatment and with low concentrations of serum Tg.

Comparison of the diagnostic performances of US-guided fine needle aspiration cytology and thyroglobulin measurement for lymph node metastases in patients with differentiated thyroid carcinoma: a meta-analysis

OBJECTIVES

Ultrasound (US)-guided fine needle aspiration cytology (FNAC) and thyroglobulin measurement (FNA-Tg) are two common methods for confirming lymph node metastases (LNM) in patients with differentiated thyroid carcinoma (DTC). This study aimed at comparing the diagnostic performance of FNAC, FNA-Tg alone, and in combination by means of a meta-analysis.

METHODS

Eligible articles were selected according to predefined criteria, and their quality was evaluated as per the QUADAS-2 checklist. We calculated pooled sensitivity (Se), specificity (Sp), positive/negative likelihood ratio, and diagnostic odds ratio (DOR), and plotted the summary receiver operating characteristic (SROC) curve using the Meta-DiSc1.4 software.

RESULTS

Twenty-one studies pooling 1662 malignant and 1279 benign LNs from 2712 patients with DTC were included. The results showed that FNAC was more specific (pooled Sp, 0.98) while FNA-Tg was more sensitive (pooled Se, 0.94). FNAC and FNAC+FNA-Tg performed better postoperatively than FNA-Tg, while FNA-Tg performed better preoperatively. The combination of FNAC and FNA-Tg could achieve a better diagnostic performance than each alone (DOR 446.00, area under the curve [AUC] 0.9862), no matter preoperatively (DOR 378.14, AUC 0.9879) or postoperatively (DOR 788.72, AUC 0.9930). Besides, the combination of FNAC and FNA-Tg/serum-Tg ratio obtained a higher Sp (0.98) than the combination of FNAC and FNA-Tg.

CONCLUSION

The addition of FNA-Tg, especially the FNA-Tg/serum-Tg ratio, to FNAC could increase the diagnostic performance of LNM in both preoperative and postoperative patients with DTC. Since one test or test combinations could perform differently according to the clinical situation, the best-fitting test should be chosen accordingly.

KEY POINTS

• FNAC is more specific than FNA-Tg while FNA-Tg is more sensitive than FNAC. • The combination of FNAC and FNA-Tg could achieve a better diagnostic performance than either alone, no matter preoperatively or postoperatively. • The combination of FNAC and FNA-Tg/serum-Tg ratio could reach a higher Sp than the combination of FNAC and FNA-Tg.

Clinical application of the ultrasound-guided fine needle aspiration for thyroglobulin measurement to diagnose lymph node metastasis from differentiated thyroid carcinoma-literature review

Papillary thyroid carcinoma (PTC) generally has a good prognosis, but disease recurs in 25% to 30% of PTC patients and significantly reduces the survival rate. Lymph node metastasis (LNM) is reported in 20% to 50% of PTC patients, mainly in the neck, and 20% originates from recurrence. LNM of papillary thyroid carcinoma are a plausible prognostic factor to determine disease recurrence. Currently, fine needle lymph node aspiration for cytology (LN-FN-cytology) is the best modality to diagnose LNM but is limited by diagnostic sensitivity and sample error. Fine needle lymph node aspiration for thyroglobulin measurement (LN-FNA-Tg) could offer a reliable and quantitative diagnostic method for LNM. The combination of LN-FNA-cytology and LN-FNA-Tg could achieve almost 100% diagnostic sensitivity and specificity for LNM. Both treatment guidelines of the American Thyroid Association and European Thyroid Association recommend LN-FNA-Tg to diagnose LNM after total thyroidectomy. Diagnostic accuracy of the LN-FNA-Tg depends on optimal equipment, scanning protocol, skill, and experience of operators. Normal saline is mainly used for aspiration needle wash-out and buffer solution. And radioimmunoassay or immunoradiometric assay are widely used for the LN-FNA-Tg measurement. So far, there is no consensus about the diagnostic threshold of LN-FNA-Tg for positive LNM, but high LN-FNA-Tg, especially higher than 10 ng/mL, strongly favors LNM.

Cervical Lymph Node Fine-Needle Aspiration and Needle-Wash Thyroglobulin Reflex Test for Papillary Thyroid Carcinoma

Fine-needle aspiration (FNA) cytology coupled with needle-wash thyroglobulin (FNA-Tg) testing is recommended for cervical lymph node (LN) biopsies in patients with a history of papillary thyroid carcinoma (PTC). However, the procedure has not been standardized with the assay for FNA-Tg testing. A standard operating procedure (SOP) has been generated at our facility for cervical LN FNAs with Tg reflex testing on patients with a history of PTC. The procedure requires FNA cytology to be reviewed first, and all cases not positive for PTC are reflexed for FNA-Tg testing with the Beckman Access thyroglobulin assay. The thyroglobulin cutoff value is ≤ 1.0 ng/mL. From 2016 to 2017, 117 patients, including 71 women and 46 men, were identified as having a history of PTC. Patients' clinical characteristics were collected from medical records. A total of 143 LN biopsies were investigated for these patients. The results show that four out of 11 (36.4%) non-diagnostic LNs and five out of five (100%) atypical/suspicious LNs tested positive for FNA-Tg. Among these nine patients with positive thyroglobulin testing, LN metastases were proven histologically for all nine patients, and two patients were treated with LN ablation. Out of 68 LNs positive for PTC, three had FNA-Tg results. FNA-Tg testing was ordered for unknown reasons on two positive LNs (> 5000 ng/mL thyroglobulin) from one patient. The third LN was tested due to non-classic morphology, and the result was less than the cutoff value. Three patients with negative LN biopsies were tested to have elevated (> 1.0 ng/mL) thyroglobulin levels. One patient (FNA-Tg ng/mL) was proven to have multiple metastatic LNs through follow-up surgery. However, no positive LN was identified for the other two patients who had FNA-Tg level of 4.1 ng/mL and 37 ng/mL respectively. This is likely due to contamination, as these two patients had intact thyroids. In our practice, the FNA-Tg test is a very useful adjunct test to LN FNA specimens with a non-positive diagnosis in patients with a history of PTC. Furthermore, FNA-Tg testing increases diagnostic sensitivity among non-diagnostic and atypical/suspicious LNs. However, FNA-Tg testing should not substitute conventional cytology due to the following reasons: (1) false-negative thyroglobulin lab results; (2) PTC with loss of thyroglobulin expression; (3) LN metastasis from other origins; and (4) false-positive thyroglobulin testing due to blood contamination in patients who are not completely athyrotic.

Impact of Serum TSH and Anti-Thyroglobulin Antibody Levels on Lymph Node Fine-Needle Aspiration Thyroglobulin Measurements in Differentiated Thyroid Cancer Patients

BACKGROUND

Thyroglobulin measurements in the washout of fine needle aspiration (FNA-Tg) are an excellent tool to detect lymph node (LN) metastases of differentiated thyroid carcinoma (DTC). Nevertheless, how to define the best cutoffs and the influence of potential confounders are still being discussed.

OBJECTIVE

To evaluate the accuracy of FNA-Tg measurement to detect DTC metastases and the influence of thyroid status and anti-thyroglobulin antibodies (TgAb).

METHODS

One hundred thirty-eight patients with DTC and suspicious cervical LN were included. Patients underwent ultrasound (US)-guided FNA for cytological examination and FNA-Tg measurements. Final diagnoses were confirmed by histological examination or clinical and US follow-up for at least 1 year.

RESULTS

Data from 119 subjects with suspicious LN were evaluated. The median value of FNA-Tg in patients with metastatic LN (n = 65) was 3,263.0 ng/mL (838.55-12,507.5), while patients without LN metastasis (n = 54) showed levels of 0.2 ng/mL (0.2-0.2). According to the ROC curve analysis, the best cutoff value to predict metastasis was 4.41 ng/mL for FNA-Tg, with a sensitivity of 98% and specificity of 96%. There were no differences in the median of FNA-Tg measurements between those on (TSH 0.16 mUI/mL) and those off levothyroxine (TSH 99.41 mUI/mL) therapy (47.94 vs. 581.15 ng/mL, respectively; p = 0.79). Interestingly, the values of FNA-Tg in patients with LN metastasis (n = 65) did not differ between patients with positive and those with negative TgAb (88.8 vs. 3,263.0 ng/mL, respectively; p = 0.57).

CONCLUSION

US-guided FNA-Tg proved to be a useful examination in the follow-up of patients with DTC, independently of TSH status and the presence of TgAb.

Measurement of thyroglobulin, calcitonin, and PTH in FNA washout fluids

Different imaging tools, circulating endocrine markers, and fine-needle aspiration (FNA) cytology are of great importance in the diagnosis and follow-up of different thyroid and parathyroid diseases. Sometimes, however, they are conflicting or inconclusive: interestingly, measuring endocrine markers (i.e. thyroglobulin, calcitonin, parathyroid hormone) in fluids from FNA proved to be a very useful complementary diagnostic tool in such cases. The determination of endocrine markers in fluids other than serum/plasma has been developed in the last years. Although studies have reported overall satisfactory results, a good standardization of procedures has not yet been reached, and further efforts should be made in order to better define pre-analytical, analytical, and post-analytical aspects. Here we reviewed critically the literature on the measurement of FNA endocrine markers, focusing on laboratory issues, such as preparation of the sample, choice of solution, and technical features of determination of these markers. Indeed, information for use of FNA-Tg, FNA-CT, and FNA-PTH in clinical practice was also provided.

Influence of presence/absence of thyroid gland on the cutoff value for thyroglobulin in lymph-node aspiration to detect metastatic papillary thyroid carcinoma

Background

Thyroglobulin measurement with fine-needle aspiration (Tg-FNA) is a sensitive method for detecting metastatic papillary thyroid carcinoma (PTC). However, the diagnostic threshold is not well established and the influence of the thyroid gland on the cutoff value is also controversial. In this study, patients were classified into two groups according to the presence or absence of thyroid tissue, to determine an appropriate cutoff value for clinical practice.

Methods

Patients with a history of thyroid nodules or surgery for PTC and with enlarged cervical lymph nodes on an FNA examination were enrolled for Tg-FNA detection.

Results

One hundred ninety-six lymph nodes (189 patients) were included: 100 from preoperative patients, 49 from patients treated with partial thyroid ablation, and 47 from patients with total thyroid ablation. In 149 lymph nodes from patient with thyroids, the cutoff value for Tg-FNA was 55.99 ng/mL (sensitivity, 95.1%; specificity, 100%), whereas in 47 lymph nodes from patients without a thyroid, it was 9.71 ng/mL (sensitivity, 96.7%; specificity, 100%). Thus, the cutoff value for Tg-FNA was higher in patients with thyroids than in patients without thyroids.

Conclusions

The cutoff value for Tg-FNA is influenced by residual thyroid tissue, and a higher cutoff value is recommended for patients with thyroids than for patients without thyroids.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3296-3) contains supplementary material, which is available to authorized users.

Clinical impact of thyroglobulin (Tg) and Tg autoantibody (TgAb) measurements in needle washouts of neck lymph node biopsies in the management of patients with papillary thyroid carcinoma

Objectives

The presence of thyroglobulin (Tg) in needle washouts of fine needle aspiration biopsy (Tg-FNAB) in neck lymph nodes (LNs) suspected of metastasis has become a cornerstone in the follow-up of patients with papillary thyroid carcinoma (PTC). However, there are limited data regarding the measurement of anti-Tg antibodies in these washouts (TgAb-FNAB), and it is not clear whether these antibodies interfere with the assessment of Tg-FNAB or whether there are other factors that would more consistently justify the finding of low Tg-FNAB in metastatic LNs.

Materials and methods

We investigated 232 FNAB samples obtained from suspicious neck LNs of 144 PTC patients. These samples were divided according to the patient's serum TgAb status: sTgAb- (n = 203 samples) and sTgAb+ (n = 29). The TgAb-FNAB levels were measured using two different assays. Tg-FNAB was also measured using two assays when low levels (< 10 ng/mL) were identified in the first assay of the metastatic LNs from the sTgAb+ samples.

Results

The TgAb-FNAB results were negative in both assays in all samples. Low levels of Tg-FNAB were identified in 11/16 of the metastatic LNs of the sTgAb+ patients and 16/63 of the sTgAb- patients (p < 0.05) using assay 1. The measurement of the Tg-FNAB levels using assay 2 indicated additional metastases in 5 LNs of the sTgAb+ patients.

Conclusions

Factors other than the presence of TgAb-FNAB may contribute to the higher number of metastatic LNs with undetectable Tg-FNAB in the sTgAb+ group. In addition, the measurement of Tg-FNAB using different assays was useful to enhance the diagnosis of metastatic LNs, particularly when cytological and Tg-FNAB results are discordant.

Lymph node fine-needle aspiration washout thyroglobulin in papillary thyroid cancer: Diagnostic value and the effect of thyroglobulin antibodies

PURPOSE

Thyroglobulin (Tg) assessment in the needle washout after fine-needle aspiration biopsy (FNAB) of a suspicious neck lymph node (LN) is known to improve the diagnostic accuracy in patients with papillary thyroid cancer (PTC). However, there is still controversy on the best diagnostic cut-off levels for FNAB-Tg and whether thyroglobulin antibody (TgAb) positivity affects FNAB-Tg. The objectives of this study were to determine (i) the diagnostic power of different cut-offs for FNAB-Tg and (ii) if serum TgAb(+) negatively affects the FNAB-Tg evaluation.

METHODS

This was a retrospective cohort study analyzing PTC patients with suspicious neck LNs, in a university hospital setting, from October 2009 to October 2013. In total, 103 patients with PTC (226 LNs) undergoing ultrasound-guided FNAB for LNs were included. Cytology and FNAB-Tg levels were compared in reference to LN histopathology and the effect of TgAb(+) on FNAB-Tg levels was evaluated.

RESULTS

The diagnostic accuracies of FNAB-Tg cut-off of 1 and 10 ng/mL were 94.1% and 88.2%, respectively. Raising the cut-off from 1 to 10 ng/mL led to decreased sensitivity rates (91.9% vs. 83.9%). The receiver operating characteristic curve analysis demonstrated that the best FNAB-Tg cut-off was 1.2 ng/mL. There were no LNs with an FNAB-Tg ≥ 10 ng/mL that turned out to be cytologically or histopathologically benign. FNAB-Tg levels of the histopathologically malignant LNs were similar between TgAb (+) and TgAb (-) patients (p = 0.546). Serum Tg predicted FNAB-Tg levels above 1 ng/mL (p = 0.002) and FNAB-Tg predicted malignant histopathology (p = 0.004), both independently of the TgAb status of the patient.

CONCLUSIONS

FNAB-Tg ≥ 1 ng/mL has a superior diagnostic power, irrespective of TgAb (+), in PTC patients with suspected LN involvement.

Ultrasonographic differentiation of cervical lymph nodes in patients with papillary thyroid carcinoma after thyroidectomy and radioiodine ablation: a prospective study

OBJECTIVE

The objective of the present study was to validate an ultrasound (US) classification of cervical lymph nodes (LNs) in patients with papillary thyroid cancer (PTC) after thyroidectomy and radioactive iodine (131I) ablation.

METHODS

We performed a prospective study in which the patients were submitted to thyroidectomy and 131I ablation and then followed until neck US revealed LN(s) ≥5 mm. A total of 288 LNs from 112 patients with PTC were evaluated. Patient management was based on LN characteristics grouped according to the classification system studied here.

RESULTS

The presence of microcalcifications and/or cystic degeneration of cervical LNs were highly suggestive of a metastatic etiology (specificity of 99.4%). In contrast, the most sensitive finding for LNs affected by PTC was the absence of an echogenic hilum (sensitivity of 100%). In the absence of these findings (microcalcifications, cystic degeneration, echogenic hilum), a metastatic etiology was the most likely in the case of a round LN (specificity of 89%). The differentiation of a spindle-shaped LN without a visible hilum by Doppler analysis permitted us to dichotomize an initial probability of metastases of 13% in 25% (with peripheral vascularization) versus 3.3% (without peripheral vascularization).

CONCLUSIONS

Our results confirm that the classification proposed for cervical LNs in patients with PTC is valid for determining patient management following initial therapy.

Estimation of thyroglobulin in lymph node aspirates: Pilot experience from a tertiary referral cancer center

Background:

Assessment of cervical lymph node involvement in patients with thyroid cancer either during preoperative surgical mapping or detection of recurrences during follow-up is a crucial step in the management of differentiated thyroid cancers (DTCs). In most patients, fine needle aspiration cytology (FNAC) confirms the presence of metastasis in lymph node. However, in cases of paucicellular lymph node aspirate or discordant sonogram and cytology results, thyroglobulin (Tg) measurement in the lymph node aspirate (FNA-Tg) is useful and a value >1 ng/ml is considered consistent with metastatic disease.

Context:

The addition of FNAC to the US improves the specificity, but 5–10% are nondiagnostic and 6–8% rate of false-negative results. Several studies have reported that the detection of Tg in FNA-needle washes improves the evaluation of suspicious lymph nodes in patients with DTC.Data from Indian centers on FNA-Tg are limited.

Aims:

We piloted the utility of FNA-Tg in patients with sonographically suspicious cervical lymph node enlargement in the setting of suspicious thyroid nodule or in the follow-up of thyroid cancer.

Settings and Design:

Prospective data collection.

Results:

We measured Tg in 13 lymph node aspirates (12 patients, 10 females) among whom 4 patients had a total thyroidectomy and 1 had a hemithyroidectomy. Eight of the 13 lymph node aspirates had FNA-Tg values >150 ng/ml, all of them had unequivocal malignant cytology and four among them had proven metastatic DTC on surgical pathology. The median FNA-Tg of the patients with malignant cytology was 7550 ng/ml with a range of 162–30,000 ng/ml. Among the remaining 5 lymph node aspirate, 2 lymph nodes showed cytological features suggestive of reactive lymphadenitis (FNA-Tg <0.2 ng/ml) and were not operated, 1 had a high-grade malignancy consistent with anaplastic thyroid cancer (FNA-Tg <0.2 ng/ml), and 2 had nondiagnostic cytology (one had non-caseating granuloma on surgical pathology [FNA-Tg 1.3 ng/ml] and in the other patient [FNA-Tg <0.2 ng/ml] surgical intervention was deferred).

Conclusions:

FNA-Tg was concordant with positive cytology in all patients with DTC and may serve as a useful tool in patients with negative and nondiagnostic cytology to guide surgical management.

Improvement in the Detection of Cystic Metastatic Papillary Thyroid Carcinoma by Measurement of Thyroglobulin in Aspirated Fluid

Cystic change in metastatic lymph nodes of papillary thyroid carcinoma (PTC) is a diagnostic challenge for fine needle aspiration (FNA) because of the scant cellularity. The aim of this study was to evaluate the measurement of thyroglobulin in fine needle aspirate (Tg-FNA) for detecting metastatic PTC in patients with cystic neck lesions and to validate the optimal cutoff value of Tg-FNA. A total of 75 FNA specimens of cystic lesions were identified, including 40 of metastatic PTC. Predetermined threshold levels of 0.04 (minimum detection level), 0.9, 10.0, and 77.0 ng/mL (maximum normal serum-Tg level) were used to evaluate the diagnostic accuracy of Tg-FNA for metastatic PTC detection. The areas under the receiver operating characteristic curve for diagnosing metastatic PTC of Tg-FNA values of 0.04, 0.9, 10.0, and 77.0 ng/mL were 0.5 (95% confidence interval [CI], 0.382–0.618), 0.645 (95% CI, 0.526–0.752), 0.945 (95% CI, 0.866–0.984), and 0.973 (95% CI, 0.907–0.996), respectively. With a cutoff value of 77.0 ng/mL, the combination of Tg-FNA and FNA cytology showed superior diagnostic power (97.5% sensitivity and 100% specificity) compared to FNA cytology alone (80% sensitivity and 100% specificity). We recommend a Tg-FNA cutoff of 77.0 ng/mL, the maximum normal serum-Tg level, for cystic neck lesions.

Influence of thyroid gland status on the thyroglobulin cutoff level in washout fluid from cervical lymph nodes of patients with recurrent/metastatic papillary thyroid cancer

BACKGROUND

The influence of serum thyroglobulin (Tg) and thyroidectomy status on Tg in fine-needle aspiration cytology (FNAC) washout fluid is unclear.

METHODS

A total of 282 lymph nodes were prospectively subjected to FNAC, fine-needle aspiration (FNA)-Tg measurement, and frozen and permanent biopsies. We evaluated the diagnostic performance of several predetermined FNA-Tg cutoff values for recurrence/metastasis in lymph nodes according to thyroidectomy status.

RESULTS

The diagnostic performance of FNA-Tg varied according to thyroidectomy status. The optimized cutoff value of FNA-Tg was 2.2 ng/mL. However, among FNAC-negative lymph nodes, the FNA-Tg cutoff value of 0.9 ng/mL showed better diagnostic performance in patients with a thyroid gland. An FNA-Tg/serum-Tg cutoff ratio of 1 showed the best diagnostic performance in patients without a thyroid gland.

CONCLUSION

Applying the optimal cutoff values of FNA-Tg according to thyroid gland status and serum Tg level facilitates the diagnostic evaluation of neck lymph node recurrences/metastases in patients with papillary thyroid carcinoma (PTC). © 2015 Wiley Periodicals, Inc. Head Neck 38: E1705-E1712, 2016.

Lowered cutoff of lymph node fine-needle aspiration thyroglobulin in thyroid cancer patients with serum anti-thyroglobulin antibody

OBJECTIVE

Fine needle aspiration cytology (FNAC) and measurement of thyroglobulin (Tg) in needle washout (FNA-Tg) are recommended for the diagnosis of metastatic or recurrent lymph nodes (LNs) in differentiated thyroid cancer (DTC). However, the effect of serum Tg antibody (TgAb) on FNA-Tg levels still remains unclear in the preoperative setting. We analyze the interference of serum TgAb on FNA-Tg levels as proof of concept in the diagnostic advantage of serum TgAb combined with FNA-Tg.

SUBJECTS AND METHODS

A total of 370 suspicious cervical LNs from 273 patients with DTC were included. The primary tumor was confirmed as DTC on preoperative pathology in all patients. We performed FNA-Tg measurement and FNAC on suspicious LNs and evaluated the diagnostic performance of FNAC and FNA-Tg according to TgAb status. Final diagnoses were confirmed by histological examination of excised specimens or by follow-up ultrasonography for at least 6 months.

RESULTS

Data from 273 subjects with suspicious 370 LNs were evaluated. Fifty-five LNs (14.9%) were from TgAb+ positive serum TgAb (TgAb+) patients. Serum Tg and FNA-Tg levels were significantly lower in patients with TgAb+ than in those with TgAb-negative (TgAb-). Final pathology confirmed 109 LNs (29.5%) as malignant. Diagnostic performance of FNA-Tg at the same cutoff level was lower in the TgAb+ than TgAb- group. FNA-Tg cutoff levels determined by ROC curve were lower in the TgAb+ group.

CONCLUSION

The results suggested that the cutoff value of FNA-Tg should be lowered in suspicious LN before thyroidectomy in thyroid cancer patients with TgAb.

Diagnostic values of thyroglobulin measurement in fine-needle aspiration of lymph nodes in patients with thyroid cancer

We aimed to evaluate the diagnostic performance of measuring the concentration of thyroglobulin (Tg) in the washout fluid of the needle aspiration (FNA-Tg). We performed a systematic search of MEDLINE (inception to October 2013) and EMBASE (inception to October 2013) for English publications using keywords "thyroid", "aspiration", "washout", and "thyroglobulin". All searches were limited to human studies. We included studies of FNA-Tg measurement in the washout fluid rinsed with 1 ml of normal saline. Eight studies including 843 lymph nodes (LNs) were eligible for this study. The pooled sensitivity and specificity of preoperative studies are 0.89 [95 % CI 0.82-0.95], 0.60 [0.49-0.70], and those of postoperative studies are 1.0 [0.83-1.0], 1.0 [0.92-1.0]. To determine best cutoffs from each preoperative and postoperative study, the distance between the point (0, 1) and each observed cutoff values (1-specificity, sensitivity) was calculated, and the distance is minimal when the cutoff value of 32.04 for preoperative studies and of 0.9 for postoperative one are selected. FNA-Tg can be used for both preoperative and postoperative evaluation of LN metastasis. Although the cutoff values for the FNA-Tg has not been standardized, preoperative values of 32.04 ng/ml and postoperative values of 0.9 ng/ml are recommended for identifying neck LN metastasis.

Thyroglobulin level in fine-needle aspirates for preoperative diagnosis of cervical lymph node metastasis in patients with papillary thyroid carcinoma: two different cutoff values according to serum thyroglobulin level

BACKGROUND

Measurement of thyroglobulin (Tg) in the washout fluid of fine-needle aspirates (FNA-Tg) is useful for diagnosis of lymph node (LN) metastasis in papillary thyroid carcinoma (PTC). However, the cutoff value of FNA-Tg in the preoperative state is not defined clearly. This study aimed to evaluate the optimal cutoff value of preoperative FNA-Tg according to serum Tg level.

METHODS

FNA-Tg was measured in 135 PTC patients (160 LNs) for preoperative diagnosis of cervical LN metastasis.

RESULTS

Of the 160 LNs, 119 (74%) were surgically removed and 110 (69%) were diagnosed as malignant. When we adopted a FNA-Tg of 1.0 μg/L as the cutoff value, the sensitivity and specificity were 99% and 76%, respectively. FNA-Tg levels were correlated with serum Tg levels (Pearson's coefficient 0.42, p=0.002) and the FNA-Tg levels of 12 of the 50 benign LNs were above 1.0 μg/L. We classified the LNs into two groups according to serum Tg level regardless of anti-Tg antibody status: a low Tg group (≤1.0 μg/L, n=22, 14%) and a high Tg group (>1.0 μg/L, n=138, 86%). In the low Tg group, the sensitivity and specificity of the FNA-Tg cutoff value of 1.0 μg/L were 93% and 100%, respectively. In the high Tg group, the sensitivity and specificity of the FNA-Tg cutoff value of 19.0 μg/L were 93% and 100%, respectively. A Tg ratio (FNA-Tg level divided by serum Tg level) of 0.5 gave an improved diagnostic performance (sensitivity, 98%; specificity, 98%) in the high Tg group.

CONCLUSIONS

FNA-Tg levels in the preoperative state are affected by serum Tg levels when they exceeded 1.0 μg/L. For the preoperative diagnosis of metastatic cervical LNs, it seems reasonable to employ different cutoff values of FNA-Tg depending on serum Tg levels. We propose the use of an optimal cutoff value of FNA-Tg of 1.0 μg/L in patients with low serum Tg levels and a Tg ratio of 0.5 in those with high serum Tg levels irrespective of thyroglobulin antibody status.

Thyroglobulin measurement by highly sensitive assays: focus on laboratory challenges

Differentiated thyroid cancer (DTC) is the most common endocrine cancer and its incidence has increased in recent decades. The initial treatment consists of total thyroidectomy followed by ablation of thyroid remnants by radioiodine in most cases. As thyroid cells are the only source of thyroglobulin (Tg), circulating Tg serves as a biochemical marker of persistent or recurrent disease in the follow-up of DTC. Due to the suboptimal clinical detection rate of older Tg assays endogenous or exogenous thyrotropin (TSH) stimulations are recommended for unmasking occult disease. However, the development of new Tg assays with improved analytical sensitivity and precision at low concentrations now allows detection of very low Tg concentrations, reflecting minimal amounts of thyroid tissue, even without the need for TSH stimulation. Even if the use of these assays still has not found its way in current clinical guidelines, such assays are now increasingly used in clinical practice. As serum Tg measurement is a technically challenging assay and criteria to define a ‘highly sensitive’ assay may be different, a good knowledge of the technical difficulties and interpretation criteria is of paramount importance for both clinical thyroidologists, laboratory physicians and scientists involved in the care of DTC patients.

Excessive iodine intake and thyroid dysfunction among lactating Saharawi women

OBJECTIVES

Excessive iodine intake may lead to thyroid dysfunction, which may be particularly harmful during pregnancy and lactation. The main objective was to describe iodine status and the prevalence of thyroid dysfunction among lactating women in areas with high iodine (HI) and very high iodine (VHI) concentrations in drinking water.

DESIGN AND METHODS

A cross-sectional survey was performed among 111 lactating women in the Saharawi refugee camps, Algeria. Breast milk iodine concentration (BMIC), urinary iodine concentration (UIC) and the iodine concentration in the most commonly consumed foods/drinks were measured. A 24-h dietary recall was used to estimate iodine intake. Thyroid hormones and antibodies were measured in serum.

RESULTS

Median UIC, BMIC and iodine intake across both areas was 350 μg/L, 479 μg/L and 407 μg/day, respectively. In multiple regression analyses, we discovered that being from VHI area was associated with higher UIC and BMIC. BMIC was also positively associated with iodine intake. Thyroid dysfunction and/or positive thyroid antibodies were found in 33.3% of the women, of which 18.9% had hypothyroidism and 8.1% had hyperthyroidism and 6.3% had positive antibodies with normal thyroid function. Elevated thyroid antibodies were in total found in 17.1%. We found no difference in distribution of thyroid dysfunction or positive antibodies between HI and VHI areas. BMI, BMIC and elevated thyroglobulin (Tg) predicted abnormal thyroid function tests.

CONCLUSIONS

The high prevalence of thyroid dysfunction may be caused by excessive iodine intake over several years.

Any detectable thyroglobulin in lymph node biopsy washouts suggests local recurrence in differentiated thyroid cancer

The sensitivity of local recurrence detection in differentiated thyroid cancer (DTC) is increased by measuring thyroglobulin in needle washouts from lymph node fine-needle aspiration biopsies (FNA-Tg). Recent studies have proposed minimum diagnostic threshold values for FNA-Tg and have reported interference from Tg antibodies (Tg Ab), leading to low or false-negative results. The aim of this study was to assess the utility of FNA-Tg in the diagnosis of local DTC recurrence in patients referred to a single pathology service used by our tertiary teaching hospital, the first such study in an Australian cohort. Data were collected from the pathology service database for FNA-Tg over an 18-month period, and the results of 69 FNA-Tg samples from 57 patients were obtained. FNA-Tg findings were compared with cytology and histology when patients proceeded to surgery. Using the functional sensitivity as the cut-off, detectable FNA-Tg (≥0.9 μg/l) had a sensitivity of 95.7%, specificity of 50% and positive predictive value of 95.7%. Our results suggest that detectable FNA-Tg leads to histological confirmation of local nodal DTC recurrence and would support a decision to proceed to surgery. Serum Tg Ab can, however, interfere with FNA-Tg measurements. Thus, we now recommend routine use of FNA-Tg washouts in all lymph node FNA biopsies for the detection of DTC recurrence.

Thyroglobulin in lymph node fine-needle aspiration washout: a systematic review and meta-analysis of diagnostic accuracy

CONTEXT

The thyroglobulin measurement in the needle washout after fine-needle aspiration (FNA) has been reported to increase the sensitivity of FNA in identifying lymph node (LN) metastases from differentiated thyroid cancer (DTC).

OBJECTIVE

The aim of the study was to estimate the diagnostic accuracy of this technique.

DATA SOURCES

To identify eligible studies, we searched electronic databases for original articles in English from 1975 through 2013.

STUDY SELECTION

Studies that enrolled participants with suspicious neck LNs during thyroid nodule workup or thyroid cancer follow-up were included.

DATA EXTRACTION

Working independently, authors used a standard form to extract data. For quality assessment, QUADAS2 guidelines were applied.

DATA SYNTHESIS

Including all the selected studies (24 studies, 2865 LNs) in the pooled analysis, overall sensitivity was 95.0% (95% confidence interval [CI], 93.7-96.0%), specificity was 94.5% (95% CI, 93.2-95.7%), and diagnostic odds ratio (DOR) was 338.91 (95% CI, 164.82-696.88) with significant heterogeneity (inconsistency [I(2)] = 65.7%; heterogeneity, P < .001). Stratifying different populations and including only patients with thyroid gland (410 LNs), pooled sensitivity was 86.2% (95% CI, 80.9-90.5%), specificity was 90.2% (85.1-94.0%), and DOR was 56.621 (22.535-142.26; I(2) = 37.3%; heterogeneity, P = .121). Including only patients after thyroidectomy (1007 LNs), pooled sensitivity was 96.9% (95% CI, 94.9-98.2%), specificity was 94.1% (91.7-96.0%), and DOR was 407.65 (198.67-836.46; I(2) = 0.0%; heterogeneity, P = .673).

CONCLUSIONS

Thyroglobulin measurement in washout from LN FNA has high accuracy in early detection of nodal metastases from DTC. The technique is simple, but a better standardization of criteria for patient selection, analytical methods, and cutoff levels is required.

Thyroglobulin in the washout fluid of lymph-node biopsy: what is its role in the follow-up of differentiated thyroid carcinoma?

BACKGROUND

The clinical evaluation of enlarged local lymph nodes (LNs) is difficult at the beginning and throughout the follow-up of differentiated thyroid carcinoma (DTC). Although the examination of samples collected from LNs by fine-needle aspiration biopsy cytology (FNAB-C) is extremely specific for the diagnosis of metastases, its sensitivity is low, especially in paucicellular samples.

SUMMARY

The measurement of thyroglobulin (Tg) in the fine-needle aspiration biopsy (FNAB) washout fluid (FNAB-Tg) increases the diagnostic performance of cytology to up to 100% sensitivity and specificity. However, the application of FNAB-Tg is currently hindered by the absence of methodological standardization, a lack of definite cutoff points, and the ongoing debate regarding its accuracy in nonthyroidectomized patients, those with elevated serum Tg, and those with circulating anti-Tg antibodies.

CONCLUSION

FNAB-Tg improves the diagnostic performance of FNAB-C in LN metastases, even when the latter is unable to diagnose the metastases. For that reason, FNAB-Tg should be included in the monitoring of DTC.

The value of thyroglobulin in washout of fine needle aspirate from 16 cervical lesions in patients with thyroid cancer

BACKGROUND AND OBJECTIVE

Thyroglobulin in the needle washout (Tg-FNA) and cytology of fine needle aspiration (cyto-FNA) are recommended for diagnosis of metastatic lymphadenopathies and recurrence of differentiated thyroid cancer. The objective of this study was to assess the value of these procedures in 16 cervical masses from patients with thyroid cancer of the follicular epithelium (TC).

PATIENTS AND METHODS

The study included six patients with TC and cervical lymphadenopathies evaluated before initial thyroid surgery and 10 patients followed up after TC surgery with cervical lumps discovered. FNA was performed in all 16 masses. Results of cyto-FNA, Tg-FNA and of the combined tests were compared to the final diagnosis of each lesion.

RESULTS

Among 10 lesions proven to be malignant at surgery, cyto-FNA, Tg-FNA and the combination of both allowed for adequate diagnosis in 7, 9, and 10 cases respectively. Among 6 lesions considered to be benign, cyto-FNA was able to confirm diagnosis in 4, was non-diagnostic in one, and was falsely negative in the remaining case, while Tg-FNA was below the established cut-off value (to consider malignancy) in all cases.

CONCLUSIONS

In patients with TC and suspect cervical masses, Tg-FNA improved the diagnostic yield of cyto-FNA alone, thus warranting its routine recommendation when FNA is performed. However, universal standardization of the technique and definition of valid cut-off thyroglobulin values (depending on the immunoassay used) above which the lesion should be considered to be malignant are still pending.

Optimized cutoff value and indication for washout thyroglobulin level according to ultrasound findings in patients with well-differentiated thyroid cancer

BACKGROUND AND PURPOSE

Washout thyroglobulin provides evidence for metastatic or recurrent lesions, However, the cutoff value is still controversial. We investigated an optimized cutoff value and indication for the use of washout thyroglobulin from fine-needle aspiration in neck lymph nodes from preoperative or postoperative patients with well-differentiated thyroid cancers.

MATERIALS AND METHODS

A total of 177 lymph nodes from 161 patients underwent sonographically guided fine-needle aspiration cytology and washout thyroglobulin measurement and then underwent surgery and clinical follow-up. We assessed an optimized cutoff value of washout thyroglobulin for diagnosing metastasis and compared its diagnostic performance with that of washout thyroglobulin > 10 ng/mL, the currently accepted cutoff value. We also analyzed diagnostic performances of fine-needle aspiration cytology alone and of the combination of fine-needle aspiration cytology and washout thyroglobulin on the basis of the presence or absence of suspicious ultrasonographic findings.

RESULTS

Of the 177 lymph nodes, 77 were metastases and 100 were benign. An optimized cutoff value for washout thyroglobulin was 1.8 ng/mL. The sensitivity and negative predictive value in diagnosing metastasis improved significantly with a cutoff value of 1.8 ng/mL compared with a cutoff value of 10 ng/mL (P = .0412 for sensitivity, P = .0188 for negative predictive value). In patients with suspicious ultrasonographic findings, applying washout thyroglobulin along with fine-needle aspiration cytology significantly enhanced the sensitivity and negative predictive value of fine-needle aspiration cytology performances to 100% and 100%, respectively (P = .0051, and P = .0088). There was no difference in diagnostic performance between fine-needle aspiration cytology and the combination of the 2 methods in patients without suspicious ultrasonographic findings.

CONCLUSIONS

Applying the optimized cutoff value of washout thyroglobulin of 1.8 ng/mL in patients with suspicious ultrasonographic features facilitates the diagnostic evaluation of neck lymph nodes in both preoperative and postoperative patients with well-differentiated thyroid cancer.

Thyroglobulin in washout fluid from lymph node fine-needle aspiration biopsy in papillary thyroid cancer: large-scale validation of the cutoff value to determine malignancy and evaluation of discrepant results

CONTEXT

There are still some controversies regarding the cutoff value and the influential factors of thyroglobulin (Tg) concentration in washout fluid from fine-needle aspiration (FNA) biopsy (FNA-Tg) on cervical lymph nodes (LNs) in patients with papillary thyroid cancer (PTC).

OBJECTIVE

Our aims were to validate the cutoff value of FNA-Tg in diagnosing malignant LNs on a large scale and to investigate the influential factors that could result in the discrepancy between the final diagnosis and FNA-Tg.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a retrospective cohort study based on hospital records with 528 cases of FNA-Tg measurement from 419 PTC patients.

MAIN OUTCOME MEASURE

The cutoff value of FNA-Tg was obtained from receiver operating characteristic analysis with final diagnosis. Binary logistic regression analysis was performed to investigate the influential factors.

RESULTS

In the final diagnosis, 190 LNs were malignant, and 338 LNs were benign. The median FNA-Tg was 521.2 (3676.8) ng/mL in malignant LNs, and 0.1 (0.2) ng/mL in benign LNs. The optimal cutoff value of FNA-Tg in distinguishing malignant LNs from benign LNs was 1.0 ng/mL (sensitivity, 93.2%; specificity, 95.9%) in all cases. Combining FNA-Tg and FNA cytology showed superior diagnostic power (sensitivity, 98.4%; specificity, 94.4%) when compared with diagnostic strategy using either FNA cytology or FNA-Tg alone. FNA-Tg, serum TSH, and serum Tg were higher in nonthyroidectomized patients than in thyroidectomized patients (P < .001, respectively). FNA-Tg was correlated with serum TSH and Tg levels (P < .001, respectively), and binary logistic regression analysis showed that serum TSH suppression and serum Tg presence independently affected the diagnosis made by FNA-Tg.

CONCLUSIONS

Our results validated 1.0 ng/mL of FNA-Tg as a cutoff value for diagnosing LN metastasis of PTC and suggested that serum TSH suppression and serum Tg presence should be considered in diagnosing LN malignancy with FNA-Tg in PTC patients.

Thyroglobulin wash testing in the surveillance of patients with thyroid carcinoma: proposal for a reflex test

OBJECTIVE

Fine needle aspiration (FNA) cytology with thyroglobulin wash (TG-W) testing is recommended for follow-up of patients with differentiated thyroid carcinoma (DTC). The goal of this retrospective study was to determine if TG-W results contributed to the management of cases with positive FNA cytology.

STUDY DESIGN

We reviewed data on patients with positive and suspicious cytology results, undergoing lymph node or thyroid bed FNA with TG-W testing as part of the preoperative or follow-up investigation of histologically proven DTC in our institution and from the literature.

RESULTS

Of 30 positive/suspicious lymph node and thyroid bed FNAs in our institution, 22 (73%) had an elevated (>1 ng/ml) TG-W level. Seven of 8 TG-W-negative cases had DTC on follow-up. Of 577 cytology-positive/suspicious FNAs in the literature, 557 (97%) showed TG-W-positive results. Fourteen of 20 TG-W-negative cases had DTC on follow-up. All patients in retrospective and literature review groups with positive and suspicious FNA cytology and available follow-up were treated for recurrent or metastatic disease regardless of TG-W results.

CONCLUSION

Observations of both our and other institutions support a recommendation of reflex FNA TG-W testing only for cases with negative or indeterminate cytology results.

Usefulness of thyroglobulin measurement in needle washouts of fine-needle aspiration biopsy for the diagnosis of cervical lymph node metastases from papillary thyroid cancer before thyroidectomy

In evaluating cervical lymph node (LN) metastasis from papillary thyroid cancer (PTC), ultrasonography (US)-guided fine-needle aspiration biopsy (FNAB) is very important tool. There were limited number of studies about the diagnostic value of thyroglubion measurement in FNAB (FNAB-Tg) in non-thyroidectomized patients. Therefore, in this study, the authors evaluated the role of FNAB-Tg in diagnosing cervical LN metastases in patients with PTC before thyroidectomy. A total 91 suspicious LNs of 68 patients were undergone US-guided FNAB-Tg and cytology. Any FNAB-Tg concentration above 50 ng/ml considered as positive, irrespective of thyroid gland presence. Based on the final pathology, 49 LNs were positive, and the remaining 42 LNs were negative for metastasis. The sensitivity, specificity, and accuracy of FNAB-Tg in thyroidectomized patients were 80.0, 100.0, and 88.9%, respectively. The diagnostic performance of FNAB-Tg was not compromised by the presence of thyroid gland (sensitivity, specificity and accuracy = 95.0, 90.9 and 93.2%, respectively). FNAB-Tg is useful and simple method for the diagnosis of metastatic cervical LNs from PTC. The diagnostic performance of FNAB-Tg was not compromised by the presence of thyroid gland. Therefore, FNAB-Tg could be performed actively for the LN staging of PTC.

Diagnostic performance of thyroglobulin value in indeterminate range in fine needle aspiration washout fluid from lymph nodes of thyroid cancer

PURPOSE

The purpose was to compare the frequency of metastatic and nonmetastatic lymph nodes diagnosed by fine needle aspiration biopsy cytology (FNAC) and thyroglobulin concentration from fine needle aspiration biopsy washout fluid (FNAB-Tg) in an indeterminate range (0.2-100 ng/mL), and to evaluate the most appropriate threshold value of FNAB-Tg in an indeterminate range.

MATERIALS AND METHODS

We performed ultrasound-guided FNAB and FNAB-Tg in suspicious metastatic cervical lymph nodes of papillary thyroid carcinoma and performed surgery. Ninety-five lymph nodes with indeterminate values of FNAB-Tg ranging from 0.2-100 ng/mL in ninety-two patients were included in this study. The diagnostic performances in multiple Tg levels (0.7, 1.0, 5.0, 10.0, 20.0, 50.0) were evaluated to compare with FNAB cytology using sensitivity, specificity, and accuracy with area under the curve (AUC) analysis.

RESULTS

Forty-two were metastatic lymph nodes and fifty three were nonmetastatic lymph nodes. FNAB-Tg ranged from 0.22 to 90.9 ng/mL in metastatic lymph nodes (mean; 34.3 ± 33.3 ng/mL) and 0.20 to 56.7 ng/mL in nonmetastatic lymph nodes (mean; 4.9 ± 11.1 ng/mL) (p<0.001). The most excellent diagnostic performance was displayed in 5 ng/mL of FNAB-Tg with AUC of 0.76, sensitivity, specificity, accuracy, 69.0, 83.0, and 76.8, respectively. However, there was no significant difference from 10 ng/mL FNAB.

CONCLUSION

We ascertained that 5 ng/mL yielded the most excellent diagnostic performance among FNAB-Tg levels in the present setting with a large series with the indeterminate range (0.2-100 ng/mL) of FNAB-Tg values. These results need additional confirmation under different laboratory conditions.

Efficacy of ultrasound-guided percutaneous ethanol injection treatment in patients with a limited number of metastatic cervical lymph nodes from papillary thyroid carcinoma

CONTEXT

Repeated neck explorations can be a difficult task in patients with recurrent metastatic cervical lymph nodes from papillary thyroid carcinoma (PTC).

OBJECTIVE

The aim of this retrospective study has been to assess the efficacy of ultrasound (US)-guided percutaneous ethanol injection (PEI) as treatment of metastatic cervical lymph nodes from PTC.

MATERIALS AND METHODS

Sixty-nine patients who previously had undergone thyroidectomy for PTC were selected for inclusion. However, three patients were later excluded due to lack of follow-up. Lymph node status was determined by US-guided fine-needle aspiration biopsy and/or by raised levels of thyroglobulin in washouts from the cytological needle. Guided by US, 0.1-1.0 ml of 99.5% ethanol was injected into the metastatic lymph nodes.

RESULTS

Three patients (eight metastatic lymph nodes in total) were reassigned to surgery due to progression (multiple new metastases), leaving 63 patients and 109 neck lymph nodes to be included. Mean observation time was 38.4 months (range, 3-72). A total of 101 of the 109 (93%) metastatic lymph nodes responded to PEI treatment, 92 (84%) completely and nine incompletely. Two did not respond, and four progressed. Two lymph nodes previously considered successfully treated showed evidence of malignancy during follow-up. No significant side effects were reported.

CONCLUSION

US-guided PEI treatment of metastatic lymph nodes seems to be an excellent alternative to surgery in patients with a limited number of neck metastases from PTC. This procedure should replace "berry picking" surgery.

Thyroglobulin measurement in fine-needle aspiration biopsy of metastatic lymph nodes after rhTSH stimulation

BACKGROUND

Thyroglobulin measurement in the washout of the needle used in fine-needle aspiration cytology (FNAC) has been proposed for the early detection of lymph node metastasis both in patients with or without serum thyroglobulin antibodies; however, up to now, there have been no reports that recombinant human thyrotropin (rhTSH) stimulation modifies thyroglobulin measurement in lymph node aspirates.

METHODS

We described, after rhTSH stimulation, the switching from undetectable to detectable levels of thyroglobulin in fine-needle aspiration fluid from a suspected metastatic lymph node in 2 patients.

RESULTS

We hypothesized that thyroglobulin levels in the lymph node increased after rhTSH stimulation. The excess thyroglobulin saturates all thyroglobulin antibody binding sites and becomes detectable, explaining why it was undetectable when TSH was suppressed.

CONCLUSION

On the basis of our experience, we suggest submitting to thyroglobulin measurement in the washout of the needle used in FNAC all patients with detectable serum thyroglobulin antibody after rhTSH stimulation.

Good practice guide for cervical ultrasound scan and echo-guided techniques in treating differentiated thyroid cancer of vesicular origin

Good practice guide for cervical ultrasound scan and echo-guided techniques in treating differentiated thyroid cancer of vesicular origin. American, European and French Recommendations for the treatment of differentiated vesicular thyroid cancer were recently published. Cervical ultrasound scanning is now considered a key examination in the follow-up of these cancers. This examination is noninvasive, easy to perform and to obtain, is not costly, but remains operator-dependent. To date, there are no recommendations published that assemble all the technical aspects, results, indications and the limits of this examination in the initial medical report and the follow-up of these cancers. In order to standardise the procedure and validate the quality of the examination, a workgroup made up of a panel of experts particularly involved in carrying out ultrasound scans was set up. The aim was to draw up a good practice guide for performing cervical ultrasound scans and echo-guided techniques in treating patients with differentiated thyroid cancer of vesicular origin. The main objectives are to: (a) standardise the procedure and reports, (b) define the criteria for establishing whether lesions identified during a cervical ultrasound scan are malignant or benign, (c) standardise the indications for carrying out cytological tests and an in situ assay of markers, (d) help doctors to select the patients who ought to receive a cervical ultrasound scan and or cytological tests, (e) discuss how frequently the examinations should be carried out depending on the risk of recurrence.

Lymph node thyroglobulin measurement in diagnosis of neck metastases of differentiated thyroid carcinoma

Aim. Enlarged cervical lymph nodes (LNs) in patients with thyroid cancer are usually assessed by fine-needle aspiration cytology (FNAC). Thyroglobulin (Tg) is frequently elevated in malignant FNAC needle wash specimens (FNAC-Tg). The objectives of the study were to (1) determine an appropriate diagnostic cut-off for FNAC-Tg levels (2) compare FNAC and FNAC-Tg results in a group of 108 patients affected by differentiated thyroid carcinoma (DTC). Methods. A total of 126 consecutive FNACs were performed on enlarged LNs and the final diagnosis was confirmed by surgical pathology examination or clinical follow-up. The best FNAC-Tg cut-off level was selected by receiver operating curve analysis, and diagnostic performances of FNAC and FNAC-Tg were compared. Results. The rate of FNAC samples adequate for cytological examination was 77% in contrast FNAC-Tg available in 100% of aspirates (P < .01). The sensitivity, specificity, and accuracy of FNAC were 71%, 80%, 74%, 100%, 80%, and 94%, respectively. The most appropriate cut-off value for the diagnosis of thyroid cancer metastatic LN was 1.1 ng/mL (sensitivity 100%, specificity 100%). Conclusions. The diagnostic performance of needle washout FNAC-Tg measurement with a cut-off of 1.1 ng/mL compared favorably with cytology in detecting DTC node metastases.

Measurement of human epidermal growth factor receptor type-2 extracellular domain and cancer antigen 15-3 levels in needle washout fluid: a potential adjunct to the cytological diagnosis of breast cancer

To determine whether the measurement of biomarkers in the needle washout fluid after fine needle aspiration cytology could strengthen cytological diagnosis, 29 benign lesions, 26 ductal carcinomas in situ (DCIS), and 95 invasive carcinomas of the breast were analyzed. Immediately after the aspiration samples were expelled onto glass slides, the needle was rinsed out with 2 ml of saline. Human epidermal growth factor receptor two extracellular domain (HER2-ECD) and cancer antigen 15-3 (CA 15-3) in the washout fluid were measured using chemiluminescence. The measuring limit for HER2-ECD (0.5 ng/ml) and that for CA 15-3 (4 U/ml) were used as the cutoff values, respectively. The proportion of patients with positive HER2-ECD values was 6.9% in cases of benign lesions, 26.9% in DCIS, and 10.5% in invasive carcinomas. The proportion of patients with positive CA 15-3 values was 6.9% in cases of benign lesions, 42.3% in DCIS, and 10.5% in invasive carcinomas. The proportion of patients with any biomarker elevation was 6.9% in cases of benign lesions, 46.2% in DCIS, and 15.8% in invasive carcinomas. Thus, biomarker elevation was most frequent in cases of DCIS, followed by invasive carcinomas (P < 0.01). HER2-ECD values over 6 ng/ml or CA 15-3 values over 25 U/ml were seen exclusively in cases of DCIS or invasive ductal carcinomas with an extensive intraductal component. If the biomarker status is included, 5 of 12 cases of DCIS with equivocal cytology categories would be upgraded. Further clinicopathological validation is necessary before applying this new approach to the clinical setting.