A new approach for standardization and increased accuracy of lymph node washout thyroglobulin in patients with differentiated thyroid carcinoma

Application of Carbon Nanoparticle Tracers in the Lateral Neck Lymph Nodes of CN1bx Patients with Papillary Thyroid Carcinoma

This study aimed to investigate the applicability of carbon nanoparticle tracers in the lateral neck lymph nodes of CN1bx patients with papillary thyroid carcinoma surgery. 73 patients with papillary thyroid carcinoma at our hospital between January 2019 to December 2019 were suspected metastasis in the lateral neck lymph node before surgical treatment. During the operation, carbon nanoparticle tracers were used as black staining tracers for the lateral neck lymph nodes to detect metastasis in each Compartment of the neck. The lateral Compartment is defined as level ll-V The black-stained lymph nodes, dyed by Carbon nanoparticle tracers, and non-dyed lymph nodes were compared. Post-surgery paraffin pathology was adopted as the gold standard to calculate the predictive performance of the carbon nanoparticle tracers in detecting lymph node biopsy metastasis. 59 of the patients (80.8%) had lateral neck metastasis. The black-stained lymph nodes, dyed by Carbon nanoparticle tracers, in Compartment IV exhibited the highest proportions in the case number submitted for detection and in lymph nodes metastasis, followed by Compartment III. The metastasis rate of the dyed lymph nodes in areas III and IV was significantly higher than that of non-dyed lymph nodes (P < 0.05). The sensitivity and accuracy of the dyed lymph node biopsy in Compartments III-IV were 90% and 93.2%, respectively. This predictive performance was similar to that Compartments ll-V combined. In conclusion, when carbon nanoparticle tracers are used for lymph node biopsy, high sensitivity and accuracy are obtained in lateral neck compartments III-IV, making these compartments ideal for lymph node biopsy.

The value of serum thyroglobulin alteration after ultrasonography-guided fine-needle biopsy of suspicious cervical lymph nodes in the diagnosis of metastasis in patients with differentiated thyroid cancer

BACKGROUND

It is known that serum thyroglobulin (TG) can increase after fine-needle biopsy of thyroid nodules. We aimed to determine whether TG is increased after ultrasonography (US)-guided fine needle capillary biopsy (FNC) of suspicious cervical lymph nodes (LNs) in thyroidectomised patients and investigate the possible association between change in TG and cytology results.

MATERIAL AND METHODS

Data of 188 patients who underwent FNC of suspicious cervical LNs were retrospectively evaluated. Demographical, laboratory and ultrasonography features of LNs were noted. TG levels before FNC (TG_b-FNC ), after FNC (TG_a-FNC ), TG_a-FNC /TG_b-FNC ratio and the number of patients with increased TG were determined. Patients were grouped as benign, nondiagnostic, suspicious for malignancy and malignant according to the cytological results.

RESULTS

TG_a-FNC , TG_b-FNC /TG_a-FNC and rate of patients with increased TG were significantly higher in malignant cytology group than other groups (P < .001). The optimal cut-off level of TG increase that was predictive for malignancy was 7.6% with a sensitivity of 73.7% and specificity of 85.2%. TG increase was not associated with age, sex, Thyroid-stimulating hormone (TSH) level, anti-TG positivity and US features of LNs while significantly lower in patients who received radioactive iodine (RAI) treatment. Among 31 patients with positive anti-TG, TG_b-FNC /TG_a-FNC , and rate of patients with increased TG were higher in malignant compared to benign and nondiagnostic cytology groups.

CONCLUSIONS

Serum TG increment and rate of patients with increased TG after FNC of suspicious cervical LNs were higher in patients with malignant cytology than with all other cytology results both in all study group and in sub-group of anti-TG positive patients. Increase in TG after FNC might be an additional tool for determining LN metastasis.