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

• Published in: Diagnostic cytopathology 2016-03, Vol.44 (3), p.177-186
• Main Authors: Aydin, Cevdet, Ozdemir, Didem, Sacikara, Muhammed, Polat, Sefika Burcak, Yazgan, Aylin Kilic, Turkolmez, Seyda, Onal, Eda Demir, Ersoy, Reyhan, Cakir, Bekir
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biopsy, Fine-Needle - methods; Biopsy, Fine-Needle - standards; Data Interpretation, Statistical; differentiated thyroid cancer; Female; Humans; lymph node washout; Lymph Nodes - pathology; Male; Middle Aged; Sensitivity and Specificity; thyroglobulin; Thyroglobulin - blood; Thyroid Neoplasms - pathology
• ISSN: 8755-1039; 1097-0339
• DOI: 10.1002/dc.23414

Background High values of fine needle aspiration washout thyroglobulin (FNAB‐Tg) are diagnostic for metastatic lesions of thyroid cancer. However, there is not a consensus on cutoff for high FNAB‐Tg level. In this study, we aimed to determine a more accurate and standardized parameter for FNAB‐Tg. Methods Ultrasonographically suspicious lymph nodes of patients with histopathologically confirmed differentiated thyroid cancer or malignant/suspicion for malignancy cytology were included. Tg washout was obtained by aspiration and nonaspiration fine needle biopsy (nonaspiration‐FNB). Simultaneous Tg was measured from serum. Aspiration and washout procedures were also performed from whole blood and serum using syringes and needles identical to ones used for lymph node biopsy. Results Data of 19 lesions in 17 patients who underwent lymph node dissection were analyzed. Nonaspiration FNB‐Tg, FNAB‐Tg/whole blood washout‐Tg, nonaspiration FNB‐Tg/whole blood washout‐Tg, nonaspiration FNB‐Tg/serum washout‐Tg, nonaspiration FNB‐Tg/serum Tg ratios were significantly higher in malignant lymph nodes compared to benign ones. Areas under the ROC curve for nonaspiration FNB‐Tg, FNAB‐Tg/whole blood washout‐Tg, FNAB‐Tg/serum washout‐Tg, nonaspiration FNB‐Tg/whole blood washout‐Tg, nonaspiration FNB‐Tg/serum washout‐Tg, and nonaspiration FNB‐Tg/serum Tg were statistically significant for the discrimination of benign and malignant lymph nodes. Best cutoff value for nonaspiration FNB‐Tg was 4.21. Among ratios, best cutoff values were 5.40 for nonaspiration FNB‐Tg/whole blood washout‐Tg and 3.28 for nonaspiration FNB‐Tg/serum washout‐Tg. Conclusion For detection of malignant lymph nodes, determining ratios of nonaspiration FNB‐Tg to whole blood and/or serum washout‐Tg might be a promising method to increase accuracy and provide standardization of lymph node washout procedure Diagn. Cytopathol. 2016;44:177–186. © 2015 Wiley Periodicals, Inc.