Thyroid FNA and benign thyroid disease

Reducing Unnecessary Biopsy of American College of Radiology Thyroid Imaging Reporting and Data System Category 4 Nodules

OBJECTIVES

To assess the effectiveness of strain elastography (SE), Virtual Touch tissue imaging and quantification (VTIQ; Siemens Medical Solutions, Mountain View, CA) and their combination (SE + VTIQ) in distinguishing benign from malignant American College of Radiology Thyroid Imaging Reporting and Data System category 4 nodules (TR4) to reduce unnecessary biopsy.

METHODS

In this retrospective study, 985 thyroid nodules from 920 patients were initially enrolled and examined with conventional ultrasound, SE, and VTIQ. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of SE, VTIQ, and SE + VTIQ were calculated respectively. An area under the receiver operating characteristic curve analysis was applied to evaluate the diagnostic efficiency of SE, VTIQ, and SE + VTIQ in the differentiation of benign and malignant TR4 nodules.

RESULTS

A total of 864 patients with 922 TR4 nodules were enrolled ultimately, as 63 thyroid nodules from 56 patients were excluded because they did not meet the inclusion criteria of this study. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of SE, VTIQ, and SE + VTIQ were 72.4% versus 86.3% versus 82.1%, 77.7% versus 80.5% versus 83.5%, 70.6% versus 76.1% versus 80.2%, 73.4% versus 76.3% versus 83.5%, and 75.5% versus 79.7% versus 82.8%, respectively. The areas under the receiver operating characteristic curve for the diagnosis of TR4 nodules by SE, VTIQ, and SE + VTIQ were 0.751, 0.817, and 0.844.

CONCLUSIONS

In spite of a slight decrease in the sensitivity, the application of combining SE and VTIQ techniques can improve the specificity and accuracy of TR4 nodule diagnosis, which can help reduce unnecessary biopsies of TR4 nodules.

Diagnostic terminology and morphologic criteria for cytologic diagnosis of thyroid lesions: a synopsis of the National Cancer Institute Thyroid Fine-Needle Aspiration State of the Science Conference

The National Cancer Institute (NCI) sponsored the NCI Thyroid Fine-needle Aspiration (FNA) State of the Science Conference on October 22-23, 2007 in Bethesda, MD. The two-day meeting was accompanied by a permanent informational website and several on-line discussion periods between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document summarizes matters regarding diagnostic terminology/classification scheme for thyroid FNA interpretation and cytomorphologic criteria for the diagnosis of various benign and malignant thyroid lesions. (http://thyroidfna.cancer.gov/pages/info/agenda/).

The Delphian lymph node in thyroid cancer

OBJECTIVE

To determine the significance of Delphian lymph node (DLN) involvement in thyroid cancer.

SUMMARY BACKGROUND DATA

The DLN has long been regarded as a predictor of thyroid malignancy and indicator of advanced disease; however, there are no published data in relation to the thyroid.

METHODS

A retrospective cohort study with data obtained from the University of Sydney Endocrine Surgery database and histopathology records. The study cohort comprised 1000 consecutive patients undergoing total thyroidectomy.

RESULTS

The DLN was separately removed and identified as such in 263 of 1000 (26.3%) patients. Of 1000 patients 203 (20.3%) had a diagnosis of papillary/medullary cancer. Of this group 150 patients had surgery performed for suspected cancer, and in 53 the diagnosis of cancer was unsuspected. In only 1 case did the DLN operative appearance alert the surgeon to an otherwise unsuspected thyroid cancer. The DLN was separately identified in 103 patients with cancer and, in this group, 22 of 103 (21.4%) had DLN metastases. DLN involvement was associated with greater nodal disease (9.8 vs. 1.6 nodes; P < 0.001), larger tumor size (19.4 vs. 11.1 mm; P < 0.003) and younger age (41 vs. 47 years; P = 0.058). DLN involvement was highly predictive of further disease in the central compartment (sensitivity = 41%, specificity = 95%), moderately predictive of further disease in the lateral compartment (sensitivity = 50%, specificity = 88%), and strongly suggestive of further nodal disease in the neck (sensitivity = 64%, specificity = 100%).

CONCLUSIONS

Although the clinical appearance of the DLN is not an accurate indicator of the presence of unsuspected thyroid cancer, metastatic involvement of the DLN is an adverse prognostic marker in papillary/medullary thyroid cancer. The presence of DLN metastasis in patients with thyroid cancer should alert the surgeon to the high probability of advanced disease and need for greater attention to the central and lateral lymph node compartments.