Thyroid Aspiration Cytology: Current Status

Abstract

In the adult population, thyroid nodules are common and are increasingly detected by ultrasound examination or other scanning techniques. Depending on their size and ultrasonographic features, these nodules may require further investigation, including tissue diagnosis. Fine-needle aspiration (FNA) has become the predominant method to obtain tissue for microscopic analysis. In October 2007, the National Cancer Institute sponsored a conference to review the state of the science for the use of FNA in the management of thyroid nodules. This conference reviewed indications for thyroid FNA and pre-FNA requirements, training and credentialing, techniques for thyroid FNA, diagnostic terminology and morphologic criteria, utilization of ancillary studies, and post-FNA testing and treatment options. The results of those discussions have been published in both print and electronic versions. The aim of the current article was to discuss indications for FNA, diagnostic terminology, and post-FNA options, issues that are important to physicians who are managing patients with thyroid nodules. CA Cancer J Clin 2009;59: 99-110.

Contributory Factors to Hemorrhage After Ultrasound-Guided Fine Needle Aspiration of Thyroid Nodules with an Emphasis on Patients Taking Antithrombotic or Anticoagulant Medications

“…Thus, starting FNA using a thinner needle is recommended and thicker needles should generally be reserved for draining viscous colloid cysts. Generally, two to five passes seem reasonable to ensure an adequate sample (2,(35)(36)(37). Our results show that the incidence of hemorrhagic complications increased with an increase in the number of passes.…”

“…Our results show that the incidence of hemorrhagic complications increased with an increase in the number of passes. In previous studies, there were no statistically significant differences between the capillary sampling technique and FNA with suction with regard to diagnostic accuracy (37)(38)(39)(40). In our study, the hemorrhage complication rate was not significantly different between the two techniques.…”

“…Hence, the choice between the capillary sampling technique and FNA with suction may depend on operator preference (5,9,41). If a nodule is largely cystic or predominantly cystic, sampling should be done in the residual solid component after aspiration of the fluid component (5,11,37). Hemorrhage may occur soon after fluid aspiration, probably as a result of the sudden reduction in intra-nodular pressure (42).…”

A High-Resolution Melting Protocol for Rapid and Accurate Differential Diagnosis of Thyroid Nodules

“…7 The major limitations of FNAB procedures are linked to inadequate and indeterminate specimens and, in that sense, are also linked respectively to the nondiagnostic or follicular lesions categories. 8,9 Thus, a clinical need emerges for the characterization of aspirates with suspicious features but with unsatisfactory cellularity, to allow accurate distinction of benign from malignant forms of follicular lesions.Several somatic mutations have been identified in thyroid cancer, stimulating the search for genetic alterations in FNAB that could increase the diagnostic accuracy of traditional cytology. Numerous studies have demonstrated that identification of specific mutations in cytological specimens can assist in the diagnosis by FNAB and in the clinical decision to excise the nodule and to intensify the follow-up.…”

“…7 The major limitations of FNAB procedures are linked to inadequate and indeterminate specimens and, in that sense, are also linked respectively to the nondiagnostic or follicular lesions categories. 8,9 Thus, a clinical need emerges for the characterization of aspirates with suspicious features but with unsatisfactory cellularity, to allow accurate distinction of benign from malignant forms of follicular lesions.…”