Diagnostic problems in thyroid FNAs

Abstract

The use of FNA cytology to diagnose pathologic conditions of the thyroid has increased considerably in recent years, particularly since it has reduced by half the number of patients undergoing surgery. On the one hand, this diagnostic technique has attracted a certain amount of well justified criticism, but on the other, recent cytohistologic correlations and new scientific knowledge are continually improving its application. We shall discuss the latter aspect in more detail and deal with some simple but informative points which the pathologist may find useful in daily practice. Diagn. Cytopathol. 1997;17:422–428. © 1997 Wiley‐Liss, Inc.

Role of fine needle aspiration cytology in the diagnosis of papillary carcinoma thyroid: A retrospective study from north-east India

“…[5] These limitations include false negative and false positive results and a proportion of FNAC results that are not obviously benign or malignant and fall into the indeterminate or suspicious group. [10] The reported pitfalls are those related to specimen adequacy, sampling techniques, the skill of the physician performing the aspiration, the experience of the pathologist interpreting the aspirate, and the overlapping cytological features between some benign and malignant thyroid lesions. [11] A guided FNAC was certainly better in nonpalpable lesions, however, in palpable lesion even an unguided FNAC could yield equally comparable result.…”

The Accuracy of Fine Needle Aspiration on Superficial Palpable Body Masses in Patients at Tikrit City

“…The more routine use of ultrasound-guided FNA biopsy to direct sampling toward the solid nodule will minimize but not prevent the occasional false negative results. These results are not uncommon in this situation because clinically papillary carcinoma are present in at least 10% of huge multinodular goiter, this is because of multiplicity of nodules and impartiality to aspirate all of the nodules [28][29][30]. It has been demonstrated that ultrasound guidance is useful, that is it allows to direct sampling toward the solid impalpable nodules that may represent carcinoma [31].…”

Aspiration Cytopathology of Metastatic Mucinous Papillary Thyroid Carcinoma

“…Discrete intravacuolar targetoid globules are not illustrated in their example, although electron microscopy demonstrated occasional vacuoles lined by microvilli. As part of a discussion of diagnostic dilemmas in thyroid cytology, Galera-Davidson illustrates an example of PTC with mucinous intracytoplasmic vacuoles but without the targetoid-type inspissated concretions (6). Some authors in their discussion of breast carcinoma aspirates have referred to this targetoid structure as a "magenta body" because of its deep violaceous coloration and its distinctive appearance in air-dried Diff-Quik-stained smears (23).…”

“…Although reports to the contrary have been published (2)(3)(4), our impression is that many pathologists remain under the misconception that carcinomas of the thyroid are nearly all mucin-negative. This assumption from histopathology has been transferred to fine needle aspiration (FNA) cytopathology of thyroid carcinoma, where only rare descriptions or illustrations of extracellular mucin or mucin-filled vacuoles exist (5,6). The aim of this article is to illustrate and describe the FNA cytopathology (and corresponding histopathology) of a mucinous papillary thyroid carcinoma (PTC) and to discuss the potential pitfalls related to this phenomenon.…”