Inflammatory and Lymphoid Lesions of the Thyroid Gland: Cytopathology by Fine-Needle Aspiration

Abstract

The cytopathologic characteristics of the inflammatory and lymphoid thyroid lesions as seen in fine-needle aspirate smears of 103 patients are reviewed, with emphasis on pitfalls and association with other neoplasms. The cytologic diagnoses were as follows: subacute thyroiditis, 3; Hashimoto's thyroiditis (HT) with or without Hürthle cell nodule, 77; HT and Hürthle cell tumor, 2; HT and follicular neoplasm, 3; HT and papillary carcinoma, 5; lymphoma, 3; HT and nodular colloid goiter, 10. Fourteen patients were operated. Five erroneous diagnoses were uncovered; inexperience was the main reason for the mistakes. The greatest diagnostic difficulties are encountered in cases of Hürthle cell nodules and malignant lymphoma, but mistakes are likely to disappear after reasonable experience. Thyroid antibodies are of no help in sorting diagnostic problems, because a positive titer is only corroborative evidence of underlying HT and does not rule out an associated tumor. Conversely, a negative titer does not discard the diagnosis of HT. The association of nodular colloid goiter and HT is depicted. Problems of sampling and staining technic are discussed.

Fine Needle Aspiration Cytology of Subacute Granulomatous Thyroiditis: A Clinico-Cytological Review of 10 Cases with Immunocytochemical Analysis

“…The cytologic literature on SGT is relatively rare, but the cytologic features of SGT has been well described. 1,[4][5][6]10,21 One report summarized the key cytologic features of SGT with performing Giemsa staining. 10 and after that, another report has been published that used Papanicolou stain.…”

“…The results of this study demonstrate that the cytological diagnosis of SGT can be improved by employing a combination of the typical and constant diagnostic cytological features and immunocytochemical results. 1,[4][5][6] In the early phase of SGT, the typical cytologic findings may be lacking and atypical follicular cells may suggest malignancy. 7 Malignant thyroid lesions can recently be easily diagnosed by immunohistochemical staining in conjunction with using the known molecular markers.…”

Nodule or Pseudonodule? Differentiation in Hashimoto's Thyroiditis with Sonoelastography

“…19 Besides the presence of true thyroid nodules (adenomatous, hyperplastic or colloidal nodules), basal inflammatory changes such as fibrotic bands and pseudonodule development may also be seen. 5 No criteria have been established, however, to diagnose and differentiate the two distinct groups of nodules by US. 20 -23 Thus, in cases where there are suspicions of the presence of real nodules, either conservative monitoring or biopsy/surgery might be needed for diagnosis, but both choices have financial and time implications.…”

Ultrasonographic appearance of focal Hashimoto’s thyroiditis: A single institution experience

“…In one retrospective study, the prevalence of cytology-proven Hashimoto thyroiditis appeared to be >10% in patients with thyroid nodules [5]. In addition to the presence of primary thyroid nodules, secondary inflammatory changes such as pseudonodule development may also be observed [6], thereby potentially complicating diagnosis. During an US diagnostic procedure, a unique form of HT, known as focal Hashimoto's thyroiditis (FHT), may present as a lesion mimicking nodular disease in US [7][8][9][10], despite the fact that these previous studies have reported that most nodular Hashimoto thyroiditis commonly appears as solid hyperechoic nodules with ill-defined margins.…”