Hyalinizing Trabecular Tumors of the Thyroid Gland are Almost all Benign
ABSTRACT In 1987, Carney et al reported 11 thyroid tumors with the following features: circumscription or encapsulation, trabecular architecture with intratrabecular hyalin and colloid, polygonal and spindle cells, nuclei with frequent grooves and cytoplasmic inclusions, occasional psammoma bodies, and a low mitotic rate. The neoplasms did not recur or metastasize during a follow-up period that averaged 10 years, and they were titled hyalinizing trabecular adenomas. Subsequently, the nuclear features of the neoplasm led to the introduction of 2 modified titles for it, hyalinizing trabecular tumor and hyalinizing trabecular neoplasm. Later, discovery of RET/PTC mutations in the tumor resulted in it being designated as a type of papillary thyroid carcinoma. We studied 119 neoplasms of the type outlined, collected over a 20-year period, for invasion, recurrence and metastasis, and obtained follow-up in 96% of the cases. One hundred eighteen tumors showed no evidence of aggressive behavior (capsular, vascular, and parenchymal invasion), local recurrence, or metastasis. One tumor showed vascular and capsular invasion, and pulmonary metastasis. We conclude that the overwhelming majority of hyalinizing trabecular tumors of the thyroid behave as benign neoplasms and that, at this time, hyalinizing trabecular adenoma is the most appropriate title for them.
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ABSTRACT: Background Fine-needle aspiration cytology (FNAC) is very accurate in detecting papillary thyroid carcinomas (PTCs). According to the Bethesda system for reporting thyroid cytopathology, the risk for malignancy is 97–99% when FNAC is used to diagnose PTC; the malignancy risk is 60–75% when FNAC results in suspected PTCs. The presence of hyalinizing trabecular tumor (HTT) of the thyroid can cause misdiagnosis because its cytological features mimic PTCs. However, the use of frozen section analysis can assist in the recognition of unique architecture features of HTT, and thus may help prevent the undertaking of an unnecessarily aggressive operation. Methods We retrospectively reviewed all patients diagnosed with HTT by permanent histopathology from February 2009 to October 2013. After acquired agreement of the patients, we analyzed all data and reviewed another nine cases of HTT reported in the English-language medical literature to examine the efficacy of frozen section. Results There were six patients included in our research (5 women and 1 man), with an average age of 48.8 years. Using frozen section, four patients were diagnosed with HTT and two patients were misinterpreted as PTC. Consequently, four patients had lobectomy and two patients had total thyroidectomy, with no surgical complications. Of the nine cases of HTT reviewed from the English literature, the use of frozen section showed three HTT cases, three PTC cases, two medullary thyroid carcinoma cases, and one deferral case. Overall, the use of frozen section as a diagnostic method prevented additional surgical resection in eight patients (53%). Conclusion Frozen section can sometimes but not always be used to diagnose HTT. When HTT is diagnosed by its trabecular pattern through the use of frozen section, it may prevent total thyroidectomy.Journal of the Chinese Medical Association 09/2014; 77(11). DOI:10.1016/j.jcma.2014.08.006 · 0.89 Impact Factor
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ABSTRACT: Background/Aims: Hyalinizing trabecular tumors are rare neoplasms of the thyroid gland often mistaken for thyroid carcinoma on fine-needle aspiration. We review the distinguishing characteristics of hyalinizing trabecular tumors and their management. Methods: We present the case of a patient diagnosed with papillary thyroid carcinoma on fine-needle aspiration as well as a review of the literature. Results: Intraoperative findings were felt to be inconsistent with papillary thyroid carcinoma and only a thyroid lobectomy was performed pending the results from pathologic evaluation, which confirmed a benign process and a diagnosis of hyalinizing trabecular tumor. Due to the diagnostic difficulty in distinguishing hyalinizing trabecular tumors from thyroid carcinomas on fine-needle aspiration, many patients receive overtreatment for what is primarily a benign disease. Conclusions: Recognition of hyalinizing trabecular tumors as a possible benign etiology of a thyroid mass can facilitate appropriate management. © 2013 S. Karger AG, Basel.ORL 10/2013; 75(6):309-313. DOI:10.1159/000355291 · 0.67 Impact Factor
Value in Health 11/2005; 8(6). DOI:10.1016/S1098-3015(10)67519-5 · 2.89 Impact Factor