Classic Papillary Thyroid Carcinoma with Tall Cell Features and Tall Cell Variant Have Similar Clinicopathologic Features

Abstract

BackgroundThe tall cell variant of papillary thyroid carcinoma (TCVPTC) is more aggressive than classic papillary thyroid carcinoma (PTC), but the percentage of tall cells needed to diagnose TCVPTC remains controversial. In addition, little is known about the clinicopathologic features of classic PTC with tall cell features (TCF).MethodsWe retrospectively selected and reviewed the clinicopathologic features and presence of the BRAF mutation in 203 cases of classic PTC, 149 cases of classic PTC with TCF, and 95 cases of TCVPTCs, which were defined as PTCs having <10%, 10-50%, and ≥50% tall cells, respectively.ResultsTCVPTCs and classic PTCs with TCF did not vary significantly in clinicopathologic characteristics such as pathologic (p) T stage, extrathyroidal extension, pN stage, lateral lymph node metastasis, or BRAF mutations; however, these features differed significantly in TCVPTCs and classic PTCs with TCF in comparison to classic PTCs. Similar results were obtained in a subanalysis of patients with microcarcinomas (≤1.0 cm in size).ConclusionsClassic PTCs with TCF showed a similar BRAF mutation rate and clinicopathologic features to TCVPTCs, but more aggressive characteristics than classic PTCs.

Tall cell variant of papillary thyroid carcinoma: current evidence on clinicopathologic features and molecular biology

“…Current evidence suggests that the BRAF mutation has a higher prevalence in TCV with reports ranging from 80% to 100% when compared to cPTC with same reports ranging from 63% to 83% [5, 26, 28, 39, 48]. Thus, the higher prevalence of BRAF mutation may play a role in the aggressive biological behavior of the TCV.…”

“…Following this, the demographic and clinical data of those cases was extracted from each literature source using a pretested form and analyzed using the statistical software SPSS version 16.0 (IBM, New York, USA) and Stata 11.0. A total of 24 individual studies [3–8, 13, 15–28, 39, 59, 66] including 874 patients with TCV met the criteria for critical analysis of the clinical data. To avoid duplicate record, three studies [31, 34, 43] based on SEER database were excluded from data analysis, but they were included in related discussion.…”

“…Therefore, they recommended the threshold of tall cells in the tumor for the diagnosis of TCV should be set at 30%. However, two other studies [27, 28] found that PTC with ≥10% tall cells demonstrated more aggressive clinicopathologic features than cPTC, and they suggested the presence of more than 10% tall cells in a tumor should be reported on final pathology reports. Considering the controversial definition on TCV at present, it is rational that the presence of foci of tall cells should be mentioned in pathologic reports irrespective of percentage of tall cell cytology found as suggested by LiVolsi VA [29].…”

“…It is difficult to perform a well-conducted survival analysis study in a relatively rare disease with a low death rate. Most studies [5, 26, 28, 39] demonstrated TCV as a more aggressive variant of PTC with higher recurrence and poorer survival compared with cPTC. Similarly, a meta-analysis performed with 131 cases concluded that TCV was a negative prognostic indicator in PTC [40].…”

Incidental diagnosis of the tall-cell variant of the papillary microcarcinoma of the thyroid gland requires completion lymphadenectomy: case report

“…Papillary thyroid carcinoma (PTC) is the most common type (80 %) of the thyroid neoplasms [1]. Usually, it is associated with an excellent prognosis and 5-year overall survival of up to 95% [1][2][3][4].…”