Faculty of Medicine, McGill University, Montreal, QC H3G 2M1, Canada.
Department of Otolaryngology-Head and Neck Surgery, McGill University, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
Curr Oncol. 2024 Oct 1;31(10):5919-5928. doi: 10.3390/curroncol31100441.
Oncocytic thyroid carcinoma (OTC) was previously considered a variant of follicular thyroid carcinoma (FTC) but has recently been reclassified as a separate form of thyroid cancer. This study aimed to demonstrate that FTC and OTC are fundamentally distinct entities that can potentially be differentiated preoperatively through cytology and/or molecular testing.
A retrospective chart review of patients diagnosed with FTC and OTC operated upon at two university health centers from January 2016 to September 2023 (n = 3219) was conducted. Molecular testing results were correlated with histopathologic diagnosis.
Fifty patients met the inclusion criteria. FTC was identified in 27 (54.0%) patients, and OTC in 23 (46.0%) patients. Patients with OTC were older (61.8 years) than FTC patients (51.2 years) ( = 0.013). Moreover, aggressive tumors were found in 39.1% (9/23) of OTCs compared to 11.1% (3/27) of FTCs ( = 0.021). Amongst Bethesda category III and IV nodules, 17 out of 20 (85.0%) OTC cytology reports demonstrated an oncocytic subtype compared to only 5 out of 24 FTC cytology reports (20.8%) ( = 0.002). On molecular testing, the alteration was exclusively present in OTCs while the and alterations were exclusively found in FTCs. Copy number alterations () were found to be more prevalent in OTC (66.7%) compared to FTC (33.3%), and they were not indicative of tumor aggressiveness. Within the OTC group, all three patients who had a alteration were diagnosed with aggressive cancer. Lastly, the OTCs exhibited a higher frequency of multiple alterations on molecular testing (66.7%) compared to FTCs (33.3%).
To our knowledge, this is the largest study to date comparing the clinical application of abnormalities found on molecular testing for FTC and OTC. It further demonstrates the distinct clinicopathological and molecular characteristics of OTC.
嗜酸细胞甲状腺癌（OTC）曾被认为是滤泡状甲状腺癌（FTC）的一种变体，但最近已被重新归类为一种独立的甲状腺癌形式。本研究旨在证明 FTC 和 OTC 是本质上不同的实体，通过细胞学和/或分子检测，术前可能将它们区分开来。
对 2016 年 1 月至 2023 年 9 月在两家大学健康中心接受 FTC 和 OTC 手术的患者进行回顾性图表审查（n = 3219）。将分子检测结果与组织病理学诊断相关联。
符合纳入标准的患者有 50 例。FTC 患者 27 例（54.0%），OTC 患者 23 例（46.0%）。OTC 患者年龄较大（61.8 岁），FTC 患者年龄较小（51.2 岁）（= 0.013）。此外，在 39.1%（9/23）的 OTC 中发现侵袭性肿瘤，而在 11.1%（3/27）的 FTC 中发现侵袭性肿瘤（= 0.021）。在 Bethesda 分类 III 和 IV 结节中，20 例 OTC 细胞学报告中有 17 例（85.0%）显示出嗜酸细胞亚型，而 24 例 FTC 细胞学报告中仅有 5 例（20.8%）（= 0.002）。在分子检测中， 改变仅存在于 OTC 中，而 和 改变仅存在于 FTC 中。拷贝数改变（）在 OTC 中更为常见（66.7%），而在 FTC 中则不常见（33.3%），并且它们与肿瘤侵袭性无关。在 OTC 组中，所有 3 例具有 改变的患者均被诊断为侵袭性癌症。最后，在分子检测中，OTC 的异常改变的频率高于 FTC（66.7% vs. 33.3%）。
据我们所知，这是迄今为止比较 FTC 和 OTC 分子检测异常的临床应用的最大研究。它进一步证明了 OTC 的独特临床病理和分子特征。
