Manivannan P, Siddaraju N, Gopalakrishnan S
Departments of Pathology and Otorhinolaryngology, Jwaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
Cytopathology. 2014 Jun;25(3):190-8. doi: 10.1111/cyt.12124. Epub 2013 Dec 12.
To identify the most useful cytomorphological features of follicular variant of papillary thyroid carcinoma (FVPTC).
Fine needle aspiration cytological features of seven histologically proven FVPTCs were systematically evaluated in a blinded manner for various architectural, nuclear, cytoplasmic and background features with special reference to nuclear morphology.
Most smears were moderate to highly cellular with clustered and/or repetitive microfollicles, rare macrofollicles and minimal thick gummy colloid. Six of seven cases showed significant nuclear crowding/overlapping. Fairly uniform nucleomegaly (mostly three to five times the size of a mature lymphocyte) of intact neoplastic cells and enlarged naked nuclei were prominent features in all seven cases, whereas enlarged ovoid nuclei were seen in two cases. Chromatin was fine to coarsely granular and evenly distributed. Occasional nuclear grooves (NGs) and intranuclear cytoplasmic inclusions (INCIs) were seen in five and three cases, respectively. This refined approach led to a precise diagnosis of FVPTC in six cases, which were earlier interpreted as various follicular lesions. Follicular hyperplasia was excluded by the absence of significant amounts of colloid and atretic naked nuclei, whilst the possibility of follicular adenoma or follicular carcinoma was excluded by the presence of one or more features suggestive of papillary thyroid carcinoma.
Our study showed a high cell yield, microfollicular pattern, nuclear overcrowding/overlapping, scanty gummy colloid and enlarged naked nuclei as the most consistent features of FVPTC. Although inconsistent, features such as enlarged ovoid nuclei and syncytial clusters were complementary to the diagnosis in the absence of NGs and INCIs.
确定甲状腺乳头状癌滤泡变体（FVPTC）最有用的细胞形态学特征。
对7例经组织学证实的FVPTC的细针穿刺细胞学特征进行系统的盲法评估，观察各种结构、核、细胞质和背景特征，特别关注核形态。
大多数涂片细胞量中等至高，有簇状和/或重复性微滤泡，罕见大滤泡，且厚粘性胶体极少。7例中有6例显示明显的核拥挤/重叠。完整肿瘤细胞的核显著均匀增大（大多为成熟淋巴细胞大小的三到五倍）以及裸核增大是所有7例的突出特征，而2例可见卵圆形核增大。染色质细至粗颗粒状且分布均匀。5例和3例分别可见偶尔的核沟（NGs）和核内细胞质包涵体（INCIs）。这种精细的方法在6例中做出了FVPTC的准确诊断，这些病例早期被解释为各种滤泡性病变。由于不存在大量胶体和闭锁裸核，排除了滤泡增生，而由于存在一个或多个提示甲状腺乳头状癌的特征，排除了滤泡性腺瘤或滤泡癌的可能性。
我们的研究表明，高细胞产量、微滤泡模式、核拥挤/重叠、少量粘性胶体和裸核增大是FVPTC最一致的特征。虽然不恒定，但在不存在核沟和核内细胞质包涵体的情况下，卵圆形核增大和合体细胞簇等特征对诊断有补充作用。
