Horne Matthew J, Chhieng David C, Theoharis Constantine, Schofield Kevin, Kowalski Diane, Prasad Manju L, Hammers Lynwood, Udelsman Robert, Adeniran Adebowale J
Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA.
Diagn Cytopathol. 2012 May;40(5):410-5. doi: 10.1002/dc.21790. Epub 2011 Aug 26.
The Bethesda 2007 Thyroid Cytology Classification defines follicular lesion of undetermined significance as a heterogeneous category of cases that are not convincingly benign nor sufficiently atypical for a diagnosis of follicular neoplasm or suspicious for malignancy. In our institution, we refer to these cases as indeterminate, and they are further sub-classified into two: (1) low cellularity with predominant microfollicular architecture and absence of colloid (IN(a)) and (2) nuclear features not characteristic of benign lesions (nuclear atypia) (IN(b)). We reviewed these indeterminate cases to document the follow-up trend using this two-tier classification. A search of the cytology records was performed for the period between January 2008 and June 2009. All thyroid fine-needle aspiration (FNA) cases were reviewed and the ones diagnosed as indeterminate were identified. Correlating follow-up FNA and/or surgical pathology reports were reviewed. The percentage of cases showing a malignancy was calculated. One hundred and seventy-one indeterminate cases were identified, representing 2.8% of the 6,205 thyroid FNA cases examined during the time under review (107 IN(a), 64 IN(b)). Records of follow-up procedures were available in 106 (61%) cases. Malignancy was identified in 27% of all indeterminate cases. This was disproportionately more in the IN(b) (56%) compared to the IN(a) (7%) cases. A diagnosis of "IN(a)" does not carry the same implication as that of "IN(b)". The IN(b) category needs a more aggressive follow-up than the IN(a) category and may justify an immediate referral for lobectomy. Despite the vague morphologic criteria for this diagnostic category, the indeterminate rate remains relatively low and falls within the NCI recommendation (<7%).
2007年贝塞斯达甲状腺细胞病理学分类将意义未明的滤泡性病变定义为一类异质性病例，这些病例既不能令人信服地诊断为良性，也没有足够的不典型性来诊断为滤泡性肿瘤或可疑恶性肿瘤。在我们机构，我们将这些病例称为不确定病例，并进一步将其分为两类：（1）细胞数量少，以微小滤泡结构为主且无胶质（IN(a)）；（2）具有非良性病变特征的核（核异型性）（IN(b)）。我们回顾了这些不确定病例，以记录使用这种两级分类法的随访趋势。对2008年1月至2009年6月期间的细胞病理学记录进行了检索。对所有甲状腺细针穿刺（FNA）病例进行了回顾，并确定了诊断为不确定的病例。查阅了相关的随访FNA和/或手术病理报告。计算了显示为恶性肿瘤的病例百分比。共确定了171例不确定病例，占在所审查期间检查的6205例甲状腺FNA病例的2.8%（107例IN(a)，64例IN(b)）。106例（61%）病例有随访程序记录。在所有不确定病例中，27%被诊断为恶性肿瘤。与IN(a)（7%）病例相比，IN(b)（56%）病例中的恶性肿瘤比例过高。“IN(a)”的诊断与“IN(b)”的诊断含义不同。与IN(a)类别相比，IN(b)类别需要更积极的随访，可能有理由立即转诊进行肺叶切除术。尽管该诊断类别的形态学标准模糊，但不确定率仍然相对较低，符合美国国立癌症研究所的建议（<7%）。
