Jaconi M, Manzoni M, Pincelli A I, Giardini V, Scardilli M, Smith A, Fellegara G, Pagni F
Department of Medicine and Surgery, Section of Pathology, University Milan Bicocca, Monza, Italy.
Department of Endocrinology, San Gerardo Hospital, Monza, Italy.
Cytopathology. 2017 Dec;28(6):495-502. doi: 10.1111/cyt.12459. Epub 2017 Sep 3.
Due to the recent proposal of the non-invasive follicular thyroid neoplasm with papillary-like nuclear feature (NIFTP) category, the authors analyse the state of the art in the challenging diagnosis of follicular thyroid neoplasms in routine practice.
A consecutive series of 200 histological diagnoses, with complete cytological correlation, was analysed following the introduction of the NIFTP definition. The study was conducted in a general hospital with a high prevalence of thyroid benign nodules that accounted for approximately 60% of surgically-treated nodules. The significant incidence of the new NIFTP category was 7%. Concurrently, a gradual decrease of the follicular variant of papillary thyroid carcinoma (fvPTC) was observed (3.5%). When evaluating the FNA biopsies within the NIFTP group, despite the systematic evaluation of nuclear crowding, enlargement, irregularities and clearing, the final cytological class was often indeterminate for malignancy (Thy3/III-IV, 71%). At histology, the application of the semiquantitative NIFTP score for the evaluation of the PTC-like nuclear features was able to discriminate benign lesions (score 0/1) from fvPTC (score 2/3). A certain degree of overlapping still persisted between NIFTP and fvPTC (score 2) or between NIFTP and benign lesions (score 1).
In the routine evaluation of FNA biopsies, the presence of subtle and questionable PTC-like nuclear features still remains a controversial aspect of the diagnostic workflow. Given that the NIFTP category was introduced to stratify the low-risk group of thyroid tumours more precisely, pathologists should force themselves to apply the nuclear score rigorously and to classify cases assigned a score of 1 as benign proliferations.
由于最近提出了具有乳头状核特征的非侵袭性滤泡性甲状腺肿瘤（NIFTP）类别，作者分析了在常规实践中滤泡性甲状腺肿瘤具有挑战性的诊断的当前状况。
在引入NIFTP定义后，对一系列连续的200例组织学诊断病例及其完整的细胞学相关性进行了分析。该研究在一家甲状腺良性结节患病率较高的综合医院进行，这些良性结节约占手术治疗结节的60%。新的NIFTP类别的显著发生率为7%。同时，观察到甲状腺乳头状癌滤泡变体（fvPTC）逐渐减少（3.5%）。在评估NIFTP组内的细针穿刺活检（FNA）时，尽管对核拥挤、增大、不规则和核空晕进行了系统评估，但最终的细胞学分类往往对恶性肿瘤不确定（Thy3/III-IV，71%）。在组织学上，应用半定量NIFTP评分评估PTC样核特征能够区分良性病变（评分0/1）和fvPTC（评分2/3）。NIFTP与fvPTC（评分2）之间或NIFTP与良性病变（评分1）之间仍存在一定程度的重叠。
在FNA活检的常规评估中，存在细微且可疑的PTC样核特征仍然是诊断流程中一个有争议的方面。鉴于引入NIFTP类别是为了更精确地对低风险甲状腺肿瘤组进行分层，病理学家应努力严格应用核评分，并将评分为1的病例分类为良性增生。
