Department of Oncology, University of Turin and Pathology Unit, San Luigi Hospital, Regione Gonzole 10, 10043, Orbassano, Torino, Italy.
Internal Medicine Unit, San Luigi Hospital, Orbassano, Turin, Italy.
J Endocrinol Invest. 2021 Apr;44(4):803-809. doi: 10.1007/s40618-020-01377-4. Epub 2020 Aug 14.
The clinical impact of the SIAPEC/SIE 2014 classification for thyroid cytology has been addressed in few studies that evaluated the malignancy rate and the relative prevalence of each category. No study analyzed its intra-observer and inter-observer reproducibility, so far.
We retrospectively collected all "indeterminate" lesions diagnosed before (2011-2014) and after (2015-2018) the application of the SIAPEC/SIE 2014 classification at our Institution. Their relative malignancy risks were calculated based on available histological diagnoses. Cytological and clinical features of TIR3A were compared with the surgical outcome. Finally, a large set of samples was re-evaluated in blind of the original cytological and histological diagnoses by two pathologists, independently.
The prevalence of "indeterminate" diagnoses increased in years 2015-2018 (302/1482, 21% with 14% of TIR3A and 7% TIR3B categories) compared to years 2011-2014 (261/1680, 16%). Surgery was performed in 27% TIR3A and in 97% TIR3B cases. Malignancy rates were 40% for TIR3B and 17% for TIR3A, but were greatly influenced by the adoption of the WHO 2017 re-classification of encapsulated follicular-patterned lesions (decreasing to 28% and 6%, respectively). No criteria except for tumor size were associated to malignancy in TIR3A category. Intra-observer agreement of the experienced pathologist was 122/141 (86%), whereas inter-observer agreement between the expert and in-training pathologist was 95/141 (67%).
In this real-life experience, the sub-classification of TIR3A and TIR3B slightly increased the overall prevalence of "indeterminate" diagnoses. Malignancy rates were higher than estimated for both TIR3A and TIR3B categories. Agreement among observers highly depended on pathologist's training.
SIAPEC/SIE 2014 甲状腺细胞学分类的临床影响在少数评估每种分类恶性肿瘤发生率和相对患病率的研究中已经得到了研究。到目前为止，还没有研究分析其观察者内和观察者间的可重复性。
我们回顾性地收集了在我们机构应用 SIAPEC/SIE 2014 分类之前（2011-2014 年）和之后（2015-2018 年）诊断的所有“不确定”病变。根据可获得的组织学诊断计算其相对恶性风险。比较 TIR3A 的细胞学和临床特征与手术结果。最后，由两名病理学家独立对大量样本进行盲法重新评估，不考虑原始细胞学和组织学诊断。
与 2011-2014 年（1680 例中的 261 例，16%，包括 14%的 TIR3A 和 7%的 TIR3B 类别）相比，2015-2018 年“不确定”诊断的比例增加（1482 例中的 302 例，21%）。TIR3A 中有 27%和 TIR3B 中有 97%的病例进行了手术。TIR3B 的恶性肿瘤发生率为 40%，TIR3A 为 17%，但由于采用了 2017 年世界卫生组织对包膜滤泡模式病变的重新分类，恶性肿瘤发生率大大降低（分别为 28%和 6%）。TIR3A 类别中除肿瘤大小外，没有其他标准与恶性肿瘤相关。经验丰富的病理学家的观察者内一致性为 141 例中的 122 例（86%），而专家和实习病理学家之间的观察者间一致性为 141 例中的 95 例（67%）。
在这种实际经验中，TIR3A 和 TIR3B 的细分略微增加了“不确定”诊断的总体患病率。TIR3A 和 TIR3B 类别的恶性肿瘤发生率均高于估计值。观察者之间的一致性高度依赖于病理学家的培训。
