Hoda Raza S, Arpin Ronald N, Rosenbaum Matthew W, Pitman Martha B
Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic, Cleveland, Ohio.
Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts.
Cancer Cytopathol. 2022 Mar;130(3):195-201. doi: 10.1002/cncy.22514. Epub 2021 Oct 8.
The World Health Organization (WHO) has proposed an updated international classification system for reporting pancreaticobiliary cytology. Substantial changes to the prior Papanicolaou Society of Cytopathology (PSC) system have been recommended. Chiefly, the "neoplastic: benign" and "neoplastic: other" categories have been replaced by 2 new categories-"pancreatic neoplasia-low-grade" (PaN-Low) and "pancreatic neoplasia-high-grade" (PaN-High)-stratifying neoplastic mucinous cysts by cytological atypia. Low-grade malignancies are placed in the "malignant" category and benign serous cystadenoma in the "benign/negative" category. Risk of malignancy (ROM) associated with the diagnostic categories of the WHO system has yet to be defined.
All patients who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for a pancreatic lesion at a single institution from January 2016 to December 2016, prospectively classified using the PSC system, were reclassified using the WHO system. Absolute ROM was determined by histologic outcome and/or clinical follow-up of at least 6 months.
A total of 334 EUS-FNA samples from 322 patients were reviewed and reclassified. Absolute ROM for the WHO system was 7.7% for "insufficient/inadequate/nondiagnostic" category, 1.0% for "benign/negative for malignancy," 28.0% for "atypical," 4.8% for "PaN-Low," 60.0% for "PaN-High," 100% for "suspicious for malignancy," and 100% for "malignant;" the absolute ROM for the same cohort using the PSC system was 7.7% for "nondiagnostic" category, 1.0% for "negative (for malignancy)," 28.0% for "atypical," 0.0% for "neoplastic: benign," 30.3% for "neoplastic: other," 100% for "suspicious (for malignancy)," and 100% for "positive or malignant."
The WHO international system achieves improved stratification by associated ROM compared to the PSC system.
世界卫生组织（WHO）已提议更新用于报告胰胆管细胞学的国际分类系统。有人建议对先前的细胞病理学巴氏学会（PSC）系统进行重大修改。主要是，“肿瘤性：良性”和“肿瘤性：其他”类别已被两个新类别取代——“胰腺肿瘤-低级别”（PaN-Low）和“胰腺肿瘤-高级别”（PaN-High）——根据细胞学异型性对肿瘤性黏液囊肿进行分层。低级别恶性肿瘤归入“恶性”类别，良性浆液性囊腺瘤归入“良性/阴性”类别。WHO系统诊断类别相关的恶性风险（ROM）尚未明确。
对2016年1月至2016年12月在单一机构因胰腺病变接受内镜超声引导下细针穿刺抽吸（EUS-FNA）的所有患者进行回顾，这些患者最初使用PSC系统进行前瞻性分类，现使用WHO系统重新分类。绝对ROM通过组织学结果和/或至少6个月的临床随访确定。
共回顾并重新分类了来自322例患者的334份EUS-FNA样本。WHO系统中，“不足/不充分/非诊断性”类别的绝对ROM为7.7%，“良性/恶性阴性”为1.0%，“非典型”为28.0%，“PaN-Low”为4.8%，“PaN-High”为60.0%，“可疑恶性”为100%，“恶性”为100%；同一队列使用PSC系统时，“非诊断性”类别的绝对ROM为7.7%，“（恶性）阴性”为1.0%，“非典型”为28.0%，“肿瘤性：良性”为0.0%，“肿瘤性：其他”为30.3%，“可疑（恶性）”为100%，“阳性或恶性”为100%。
与PSC系统相比，WHO国际系统通过相关ROM实现了更好的分层。
