Department of Pathology, Beijing Chao-Yang Hospital, Capital Medical University, No.8 Gongren Tiyuchang South Road, Chaoyang District, Beijing, 100020, China.
Department of Pathology, Aerospace Center Hospital, Beijing, China.
J Cancer Res Clin Oncol. 2022 Jul;148(7):1761-1769. doi: 10.1007/s00432-021-03757-6. Epub 2021 Aug 9.
To identify clinicopathological features for the differential diagnosis of appendiceal serrated lesions and polyps (SPs) and low-grade appendiceal mucinous neoplasm (LAMN) for the purpose of avoiding over-diagnosis.
Clinical data and pathological features of 66 patients with SPs diagnosed at the Aerospace Center Hospital between January 2013 and January 2021 were collected and compared to 22 cases of LAMN.
SPs, compared with LAMN, are likely to be associated with acute inflammation (SPs 53.0% vs. LAMN 18.2%), and may be located in the appendix partly, although with smaller diameter (average 9.6 vs. 27.2 mm); epithelial structures of serrated (100% vs. 22.7%) and filiform villous (47.0% vs. 18.2%) were often found in SPs. SPs occasionally show attenuated or flattened morphology (16.7% vs. 100%) and undulating or scalloped (7.6% vs. 40.9%) structures, and can also be accompanied by diverticulum (18.2% vs. 18.2%) and acellular mucin in the appendiceal wall (16.7% vs. 54.5%), which causes confusion with LAMN. The key point of the differential diagnosis is to observe whether the muscularis mucosa exists (loss, 0% vs. 100%) and fibrosis of the appendiceal wall (0% vs. 100%). SMA immunohistochemistry can assist in the diagnosis. Calcification is also indicative of LAMN.
The epithelial structure of SPs can appear flattened and focally scalloped, and can be accompanied by mucin in the appendiceal wall, which may appear as complex lesions, easily over-diagnosed as LAMN. Key differential diagnostic features are identifying the structure of lamina propria, determining whether the muscularis mucosa exists, and whether the appendiceal wall is fibrotic.
为了避免过度诊断，确定鉴别诊断阑尾锯齿状病变和息肉（SPs）与低级别阑尾黏液性肿瘤（LAMN）的临床病理特征。
收集并比较了 2013 年 1 月至 2021 年 1 月航天中心医院诊断的 66 例 SPs 患者的临床资料和病理特征，并与 22 例 LAMN 患者进行了比较。
与 LAMN 相比，SPs 可能与急性炎症相关（SPs 为 53.0%，而 LAMN 为 18.2%），并且可能位于阑尾的一部分，尽管直径较小（平均直径为 9.6 毫米 vs. 27.2 毫米）；锯齿状（100% vs. 22.7%）和丝状绒毛状（47.0% vs. 18.2%）上皮结构经常出现在 SPs 中。SPs 偶尔表现为萎缩或扁平形态（16.7% vs. 100%）和波浪状或锯齿状结构（7.6% vs. 40.9%），并且还可以伴有憩室（18.2% vs. 18.2%）和阑尾壁无细胞黏液（16.7% vs. 54.5%），这会导致与 LAMN 混淆。鉴别诊断的关键是观察黏膜固有层是否存在（缺失，0% vs. 100%）和阑尾壁纤维化（0% vs. 100%）。SMA 免疫组化有助于诊断。钙化也提示为 LAMN。
SPs 的上皮结构可能表现为扁平，局灶性呈锯齿状，并可伴有阑尾壁黏液，可能表现为复杂病变，容易被误诊为 LAMN。关键的鉴别诊断特征是识别固有层结构，确定黏膜固有层是否存在以及阑尾壁是否纤维化。
