Serrated epithelial change (SEC) in inflammatory bowel disease is most often defined as hyperplastic polyp-like mucosal change detected on random biopsies. Although SEC has been reported to be associated with an increased risk of synchronous and/or metachronous colorectal neoplasia, it remains unknown if SEC represents a form of dysplastic lesion despite the lack of morphologic evidence of dysplasia. Since the risk of colorectal neoplasia in ulcerative colitis (UC) is positively correlated with increased histologic inflammation, this study investigated if increased colonic inflammation is an independent risk factor for SEC. A cohort of 28 UC patients with SEC was analyzed and compared with 51 control UC patients without SEC. None of these patients had a history of colorectal neoplasia. For each patient with SEC, all biopsies conducted before and at the time of SEC diagnosis (versus all biopsies for each control patient) were scored by using a 4-point scoring system: no activity (no epithelial infiltration by neutrophils=0); mild activity (cryptitis only=1); moderate activity (cryptitis plus crypt abscess formation in <50% of crypts=2); and severe activity (crypt abscess formation in ≥50% of crypts, erosion, neutrophilic exudate, and/or ulceration=3). Each biopsy was designated a score, and both mean and maximum inflammation scores were calculated from all biopsies taken during each colonoscopy. The inflammation burden score was calculated for each surveillance interval by multiplying the average maximum score between each pair of surveillance episodes by the length of the surveillance interval in years. The average scores of all colonoscopies for each patient were used to assign the patient's overall mean, maximum, and inflammation burden scores. The SEC cohort included 12 (43%) men and 16 (57%) women with a mean age of 47 years at the time of the first SEC diagnosis and a long history of UC (mean: 13 y). The majority of patients (n=21; 75%) had pancolitis, and only 1 (4%) patient had primary sclerosing cholangitis. A total of 37 SEC were identified in the 28 patients, 4 (14%) of whom had multifocal SEC. SEC was predominantly found in the left colon (n=32; 86%). In the multivariate analysis, none of the 3 summative inflammation scores, including overall mean (odds ratio [OR] 1.9, P=0.489), maximum (OR 0.4, P=0.259), and inflammation burden scores (OR 1.2, P=0.223), were significantly associated with the development of SEC. Similarly, no other potential risk factors, including age, gender, ethnicity, and duration and extent of UC, were significantly correlated with the detection of SEC (P>0.05). In conclusion, the development of SEC in UC is not significantly associated with increased histologic inflammation. Given the reported association of SEC with an increased risk of synchronous and/or metachronous colorectal neoplasia, along with the presence of molecular alterations in some cases (such as TP53 mutations and aneuploidy), SEC may represent an early morphologic indicator of segmental or pan-colonic molecular abnormalities that have not advanced enough to result in colorectal neoplasia, as opposed to being a form of dysplasia.

中文翻译：

---

溃疡性结肠炎锯齿状上皮变化的发展与组织学炎症的增加没有显着相关性。

炎症性肠病中的锯齿状上皮变化（SEC）最常被定义为随机活检中检测到的增生性息肉样粘膜变化。尽管据报道 SEC 与同步和/或异时性结直肠肿瘤风险增加相关，但尽管缺乏不典型增生的形态学证据，但 SEC 是否代表不典型增生病变的一种形式仍不清楚。由于溃疡性结肠炎 (UC) 中结直肠肿瘤的风险与组织学炎症增加呈正相关，因此本研究调查了结肠炎症增加是否是 SEC 的独立危险因素。对 28 名患有 SEC 的 UC 患者进行了分析，并与 51 名没有 SEC 的对照 UC 患者进行了比较。这些患者均无结直肠肿瘤病史。对于每位患有 SEC 的患者，使用 4 分评分系统对 SEC 诊断之前和诊断时进行的所有活检（相对于每个对照患者的所有活检）进行评分：无活动（中性粒细胞无上皮浸润=0）；轻度活动（仅隐窝炎=1）；中度活动（隐窝炎加上隐窝脓肿形成<50%的隐窝=2）；严重活动（≥50% 的隐窝形成隐窝脓肿、糜烂、中性粒细胞渗出物和/或溃疡=3）。每次活检都指定一个分数，并且根据每次结肠镜检查期间进行的所有活检计算平均和最大炎症分数。通过将每对监测事件之间的平均最大分数乘以监测间隔的长度（以年为单位）来计算每个监测间隔的炎症负担分数。每个患者的所有结肠镜检查的平均评分用于分配患者的总体平均评分、最大评分和炎症负荷评分。 SEC 队列包括 12 名男性 (43%) 和 16 名女性 (57%)，首次 SEC 诊断时平均年龄为 47 岁，并且有长期 UC 病史（平均 13 岁）。大多数患者（n=21；75%）患有全结肠炎，只有 1 名（4%）患者患有原发性硬化性胆管炎。 28 名患者中总共发现了 37 个 SEC，其中 4 名（14%）患有多灶性 SEC。 SEC 主要发现于左结肠（n=32；86%）。在多变量分析中，3个炎症总结评分均未出现，包括总体平均值（比值比[OR] 1.9，P=0.489）、最大值（OR 0.4，P=0.259）和炎症负担评分（OR 1.2，P=0.223） ），与 SEC 的发展显着相关。同样，其他潜在危险因素，包括年龄、性别、种族、UC持续时间和程度，与SEC的检测没有显着相关（P>0.05）。总之，UC 中 SEC 的发生与组织学炎症的增加没有显着相关性。鉴于据报道 SEC 与同步和/或异时性结直肠肿瘤风险增加相关，以及某些病例中存在分子改变（例如 TP53 突变和非整倍体），SEC 可能代表节段性或全结肠分子异常的早期形态学指标，这些异常尚未发展到足以导致结直肠肿瘤，而不是一种不典型增生。