Special AT-rich sequence-binding protein 2 (SATB2) is a sensitive and specific biomarker for sporadic colonic adenocarcinomas. Previous studies have found that SATB2 is lost in some adenocarcinomas and dysplasias associated with inflammatory bowel disease (IBD). In establishing these findings, the prior studies did not examine cases of IBD interpreted as indefinite for dysplasia. We examined SATB2 expression in this diagnostic category to determine if any potential loss is associated with a diagnosis of definitive dysplasia on follow-up. To investigate this possibility, we collected 87 biopsies of IBD indefinite for dysplasia from 62 patients and stained them with SATB2. Among patients’ indefinite for dysplasia, we found SATB2 loss in 6/62 (9.7%). Among those with follow-up (n=51), we observed 5/6 (83%) with a future dysplasia in those with SATB2 loss compared with 10/45 (22%) in those with SATB2 retention, absolute difference 61.1% (95% confidence interval=28.9%-93.3%). We conclude that loss of SATB2 on biopsies otherwise interpreted as IBD indefinite for dysplasia may mark a population at high risk for showing definitive dysplasia on future biopsies.

富含 AT 的特殊序列结合蛋白 2 (SATB2) 是散发性结肠腺癌的敏感且特异的生物标志物。先前的研究发现 SATB2 在一些腺癌和与炎症性肠病 (IBD) 相关的发育异常中缺失。在建立这些发现时，先前的研究并未检查被解释为不确定的不典型增生的 IBD 病例。我们检查了这一诊断类别中的 SATB2 表达，以确定是否有任何潜在的损失与随访中明确的发育不良的诊断相关。为了研究这种可能性，我们收集了 62 名患者的 87 份不定型 IBD 活检组织，并用 SATB2 对它们进行染色。在不确定的不典型增生患者中，我们发现 6/62 (9.7%) 的患者存在 SATB2 缺失。在进行随访的患者中 (n=51)，我们观察到 SATB2 缺失的患者中 5/6 (83%) 未来发育不良，而 SATB2 保留的患者中这一比例为 10/45 (22%)，绝对差异 61.1%（ 95% 置信区间=28.9%-93.3%）。我们的结论是，活检中 SATB2 缺失，否则被解释为不典型增生的 IBD，可能标志着未来活检中显示明确不典型增生的高风险人群。