Al-Toubah Taymeyah, Strosberg Jonathan
Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA.
J Neuroendocrinol. 2025 Apr;37(4):e13491. doi: 10.1111/jne.13491. Epub 2025 Jan 24.
Colonic neuroendocrine tumors (NETs), excluding rectal NETs, are often described as relatively common and aggressive, with inferior median survival compared with other gastrointestinal (GI) primary sites. However, epidemiological databases may conflate well-differentiated NETs with poorly differentiated neuroendocrine carcinomas (NECs), leading to a lack of precise data on the prevalence, clinical behavior, and prognosis of well-differentiated colonic NETs. We analyzed a large institutional database to identify patients with well-differentiated NETs originating in the colon, excluding rectal NETs. Cecal NETs were included; however, ileocecal NETs (overlapping the ileocecal valve) were not. We assessed their prevalence compared with other primary sites, grade, stage, and prognosis. Among 3639 patients with gastroenteropancreatic (GEP) NETs, only 19 (0.5%) had well-differentiated colonic NETs. This included 11 cecal and eight sigmoid colon primaries (two described as "rectosigmoid"). No tumors originated in the ascending, transverse, or descending colon. Sigmoid NETs were typically early-stage polyps discovered incidentally during colonoscopy. In contrast, eight of the 11 cecal NETs metastasized (p = .04). Six of the cecal primary patients (55%) exhibited carcinoid syndrome versus none of the sigmoid primary cases (p = .01). Well-differentiated colon NETs are exceptionally rare, comprising approximately 0.5% of GEP-NETs. These tumors fall into two distinct categories: cecal NETs, which resemble ileal NETs in behavior, and sigmoid NETs, which appear similar to rectal NETs. The broad categorization of colonic "NETs" in epidemiologic databases likely includes NECs, obscuring the true clinical picture.
结肠神经内分泌肿瘤（NETs），不包括直肠NETs，通常被描述为相对常见且具有侵袭性，与其他胃肠道（GI）原发部位相比，其生存期中位数较低。然而，流行病学数据库可能将高分化NETs与低分化神经内分泌癌（NECs）混为一谈，导致缺乏关于高分化结肠NETs的患病率、临床行为和预后的确切数据。我们分析了一个大型机构数据库，以确定起源于结肠（不包括直肠NETs）的高分化NETs患者。盲肠NETs被纳入；然而，回盲部NETs（与回盲瓣重叠）未被纳入。我们评估了它们与其他原发部位相比的患病率、分级、分期和预后。在3639例胃肠胰（GEP）NETs患者中，只有19例（0.5%）患有高分化结肠NETs。其中包括11例盲肠原发和8例乙状结肠原发（2例描述为“直肠乙状结肠”）。没有肿瘤起源于升结肠、横结肠或降结肠。乙状结肠NETs通常是在结肠镜检查时偶然发现的早期息肉。相比之下，11例盲肠NETs中有8例发生转移（p = 0.04）。6例盲肠原发患者（55%）出现类癌综合征，而乙状结肠原发病例无一出现（p = 0.01）。高分化结肠NETs极为罕见，约占GEP-NETs的0.5%。这些肿瘤分为两个不同的类别：行为类似于回肠NETs的盲肠NETs和外观类似于直肠NETs的乙状结肠NETs。流行病学数据库中对结肠“NETs”的广泛分类可能包括NECs，从而掩盖了真实的临床情况。
