Hayashi Daichi, Yamamoto Masashi, Nakamatsu Dai, Matsumoto Kengo, Fukui Koji, Adachi Shiro, Nishida Tsutomu
Department of Gastroenterology, Toyonaka Municipal Hospital, Toyonaka, Osaka, 565-0871, Japan.
Department of Pathology, Toyonaka Municipal Hospital, Toyonaka, Osaka, Japan.
Clin J Gastroenterol. 2025 Feb;18(1):224-229. doi: 10.1007/s12328-024-02057-z. Epub 2024 Nov 10.
An 82-year-old man presented with intermittent abdominal pain and elevated liver enzymes. Blood tests showed normal levels of tumor markers (CEA, CA19-9, NSE). Contrast-enhanced computed tomography (CE-CT) revealed a 20 mm hypovascular mass in the pancreatic head. Magnetic resonance imaging indicated low intensity on both T1- and T2-weighted images and high intensity on diffusion-weighted images. Endoscopic ultrasonography visualized an irregular hypoechoic mass. Initially, it was diagnosed as pancreatic ductal adenocarcinoma (PDAC) based on imaging. Subsequent histopathological analysis via endoscopic ultrasound-guided fine-needle aspiration revealed a neuroendocrine tumor (NET). The preoperative diagnosis was changed to a pancreatic NET grade1. Consequently, a pancreaticoduodenectomy was performed. Histopathological examination of the resected specimen unveiled a mixed tumor-NET-Grade1/Grade3 and invasive PDAC. No clear transition between the NETs and PDAC was observed. The high grade of NET with significant fibrosis contributed to decreased enhancement of CE-CT. Finally, we diagnosed this case as a pancreatic collision tumor involving both NET and PDAC components, with lymph node metastases attributed to the NET components. In this case, achieving an accurate preoperative diagnosis was challenging despite utilizing both imaging and biopsy diagnostics. This unique case underscores the difficulties encountered in the preoperative assessment of mixed tumors.
一名82岁男性因间歇性腹痛和肝酶升高就诊。血液检查显示肿瘤标志物（癌胚抗原、糖类抗原19-9、神经元特异性烯醇化酶）水平正常。增强计算机断层扫描（CE-CT）显示胰头有一个20毫米的低血供肿块。磁共振成像显示在T1加权和T2加权图像上均为低信号，在扩散加权图像上为高信号。内镜超声显示一个不规则的低回声肿块。最初，根据影像学诊断为胰腺导管腺癌（PDAC）。随后通过内镜超声引导下细针穿刺进行的组织病理学分析显示为神经内分泌肿瘤（NET）。术前诊断改为胰腺NET 1级。因此，实施了胰十二指肠切除术。对切除标本的组织病理学检查发现是一种混合性肿瘤——NET 1级/3级和浸润性PDAC。未观察到NET与PDAC之间有明确的过渡。伴有显著纤维化的高级别NET导致CE-CT增强减弱。最后，我们将该病例诊断为包含NET和PDAC成分的胰腺碰撞瘤，淋巴结转移归因于NET成分。在这种情况下，尽管同时采用了影像学和活检诊断，但术前准确诊断仍具有挑战性。这个独特的病例凸显了混合性肿瘤术前评估中遇到的困难。
