Yamamoto Hiroki, Oura Shoji, Shintani Hiroshi
Department of Surgery, Kishiwada Tokushukai Hospital, Kishiwada-city, Japan.
Radiol Case Rep. 2025 May 22;20(8):3951-3955. doi: 10.1016/j.radcr.2025.04.121. eCollection 2025 Aug.
A 65-year-old woman showed abnormal positron emission tomography findings in the liver after breast cancer surgery. Computed tomography showed a hepatic mass with faint ring enhancement. Magnetic resonance imaging (MRI) of the liver mass showed low signals on T1-weighted images, faint high signals on fat-suppressed T2-weighted images, nominal enhancement both on early and late phase images, and distinct low signals on hepatobiliary images. Ultrasound, however, could not depict any mass images in the liver. The patient underwent diagnostic endoscopic laparotomy, revealing a visible liver tumor through the liver surface in the segment 5. Laparoscopic ultrasound was also unable to depict any tumor images even by directly placing the ultrasound probe just on the exposed tumor. Pathological study of the resected mass showed that a well-circumscribed mass was composed of atypical cells growing in solid and trabecular fashions with little nuclear atypia, focal shelf-like arrangement of nuclei, a fine vascular network, small interstitial components between tumor cell clusters, and no peri-tumoral inflammatory cells/fibrous components, and had 3 daughter nodules. In addition, CD56, synaptophysin, and chromogranin positivities of the tumors led to the diagnosis of metastatic neuroendocrine tumors (NET). Diagnostic physicians should note that ultrasound may fail to show mass images even of well-circumscribed metastatic NETs to the liver.
一名65岁女性在乳腺癌手术后肝脏正电子发射断层扫描结果异常。计算机断层扫描显示肝脏有一肿块，呈轻微环形强化。肝脏肿块的磁共振成像（MRI）在T1加权图像上呈低信号，脂肪抑制T2加权图像上呈轻微高信号，早期和晚期图像均有轻度强化，肝胆图像上呈明显低信号。然而，超声未能显示肝脏内的任何肿块图像。患者接受了诊断性内镜剖腹手术，在肝5段的肝表面发现了一个可见的肝肿瘤。即使将超声探头直接置于暴露的肿瘤上，腹腔镜超声也未能显示任何肿瘤图像。切除肿块的病理研究显示，一个边界清楚的肿块由以实体和小梁方式生长的非典型细胞组成，核异型性小，核呈局灶性架状排列，有精细的血管网络，肿瘤细胞簇之间有小的间质成分，无肿瘤周围炎性细胞/纤维成分，并有3个卫星结节。此外，肿瘤的CD56、突触素和嗜铬粒蛋白呈阳性，从而诊断为转移性神经内分泌肿瘤（NET）。诊断医生应注意，即使是边界清楚的肝脏转移性NET，超声也可能无法显示肿块图像。
