Department of Diagnostic Radiology, Kyoto Second Red Cross Hospital, 355-5 Haruobi-cho, Kamigyo-ku, Kyoto, 602-8026, Japan.
Department of Radiology, Japan Community Health care Organization Kyoto Kuramaguchi Medical Center, 27 Shimofusa-cho, Kita-ku, Kyoto, 603-8151, Japan.
Abdom Radiol (NY). 2020 Jul;45(7):2279-2285. doi: 10.1007/s00261-020-02442-5.
We report on four patients with the nested variant of urothelial carcinoma (NVUC) of the urinary bladder and focus on their magnetic resonance imaging (MRI) findings. MRI showed that all lesions had irregular wall thickening with little protrusion into the bladder lumen. All had extravesical invasion, and two had invaded other organs (uterus and seminal vesicle). On T2-weighted images, all tumors mainly showed relatively strong hypointensity similar to that of the muscularis propria, and in three cases there was also a thin hyperintense layer on the tumor surface, suggesting edematous mucosa. Diffusion-weighted images demonstrated different degrees of hyperintensity, which was faint in one case. Dynamic contrast-enhanced MRI was performed in two cases and both showed gradual contrast enhancement. It has been suggested that NVUC may produce unique MRI findings reflecting its pathological features. It would be useful for those who interpret bladder MRI to recognize this rare urothelial carcinoma variant.
我们报告了 4 例膀胱巢状尿路上皮癌（NVUC）患者，并重点介绍了他们的磁共振成像（MRI）表现。MRI 显示所有病变均有不规则的壁增厚，很少向膀胱腔内突出。所有患者均有膀胱外侵犯，2 例患者侵犯了其他器官（子宫和精囊）。在 T2 加权图像上，所有肿瘤主要表现为与固有肌层相似的相对强的低信号，3 例肿瘤表面还有一层薄的高信号，提示水肿的黏膜。弥散加权图像显示不同程度的高信号，1 例信号较弱。2 例行动态对比增强 MRI 检查，均表现为逐渐增强。有人认为，NVUC 可能产生反映其病理特征的独特 MRI 表现。对于解读膀胱 MRI 的人来说，认识这种罕见的尿路上皮癌变异是有用的。
