Kim Jong Chul, Kim Kie Hwan, Jung Seungeun
Department of Diagnostic Radiology, Chungnam National University School of Medicine, Daejeon, Korea.
Korean J Radiol. 2003 Apr-Jun;4(2):130-5. doi: 10.3348/kjr.2003.4.2.130.
Primary small cell carcinoma (SCC) is a rare aggressive malignancy of the urinary bladder, with identical histopathology to that of the lung. The treatment and prognosis of bladder SCC are somewhat different from those of more frequent transitional cell carcinoma. The purpose of this study was to analyze the CT and MR imaging findings of bladder SCC.
Six adult patients (five males and one female) with pathologically proven SCC of the urinary bladder who had undergone pelvic CT and/or MR imaging were included in this study. The radiologic findings were retrospectively evaluated in terms of tumor location, texture, calcification, depth of invasion, perivesical extension, lymph node involvement, and local or distant metastasis, by two radiologists, who established a consensus.
CT and MR images depicted all tumors as large, ill-defined, relatively well enhancing, broad-based polypoid intramural masses with (n=3) or without (n=3) cystic portions. Their frequent location was posterior and trigonal (n=3). Calcification was found within one tumor, and lymphadenopathy in four. At T2-weighted MR images, the solid portion of the tumor was relatively hypointense. The stage at the time of diagnosis was C in three patients, and D1 in three. Follow-up imaging showed brain metastasis in one patient and liver metastasis in two.
On CT and MR images, SCC of the urinary bladder appeared as a large, enhancing, broad-based polypoid mass. It was stage C or higher, and lymph nodes and distant metastasis were frequent. T2-weighted MR images showed that the solid portion of the tumor was relatively hypointense. When radiologic examinations demonstrate a bladder tumor of this kind in adults, SCC of the urinary bladder should be included in the differential diagnosis.
原发性小细胞癌（SCC）是膀胱罕见的侵袭性恶性肿瘤，其组织病理学与肺癌相同。膀胱SCC的治疗和预后与更常见的移行细胞癌有所不同。本研究的目的是分析膀胱SCC的CT和MR成像表现。
本研究纳入了6例经病理证实为膀胱SCC的成年患者（5例男性，1例女性），这些患者均接受了盆腔CT和/或MR成像检查。由两位放射科医生对影像学表现进行回顾性评估，内容包括肿瘤位置、质地、钙化、浸润深度、膀胱周围侵犯、淋巴结受累情况以及局部或远处转移情况，并达成共识。
CT和MR图像显示所有肿瘤均为大的、边界不清、相对强化良好、基底较宽的息肉样壁内肿块，其中3例有囊性成分，3例无囊性成分。它们常位于膀胱后部和三角区（3例）。在1例肿瘤内发现钙化，4例有淋巴结肿大。在T2加权MR图像上，肿瘤的实性部分相对呈低信号。诊断时3例患者为C期，3例为D1期。随访成像显示1例患者有脑转移，2例有肝转移。
在CT和MR图像上，膀胱SCC表现为大的、强化的、基底较宽的息肉样肿块。它为C期或更高分期，且常伴有淋巴结和远处转移。T2加权MR图像显示肿瘤的实性部分相对呈低信号。当影像学检查显示成人膀胱有此类肿瘤时，应将膀胱SCC纳入鉴别诊断。
