Shinya Satoshi, Sasaki Takamitsu, Nakagawa Yoshifumi, Guiquing Zang, Yamamoto Fumio, Yamashita Yuichi
Department of Gastroenterological Surgery, Yamamoto Memorial Hospital, Imari, Saga, Japan.
Hepatogastroenterology. 2007 Jul-Aug;54(77):1378-81.
BACKGROUND/AIMS: Diffusion-weighted imaging (DWI) is already utilized in the important clinical diagnosis of brain ischemia and also for differentiating brain abscesses from metastatic brain tumors. Recent technical developments make DWI of the body feasible. Several studies have revealed the usefulness of DWI for the diagnosis of liver, ovary, parotid gland, kidney, and breast tumors. We herein present cases of gastric cancer detected by DWI and discuss the efficacy of DWI for the diagnosis of gastric cancer.
We performed DWI, enhanced computed tomography (CT) and endoscopic examinations on 15 patients with gastric cancer. MR examinations were performed using the 1.5-T imager (Toshiba). We measured the signal intensity in a series of DWI images and calculated the apparent diffusion coefficient (ADC) values in order to differentiate the tumors from normal tissues and inflammations. Two experienced radiologists evaluated the depth of tumor invasion into the gastric wall (tumor staging), the involvement of regional lymph nodes (nodal staging), and the presence or absence of metastasis (metastatic staging) on DWI and CT images according to the TMN classification system. TMN staging of each tumor was compared with the pathologic and surgical findings.
There were no differences between the DWI and the CT images regarding their abilities to detect advanced gastric cancer. However, DWI could detect peritoneal dissemination, liver metastasis, lymph nodes metastasis without any enhancement material more clearly than CT.
DWI is therefore considered to have the potential to be clinically effective for the evaluation of preoperative TMN staging of gastric cancer.
背景/目的：扩散加权成像（DWI）已用于脑缺血的重要临床诊断，也用于鉴别脑脓肿与脑转移瘤。近期的技术发展使体部DWI成为可能。多项研究已揭示DWI对肝脏、卵巢、腮腺、肾脏和乳腺肿瘤诊断的有用性。我们在此呈现通过DWI检测出的胃癌病例，并讨论DWI对胃癌诊断的效能。
我们对15例胃癌患者进行了DWI、增强计算机断层扫描（CT）及内镜检查。使用1.5-T成像仪（东芝）进行磁共振检查。我们在一系列DWI图像中测量信号强度并计算表观扩散系数（ADC）值，以区分肿瘤与正常组织及炎症。两名经验丰富的放射科医生根据TMN分类系统在DWI和CT图像上评估肿瘤侵犯胃壁的深度（肿瘤分期）、区域淋巴结受累情况（淋巴结分期）以及有无转移（转移分期）。将每个肿瘤的TMN分期与病理及手术结果进行比较。
在检测进展期胃癌方面，DWI和CT图像的能力无差异。然而，DWI能比CT更清晰地检测到无任何强化物质的腹膜播散、肝转移及淋巴结转移。
因此，DWI被认为在临床上有可能有效评估胃癌的术前TMN分期。
