Early diagnosis of colon cancer with computer-aided multi-energy CT colonography

描述(申请人提供)：结肠癌是美国男性和女性癌症死亡的第二大原因，如果检测到并移除前驱结肠病变，结肠癌是可以预防的。计算机体层摄影(CTC)，也称为虚拟结肠镜(VC)，可以显著提高结直肠检查的容量、安全性和患者的依从性。CTC已被美国癌症协会、美国多社会工作组和美国放射学会最近的指南批准为结直肠癌筛查的可行选择。计算机辅助检测(CAD)辅助的无泻剂粪便标记CTC是一种新兴的CTC技术，用于消除肠道清洁中的泻药或引起腹泻的高渗透造影剂。最近的一项大型多中心临床试验表明，将无泻剂制剂与口服造影剂和CAD相结合是可行的，可以使患者更容易接受CTC检查，同时以与光学结肠镜(OC)相当的灵敏度检测E10 mm大小的息肉。然而，非息肉样扁平病变和小息肉(6-9毫米大小)是假阴性研究的重要来源。因此，本项目的目标是开发一种新型的基于meCTC的CAD方案，称为多能量CAD(MeCAD)方案，以克服基于单能量CTC的CAD方案的局限性。我们假设，meCAD方案将(1)在检测息肉状和非息肉样结直肠病变方面产生与OC相当的高性能，(2)提高放射科医生在泻药中检测临床上有意义的结直肠病变的性能 超低剂量的免费meCTC图像。我们的具体目标是：(1)建立临床超低剂量meCTC图像数据库，用于meCAD方案的开发和评估；(2)开发一种新的meCAD方案，有效地检测超低剂量、无泻剂的meCTC图像中的结肠病变；(3)评估meCAD方案的临床效益。MeCAD方案的成功开发和验证将为放射科医生提供准确可靠的非侵入性CTC筛查方案，以早期发现和诊断结直肠病变，预防结直肠癌的发生。

DESCRIPTION (provided by applicant): Colon cancer, the second leading cause of cancer deaths for men and women in the United States, is preventable if precursor colonic lesions are detected and removed. Computed tomographic colonography (CTC), also known as virtual colonoscopy (VC), could substantially increase the capacity, safety, and patient compliance of colorectal examinations. CTC has been endorsed as a viable option for colorectal cancer screening by the recent guidelines of the American Cancer Society, U.S. Multi-Society Task Force, and the American College of Radiology. Laxative-free fecal-tagging CTC assisted by computer-aided detection (CAD) is an emerging CTC technique for eliminating of laxative agents or diarrhea-inducing high-osmolar contrast agents from bowel cleansing. A recent large-scale multi-center clinical trial suggests that the combination of laxative-free preparation with ingestion of oral contrast agent and CAD is feasible in making CTC examinations easy for patients to tolerate while detecting polyps e10 mm in size at sensitivity comparable to that of optical colonoscopy (OC). However, non-polypoid flat lesions and small polyps (6-9 mm in size) represent a significant source of false-negative studies. Thus the goal of this project is to develop a novel CAD scheme based on meCTC, denoted as a multi-energy CAD (meCAD) scheme, which overcomes the limitations of the CAD schemes based on single-energy CTC. We hypothesize that the meCAD scheme will (1) yield a high performance in the detection of both polypoid and non-polypoid colorectal lesions comparable to OC, and (2) improve radiologists' performance in the detection of clinically significant colorectal lesions in laxative free meCTC images at an ultra-low-dose. Our specific aims are (1) Establish a clinical ultra-low-dose meCTC image database for development and evaluation of a meCAD scheme; (2) Develop a novel meCAD scheme that effectively detects colorectal lesions in ultra-low-dose laxative-free meCTC images; (3) Evaluate clinical benefit of the meCAD scheme. Successful development and validation of the meCAD scheme will provide radiologists with an accurate and reliable non-invasive CTC screening scheme for early detection and diagnosis of colorectal lesions to prevent the occurrence of colorectal cancer.