Colonography by CT, MRI and PET/CT combined with conventional colonoscopy in colorectal cancer screening and staging

Abstract

Colorectal cancer (CRC) remains a leading cancer killer worldwide. But the disease is both curable and preventable at an early stage. Regular CRC cancer screening has been shown to reduce the risk of dying from CRC. However, the importance of large-scale screening is only now starting to be appreciated. This article reviews a variety of imaging procedures available for detecting ulcerative colitis (UC) and Crohn's disease (CD), polyps and CRC in their early stage and also presents details on various screening options. Detecting, staging and re-staging of patients with CRC also require multimodality, multistep imaging approaches. Staging and re-staging with conventional colonoscopy (CC), computer tomography colonography (CTC), magnetic resonance colonography (MRC) and positron emission tomography/ c o m p u t e r t o m o g ra p hy c o l o n o g ra p hy ( P E T / C TC ) are of paramount importance in determining the most appropriate therapeutic method and in predicting the risk of tumor recurrence and overall prognosis. The advantages and limitations of these modalities are also discussed.

Practice Parameters for the Management of Rectal Cancer (Revised)

“…in the case of an incomplete colonoscopy, a double-contrast barium enema 18 or Ct colonography may be used preoperatively. [19][20][21][22] if preoperative colon evaluation is not feasible, early postoperative evaluation (within 3 to 6 months) is reasonable. histological diagnosis should be confirmed before elective resection.…”

Demonstration of a sucrose-derived contrast agent for magnetic resonance imaging of the GI tract

“…However, colonoscopy is an invasive procedure that requires intravenous sedation and suffers from patient noncompliance. 3,4 CT colonography (CT-C) has high sensitivity to identify large polyps, but sensitivity decreases with a decrease in polyp size, 5 and radiation dosage is a concern. MRI colonography (MR-C) uses non-ionizing radiation and provides CRC lesion detection with high specificity, but modest sensitivity.…”

Dépistage organisé du cancer colorectal en France : Rôle de l’Institut National du Cancer

“…La coloscopie virtuelle consiste à réaliser une reconstruction tridimensionnelle du côlon suite à une acquisition à l'aide d'un scanner multidétec-teurs [12]. Elle ignore les lésions planes.…”