Colorectal cancer mimics: a review of the usual suspects with pathology correlation

Abstract

Colorectal cancer is the third most commonly diagnosed cancer in men and second most commonly diagnosed cancer in women worldwide. Initial diagnosis of colorectal malignancy is generally made on colonoscopy, sigmoidoscopy or digital rectal examination; however, with increased use of CT as primary investigation in patients with lower gastrointestinal symptoms, the diagnosis of colon cancer is often first apparent to a radiologist prior to more invasive tests. CT can demonstrate a discrete soft-tissue mass that narrows the colonic lumen or focal nodular wall thickening/stricture and a variety of pericolonic changes. Pattern of wall thickening has been described as an aid to differential diagnosis; however, significant overlap remains between primary colonic tumor and non-colonic tumors or benign conditions. Imaging is non-specific, and appropriate clinical history, direct inspection, histological analysis, and sometimes discussion at MDT are essential for accurate diagnosis and treatment planning. In this article, we will review the imaging features of some of these benign and malignant mimics of colorectal cancer, with accompanying histology slides where appropriate.

Carcinomas in inflammatory bowel disease: a narrative review on diagnostic imaging techniques

“…Additionally, MRI has a prominent role in the local staging of rectal cancer (25). With respect to CT imaging, there are distinctive patterns of wall thickening that allow to differentiate between a highly suspicious malignancy, that will appear as an irregular and heterogeneous focal thickening, whereas a symmetrical and homogeneous diffuse thickening will rather suggest the inflammatory location of IBD (26,27). However, this distinction is not always obvious, since A C B D in many cases of IBD, chronic and acute inflammatory processes coexist with some asymmetrical aspects that can confound the radiologist (26,27).…”

Localization of Colorectal Cancer Lesions in Contrast-Computed Tomography Images via a Deep Learning Approach

“…Although the CT imaging features of CRC have been well established, there is substantial overlap between the imaging presentations of benign and malignant colorectal diseases [ 14 ]. Moreover, broad-spectrum colonic complications such as colitis, perforation, or abscess formation can occur in patients with CRC, making it even more challenging to achieve a correct diagnosis [ 15 ].…”