title: Revisiting the potential signs of colorectal cancer on contrast-enhanced computed tomography without bowel preparation.
abstract: Colorectal cancer (CRC) is the second most common cause of cancer death in the US. Earlier detection can allow treatment with curative intent and improve prognosis. Optical and virtual colonoscopy are widely used in screening for colonic polyps and in the investigation of suspected CRC. However, contrast-enhanced computed tomography (CT) is still performed to investigate various non-specific abdominal complaints. Hence, a significant number of CRC are identified on contrast-enhanced CT without bowel preparation. We describe several signs, which when present in tandem, raise suspicion of CRC, and may warrant further investigation with optical colonoscopy. These include an intraluminal mass, eccentric or circumferential wall thickening >3 mm, focal wall enhancement, pericolic fat stranding, a cluster of >3 local lymph nodes, and enlarged lymph nodes >10 mm in short axis. Multiplanar evaluation of the bowel should be performed on all CT abdominal studies, including those without bowel preparation, to identify subtle features of CRC.
authors.affiliation: Royal Blackburn Hospital, East Lancashire Hospitals NHS Trust, Haslingden Road, Blackburn, Lancashire, BB2 3HH, United Kingdom. naqvi.jawad@gmail.com.
authors.forename: Jawad
authors.initials: J
authors.lastname: Naqvi
authors.affiliation: Royal Blackburn Hospital, East Lancashire Hospitals NHS Trust, Haslingden Road, Blackburn, Lancashire, BB2 3HH, United Kingdom.
authors.forename: Sharath
authors.initials: S
authors.lastname: Hosmane
authors.affiliation: Royal Blackburn Hospital, East Lancashire Hospitals NHS Trust, Haslingden Road, Blackburn, Lancashire, BB2 3HH, United Kingdom.
authors.forename: Snehal
authors.initials: S
authors.lastname: Lapsia
mesh_terms: D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D003287:Contrast Media; D006801:Humans; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media
keywords: Colonic neoplasms; Colorectal cancer; Multi-detector computed tomography