In 2005, the CT Colonography Reporting and Data System (C-RADS) was established to provide a means of classifying findings of CT colonography (CTC) and of applying the advantages of structured reporting to the setting of colorectal cancer screening.
CT Colonography Reporting and Data System (C-RADS)
|
Score |
Description |
|
Colorectal |
|
|
C0, inadequate study |
Inadequate preparation; inadequate insufflation |
|
C1, normal colon or benign lesion |
No polyp >/= 6 mm; recommend routine screening with CT colonography or colonoscopy in 5 years |
|
C2, intermediate polyp or indeterminate finding |
Polyps 6–9 mm, < 3 in number; recommend CT colonography polyp surveillance or colonoscopy with polypectomy |
|
C3, polyp, possibly advanced adenoma |
Polyps >/= 10 mm; >/= 3 polyps, each 6–9 mm; recommend colonoscopy with polypectomy |
|
C4, colorectal mass, likely malignant |
Lesion compromises bowel lumen, shows extracolonic invasion; recommend surgical consultation |
|
Extracolonic |
|
|
E0, limited examination |
Compromised by artifact; evaluation of extracolonic tissues severely limited |
|
E1, normal examination or anatomic variant |
No extracolonic abnormalities visible; no workup indicated |
|
E2, clinically unimportant finding |
Examples: simple liver or kidney cyst, cholelithiasis without cholecystitis; no workup indicated |
|
E3, likely unimportant, incompletely characterized |
Example: minimally complex or homogeneously hyperattenuating kidney cyst; workup may be indicated; dependent on specific clinical scenario |
|
E4, potentially important finding |
Examples: solid kidney mass, aortic aneurysm; workup generally indicated, but dependent on specific clinical scenario; communicate to referring physician as per accepted practice guidelines |
References:
- Yee J, Chang KJ, Dachman AH, Kim DH, McFarland EG, Pickhardt PJ, Cash BD, Bruining DH, Zalis ME. The Added Value of the CT Colonography Reporting and Data System. J Am Coll Radiol. 2016 Aug;13(8):931-5. [Medline]
- Pooler BD, Kim DH, Lam VP, Burnside ES, Pickhardt PJ. CT Colonography Reporting and Data System (C-RADS): benchmark values from a clinical screening program. AJR Am J Roentgenol. 2014 Jun;202(6):1232-7. [Medline]
- Zalis ME, Barish MA, Choi JR, Dachman AH, Fenlon HM, Ferrucci JT, Glick SN, Laghi A, Macari M, McFarland EG, Morrin MM, Pickhardt PJ, Soto J, Yee J; Working Group on Virtual Colonoscopy. CT colonography reporting and data system: a consensus proposal. Radiology. 2005 Jul;236(1):3-9. [Medline]
- Yee J, Dachman A, Kim DH, Kobi M, Laghi A, McFarland E, Moreno C, Park SH, Pickhardt PJ, Plumb A, Pooler BD, Zalis M, Chang KJ. CT Colonography Reporting and Data System (C-RADS): Version 2023 Update. Radiology. 2024 Jan;310(1):e232007. [Medline]
Created Jan 24, 2018.
Up-date Mar 2, 2026.
