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CT colonography reporting and data system

Dr Jeremy Jones and Dr Yuranga Weerakkody et al.

The CT colonography reporting and data system is a method devised to to standardise CT colonography reporting.

It primarily classifies abnomalrities into colonic (C) and extra-colonic (E)

Colonic classification

C0 : inadequate study
C1 : normal colon / benign lesion > routine screening to be continued
C2 : indeterminate polyp > surveillance or colonoscopy
- 6 - 9 mm in diameter
- < 3 in number
C3 : possibly advanced adenoma > follow up colonoscopy
- > 10 mm in diameter
- > 3 in number with each 6 - 9 mm
C4 : colonic mass likely malignant > urgert surgical referral
- has associated luminal narrowing
- has extra colonic extension

Extra-colonic classification

E0 : limited exam
E1 : normal exam or normal variant
E2 : clinically unimportant finding : simple liver cyst, verbral haemangioma > no work up required
E3 : likely unimportant or incompletely characterised finding : e.g minimally complex renal cyst > referal depends on local centre.
E4 : potentially important finding : e.g solid renal mass > communicate to referring physician