Colorectal Cancer and Advanced Adenoma after Single CT Colonography or Biennial FIT Screening in the SAVE Randomized...

Area of Science:

• Gastroenterology
• Oncology
• Radiology

Background:

• Current guidelines recommend a 5-year screening interval for CT colonography (CTC) and a 2-year interval for fecal immunochemical tests (FITs) for colorectal cancer (CRC) screening.
• The natural history of CRC informs these recommended screening frequencies.

Purpose of the Study:

• To evaluate the appropriateness of the 5-year screening interval for CTC.
• To determine if CTC is associated with earlier CRC diagnosis compared to biennial FIT screening.

Main Methods:

• A secondary analysis of the SAVE randomized controlled trial involving 14,981 participants aged 54-65 years.
• Participants were randomized to either a single CTC examination or three biennial FITs.
• Cox regression models were used to compare CRC and advanced adenoma (AdA) incidence rates between groups after extended follow-up.

Main Results:

• No statistically significant difference in CRC incidence rates was observed between the CTC and FIT arms (adjusted hazard ratio, 0.73; P = .38).
• All stage IV CRCs (n=7) were diagnosed in the FIT arm.
• The CTC arm demonstrated a significantly higher incidence rate of advanced adenomas (AdA) compared to the FIT arm (adjusted hazard ratio, 1.46; P = .007).

Conclusions:

• The 5-year screening interval for CTC appears appropriate for colorectal cancer screening.
• CTC screening may be associated with earlier diagnosis of colorectal neoplasia compared to biennial FIT screening.