Day 2 CRP Identifies Lower Leak Risk After Colon Cancer Resection

Earlier discharge within enhanced recovery pathways creates a need to assess anastomotic leak risk before postoperative day (POD) 3. This two-cohort, multicenter diagnostic accuracy study evaluated POD2 C-reactive protein (CRP) below 100 mg/L in patients undergoing elective colon cancer resection with primary anastomosis. The test and validation cohorts included 401 and 213 patients, respectively; anastomotic leakage was defined as Clavien–Dindo grade ≥3.

Leakage occurred in 4.0% of the test cohort and 4.7% of the validation cohort. POD2 CRP was below 100 mg/L in 240 (60%) and 97 (46%) patients, respectively. Leak rates in these groups were 1.3% and 1.0%, yielding negative predictive values of 98.8% and 99.0%. Among patients with CRP ≥100 mg/L, leak rates were 8.1% and 7.8%.

For patients with elevated POD2 CRP, a decline by POD3 further identified lower risk. In the combined cohort, a POD3/POD2 ratio below 1 had negative predictive values of 98.9% after minimally invasive surgery and 97.9% after open surgery. The authors estimated that the two-step strategy could support discharge by POD2 or POD3 for nearly 90% of patients, with leak risk near 1%. These diagnostic findings may inform discharge assessment but do not establish the safety of algorithm-directed discharge; a low CRP does not eliminate leak risk.