Prognostic impact of postoperative intra-abdominal infections after elective colorectal cancer resection on survival and local recurrence: a propensity score-matched analysis

PURPOSE

Several authors have reported an association between anastomotic leak and/or intra-abdominal abscess and oncological survival and recurrence. However, no reports have investigated whether combining anastomotic leak/intra-abdominal abscess and positive drainage culture influences long-term oncological outcomes. Therefore, we defined these complications as postoperative intra-abdominal infections. The present study aimed to evaluate the prognostic impact of postoperative intra-abdominal infections on long-term oncological outcomes after curative stage I-III colorectal cancer surgery.

METHODS

We performed a retrospective analysis of 755 consecutive patients with stage I-III colorectal cancer undergoing curative surgery between 2010 and 2015 by performing a propensity score-matched analysis to reduce selection bias.

RESULTS

Of the 755 patients, 62 were matched for postoperative intra-abdominal infections analyses. The median follow-up was 48 months. Compared with the non-infections group, the postoperative intra-abdominal infections group had a significantly shorter local recurrence-free survival (P = 0.01 prior to matching, and P = 0.05 after matching). No significant difference was found between the groups in terms of overall, cancer-specific free, recurrence-free, or distant recurrence-free survival. However, multivariate analyses identified postoperative intra-abdominal infections as an independent prognostic factor for local recurrence-free survival (P = 0.04 prior to matching, and P = 0.03 after matching).

CONCLUSIONS

In this matched-pair analysis comparing stage I-III colorectal cancer patients with and without postoperative intra-abdominal infections, postoperative intra-abdominal infections were associated with poor local recurrence-free survival, but not overall, cancer-specific free, recurrence-free, or distant recurrence-free survival.

Procalcitonin and C-reactive protein as early markers of postoperative intra-abdominal infection in patients operated on colorectal cancer

PURPOSE

The aim of this study was to evaluate the accuracy of serum procalcitonin (PCT) and C-reactive protein (CRP) for early diagnosis of postoperative intra-abdominal infections (PIAI) after elective surgery for colorectal cancer.

METHODS

Prospective observational study including patients operated on for colorectal cancer between January and December of 2015 was performed. Serum PCT and CRP levels were measured before surgery and daily until postoperative day 3.

RESULTS

One hundred twenty patients were included. Seven patients (5.8%) had PIAI. PCT levels were significantly higher in patients with PIAI on postoperative days 1 and 3, whereas CRP levels only were significantly more elevated on postoperative day 3. The ratio between CRP levels on postoperative day 3 and CRP levels on postoperative days 2 (CRP D3/CRP D2) and 1 (CRP D3/CRP D1) was significantly higher in patients with PIAI. PCT on postoperative day 3, for a cutoff of 0.45 ng/mL, had the best sensitivity (100%) with a specificity of 73.8%. The ratio CRP D3/CRP D1 yielded the higher specificity and positive predictive value (90.9 and 27.3%, respectively, for a cutoff of 1.8). The higher negative predictive value was obtained for PCT on postoperative days 1 and 3 (100%, with cutoff of 0.76 and 0.45 ng/mL, respectively) and for CRP on postoperative day 3 (100% with cutoff of 10 mg/dL).

CONCLUSION

PCT and CRP serum levels are associated with the appearance of PIAI after colorectal cancer surgery, although the positive predictive values were low for both PCT and CRP. However, the negative predictive values were high.