Introduction Elevated post-operative inflammatory ratios have been associated with complications following colorectal surgery, and a reduction in cancer specific survival.^1,2No studies have previously evaluated the value of pre-operative inflammatory ratios in predicting post-operative complications

Method Consecutive rectal cancer resections in a tertiary referral centre were evaluated using prospectively maintained clinical databases, and review of clinical notes if required. Patients with post-operative septic complications (n = 54; 17=anastomotic leak; 13=flap/perineal wound complication; 21=pelvic collection; 3=wound complication/other) were compared to those with no such complications (controls; n = 161). Neutrophil-(NLR) and platelet-(PLR) lymphocyte ratios, C-reactive protein (CRP), haemoglobin and albumin were recorded pre- and post-operatively in each case, along with demographic and disease-specific data. Normally distributed data were compared with t-tests and expressed as mean [standard error of mean]. Non-parametric data were analysed using Mann-Whitney U tests (median [inter-quartile range]), and proportions compared with Fisher’s exact test. Correlations were assessed using Pearson’s correlation coefficient

Results Mean age at surgery was similar between groups (66 vs. 68 [controls] years; p=NS). Mean pre-operative PLR was significantly higher in the complication group (269.2 [22.8] vs. 186.3 [6.8]; p < 0.0001), as was the NLR (4.7 [0.5] vs. 3.2 [0.13]; p = 0.0002). The difference in post-op PLR (377.5 [33.2] vs. 297.6 [13.6]; p = 0.009) was significant, whilst a non-significant trend towards greater post-op NRL was seen in the complication group (15.6 [1.13] vs. 12.9 [0.72]; p = 0.065). Median post-op CRP was significantly higher in the complication group (127 [84–189] vs. 97 [56–139]; p = 0.012). There were no differences in pre- or post-operative albumin or haemoglobin between groups. Pre-op and post-op PLR have a better correlation (R=0.54) then NLR (R=0.36) in the complication groups. There were significantly more deaths (all causes) (7/54 [13%] vs. 7/161 [4.3%]; p = 0.049), disease-specific deaths (5/54 [9.3%] vs. 4/161 [2.5%]; p = 0.046) and disease-specific recurrence (11/54 [20.4%] vs. 14/161 [8.7%]; p = 0.028) in the complications group

Conclusion Pre-operative elevation of inflammatory cell ratios (NLR and PLR) are novel predictors of post-operative complications following surgery for rectal cancer, and may also predict poor cancer-specific outcomes. This data suggests that tumour biology holds an important influence over complications rather than technical factors alone

Disclosure of interest None Declared.

References

1. Cook EJ, Walsh SR, et al. Int J Surg. 2007;5(1):27–30

2. Proctor MJ, Morrison DS, et al. Eur J Cancer 2011;47(17):2633–41