Transcriptomic profiles of patients’ peroperative samples developing colorectal anastomotic leak show distinct signature

Author(s):
Jasper van Praagh; Peter Olinga; Jacco de Haan; Wouter Nagengast; Rudolf Fehrmann; Klaas Havenga

Background:

Anastomotic leakage (AL) is a severe complication in about 10% of patients that undergo a colorectal resection with the creation of an anastomosis. AL is associated with prolonged hospital stay, reintervention, intensive care admission, permanent ostomies and even death. Many factors, like patients’ comorbidity and chronic use of immune suppressive agents, are associated with the development of AL. However, much remains unknown about the underlying biological processes involved in the development of AL. The aim of this study is to elucidate the biological processes behind the development of AL on the transcriptomic level.

Methods:

Samples of circular stapled anastomoses of the colon (i.e. the ‘donuts’) were collected from patients who participated in the C-seal trial. In this multicenter trial patients underwent an elective colorectal resection with the creation of an anastomosis. Primary endpoint of this study was AL requiring intervention. Gene expression profiles were created for the collected samples with the Illumina NextSeq500 sequencing platform. Differential gene expression analysis was performed with Deseq2 package (v1.21.22) in R (v3.4.3). On the ranked list of differentially expressed genes, gene set enrichment analysis (GSEA) was performed utilizing several databases from the Molecular Signature Database(MSigDB).

Results:

After quality control of extracted RNA and sequencing results, we continued analysis with 91 samples. Out of these samples, 22 samples were from patients that developed AL and 69 from patients that did not. Differential expression analysis showed that 533genes were significantly (P <0.05) upregulated and 1,655 downregulated in AL samples compared to non-AL samples. GSEA showed 46 significantly upregulated pathways in patients developing AL, mainly associated with energy metabolism. Moreover, 1,604 downregulated pathways were significantly downregulated, mainly associated with the immune system.

Conclusions:

This study shows differences in the colon tissue at transcriptomic level at the time of creation of the anastomosis between patients that develop AL and patients that do not. These results can be used for future (peroperative) identification of patients that are at risk for the development of AL. It can also be used to adjust peroperative or even preoperative treatment in order to reduce this serious adverse event.