Background:
Anastomotic leak is a significant concern following rectal cancer surgery, often attributed to ischemic events during surgery. Preoperative ischemic conditioning through embolization of the inferior mesenteric artery may improve colonic perfusion. However, the cellular mechanisms underlying this ischemic preconditioning remain unclear.
Methods:
This ancillary study aimed to explore the cellular correlation of ischemic preconditioning through carbonic anhydrase IX (CAIX) expression in patients undergoing rectal cancer surgery. Normal colonic tissues from ten patients, five with ischemic preconditioning and five controls, were stained against CAIX. The number of intestinal crypts exhibiting CAIX fixation was quantified and compared between the two groups. The resistive index (RI) at the time of surgery and the complications during the 2-year follow-up were also reported.
Results:
Patients who underwent ischemic preconditioning demonstrated a significantly smaller decrease in RI values (p = .03) and less pronounced CAIX fixation compared to controls, although without statistical significance (p = 0.42). CAIX staining was significantly lower in patients without a significant decrease in RI (p = 0.04). Patients with a significant decrease in RI and marked increase in CAIX exhibited a higher rate of complications and lower rate of digestive continuity restoration.
Conclusion:
This study suggests a potential correlation between CAIX expression and RI drop in patients undergoing rectal cancer surgery, indicating a role for CAIX as a cellular marker of ischemic preconditioning. Ischemic preconditioning by early embolization may reduce CAIX expression, suggesting a protective effect on ischemic tissue.
Clinical trial: NCT03628248, 2021-08-04