LAUSR

While the effect of immunosuppressive therapy on postoperative outcomes have been thoroughly evaluated in patients with inflammatory bowel disease, there are less outcome data in immunosuppressed patients undergoing surgery for colorectal cancer. Sims et al. [1] utilized the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to determine the effect of immunosuppression on 30day postoperative morbidity and mortality following surgery for colon and rectal cancer. As one might expect, the authors found an increased rate of 30-day postoperative morbidity and mortality in the group receiving immunosuppression. While this is useful information and captures a large number of patients, there are important limitations to the ACS-NSQIP database. First, the definition of ‘immunosuppression’ includes corticosteroids, immunomodulators and biologics. While we can assume that most of these patients are on corticosteroids, the database does not separate the patients into cohorts based on immunosuppressive type. From the literature in inflammatory bowel disease, we know that various immunosuppressives are more consistently shown to be higher risk for postoperative complications – corticosteroids are associated with increased postoperative morbidity [2,3], immunomodulators do not appear to increase risk of postoperative morbidity [4], and biologic therapy remains controversial [3,5,6]. Second, the definition of ‘immunosuppression’ does not, after 2011, include chemotherapeutic regimens which may contribute to perioperative complications. Third, there are no long term data to better understand if infectious complications or anastomotic leaks impact long term oncologic outcomes or stoma reversal rates. Despite these limitations, the authors point out that immunosuppression does increase morbidity, namely in the infectious complications as septic complications and surgical site infectious were increased while pulmonary, cardiovascular, renal, and neurologic complications remained unchanged. Therefore, holding immunosuppression, lowering doses, and having a lower threshold to divert low anastomoses may be warranted in patients undergoing abdominal surgery for colon and rectal cancer.