Purpose
Myocardial injury after noncardiac surgery (MINS) is associated with increased mortality and postoperative complications. In patients with colorectal cancer (CRC), postoperative complications are a risk factor for cancer recurrence and disease-free survival. This study investigates the association between MINS and long-term oncological outcomes in patients with CRC in an ERAS setting.

Methods
This retrospective cohort study was conducted at Zealand University Hospital, Denmark, between June 2015 and July 2017. Patients undergoing CRC surgery were included if troponin was measured twice after surgery. Outcomes were all-cause mortality, recurrence, and disease-free survival within five years of surgery.

Results
Among 586 patients, 42 suffered MINS. After five years, 36% of patients with MINS and 26% without MINS had died, p = 0.15. When adjusted for sex, age and UICC, the hazard ratio (aHR) for 1-year all-cause mortality, recurrence, and disease-free survival were 2.40 [0.93–6.22], 1.47 [0.19–11.29], and 2.25 [0.95–5.32] for patients with MINS compared with those without, respectively. Further adjusting for ASA status, performance status, smoking, and laparotomies, the aHR for 3- and 5-year all-cause mortality were 1.05 [0.51–2.15] and 1.11 [0.62–1.99], respectively. Similarly, the aHR for 3- and 5-year recurrence were 1.38 [0.46–4.51], and 1.49 [0.56–3.98] and for 3- and 5-year disease-free survival the aHR were 1.19 [0.63–2.23], and 1.19 [0.70–2.03].

Conclusion
In absolute numbers, we found no difference in all-cause mortality and recurrence in patients with and without MINS. In adjusted Cox regression analyses, the hazard was increased for all-cause mortality, recurrence, and disease-free survival in patients with MINS without reaching statistical significance.