GS4 - Global Management and Outcomes Patterns in Acute Colorectal Cancer: Results from APOLLO International Prospective Cohort Study

Purpose/Background: Colorectal cancer (CRC) often presents as an emergency in about a third of patients, with complications such as bowel obstruction and perforation being common. These emergency presentations are associated with increased rates of mortality and morbidity, negatively affecting the quality of life of the patients. The existing management guidelines are largely based on low-grade evidence and small cohorts, leaving a significant gap in understanding global practices concerning emergency presentations of colorectal cancer. The primary objective of this study is to explore the international variation in emergency presentations, management strategies, and short-term outcomes in patients with colorectal cancer.

Methods/Interventions: A prospective observational study was conducted across 216 hospitals in 39 countries, engaging over 2000 collaborators. Data were collected by collaborators over a six-week continuous period from January to June 2023. The cohort included adult patients with colon and/or rectal adenocarcinoma requiring acute hospital admission. Patients presenting for side effects of chemotherapy or radiotherapy, non-colorectal primary cancers, or elective resections were excluded from the study. The primary outcome focused on 90-day mortality, with secondary outcomes including 30-day mortality, complications, readmission rates, colonic stenting rates, and stoma reversal rates.

Results/Outcomes: The study encompassed 1414 emergency CRC presentations with a median age of 70 years, with males constituting 54% of the cohort. The cancer characteristics revealed 83% colonic and 17% rectosigmoid/rectal presentations, with a high proportion being in advanced stages. The most common reason for acute presentation was bowel obstruction. Surgical intervention was employed in 72.3% of the cases. Within the surgical interventions, curative surgery was performed in 67.6% and palliative surgery in 32.4% of the cases. The length of hospital stay was slightly higher in the palliative group, with 11 days (IQR: 7 to 18), compared to the curative group, with 10 days (IQR: 7 to 15), with a p-value of 0.034. The curative group had a 90-day readmission rate of 10.4% (60 cases), a 90-day Clavien Dindo complication rate of ≥ 3 in 14.1% (96 cases), and a 90-day mortality rate of 7.5% (52 cases). On the other hand, the palliative group had a higher 90-day readmission rate of 15.4% (34 cases), a significantly higher 90-day Clavien Dindo complication rate of ≥ 3 in 31.2% (99 cases), and a notably higher 90-day mortality rate of 27.2% (90 cases). Among the non-operative cases, colonic stenting was performed in 4.0%. Notably, 23.2% of patients presenting acutely were either awaiting surgery or undergoing neoadjuvant therapy. There was a significant variation in overall mortality across countries but not in surgical mortality.

Conclusion/Discussion: This extensive international study reveals that over half of the acute CRC, presentations are due to large bowel obstructions, and around a quarter of these presentations occur in patients awaiting elective surgery or undergoing neoadjuvant therapy. The acute surgical mortality rate stands at a concerning 16% at 90 days. Despite the variations in overall mortality among different countries, the surgical mortality rates were consistent, underlining a need for further investigation and potentially an international consensus on managing acutely presenting CRC patients.