Synchronous vs Sequential Tumor Resection in Patients With Advanced Colorectal Cancer
About 20% of patients with colorectal cancer have cancers that have metastasized beyond the colon at the time of their diagnosis, with the liver being the most common site for these metastases. The approach to treating primary tumors within the colon and metastatic tumors in the liver continues to evolve, but it typically involves chemotherapy plus surgical resection of both types of tumors. However, experts continue to debate whether surgical resection of primary tumors and metastatic tumors should be performed synchronously or sequentially.
In an article published by Shubert et al in the Journal of Gastrointestinal Surgery, Mayo Clinic researchers provided a detailed comparison of patient outcomes associated with synchronous and sequential colorectal and liver resections in patients with stage IV colorectal cancer, identifying some benchmarks for surgical practice. According to the authors, the study results provide procedure-specific national benchmarks for postsurgical outcomes that will facilitate comparisons for quality improvement.
Study Design
In designing their study, the researchers used a large, multi-institutional database to identify a pool of 43,408 patients who underwent colorectal and liver resections for stage IV colorectal cancer. Before this study was conducted, only limited surgical outcome data were available for these patients.
“Our primary aim was to establish the magnitude of risk that each component operation, both liver and colon, contributed to synchronous resections in order to determine which combination of colon and liver operations were most safe to be performed at the same time,” said David Nagorney, MD, a general surgeon at Mayo Clinic.
Although past studies had only considered the extent of liver resection performed, Mayo researchers also reviewed the type or location of colorectal resection. “We wanted to test the hypothesis that both the extent of the liver resection and the location or type of colorectal resection influence the overall risk and patient outcomes associated with these operations,” said Christopher Shubert, MD, also a surgeon at Mayo Clinic.
The researchers assigned risk categories to each of the operations performed in the data pool, including colorectal and liver resections, and then compared 30-day postsurgical outcomes among patients within similar risk groups. They also compared outcome data between two groups of patients within each risk category—those who had synchronous colorectal and liver resections and those who had these operations sequentially.
“Stratifying patients using risk categories allowed us to make more accurate comparisons between patient outcomes associated with synchronous vs sequential resections,” said Dr. Shubert.
Findings
Analyzing data from patients within specific risk categories, researchers found major complications after synchronous liver and colorectal resections vary and are related to the extent of liver resection performed and the type of colorectal surgery performed. In addition, the risk for poor patient outcomes increased as the risk of each component surgical procedure increased. In other words, regardless of surgery timing, patients who require higher-risk procedures, such as a major liver resection due to the presence of larger or multiple metastatic tumors or high-risk colorectal resections, have poorer outcomes than those who underwent more minor surgery. Lastly, synchronous resection of primary colorectal tumors and metastatic liver tumors appears to be safe and effective in patients who require only minor liver resections.
“Our findings also show that performing preoperative risk assessments on patients who require both liver and colorectal resections could allow surgeons to more accurately predict patient outcomes and assist in preoperative planning and counseling these patients,” said Dr. Nagorney.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
