PALM BEACH, FLA. – Simultaneous and staged removal of primary colorectal cancer and associated liver metastases worked equally well, a review of more than 1,000 cases at four international centers has shown.
"Long-term outcome of patients with synchronous colorectal liver metastases is dictated by biology, not by surgical strategy," Dr. Timothy M. Pawlik, FACS, said at the annual meeting of the Southern Surgical Association.
About a quarter of patients with advanced colorectal cancer present with synchronous liver metastases, and surgeons have used three different resection strategies. The classic approach has been staged removal of the primary, colorectal cancer first, followed by removal of the liver disease in a separate operation at a later time. In a much smaller number of cases, the staged approach is reversed, with initial excision of the liver disease followed later by removal of the primary tumor. The third option has been to do both excisions during a single operation. Until now, assessments that compared these approaches mostly have used data from a single center, and in several cases the reviews included relatively few patients, said Dr. Pawlik, a surgical oncologist at Johns Hopkins University in Baltimore.
The review done by Dr. Pawlik and his associates involved 1,004 patients treated between 1982 and 2011 at four major hepatobiliary centers in the United States and Europe. The series included 647 patients treated by removal of their primary colorectal tumor followed by a second surgery to remove their liver metastases, 329 patients who had both excisions done during a single operation, and 28 patients who had their liver metastases removed first and then had the primary tumor removed in a second operation.
The data showed no statistically significant difference for any outcome measure, including the incidence of complications, 90-day mortality, local recurrences, median survival, or rate of 5-year survival. For example, during a median follow-up of 34 months, the recurrence rate was 57% among patients treated with a classic, staged approach and 60% among patients who had a simultaneous excision, a difference that was not statistically significant. And in a multivariate regression analysis of factors associated with mortality during follow-up, simultaneous excision linked with an 8% higher mortality rate relative to a classic staged approach, but again the difference was not statistically significant.
"Long-term survival was associated with the location and extent of disease, but not with the surgical strategy," Dr. Pawlik said.
But he also qualified these findings with a couple of caveats. First, the findings "should only be extrapolated to academic centers, major hepatobiliary centers. The findings cannot be extrapolated to the community setting," he said.
Second, he agreed with the discussants of his report that a prospective, randomized trial should be done to definitively prove that surgical strategy has no impact on outcomes.
Dr. Pawlik said he had no relevant financial disclosures.
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