Previous survival estimates of CRC after hepatic resection might have been overly optimistic

The short- and long-term survival estimates of patients undergoing hepatic resection might have been overestimated in prior studies of the surgical procedure, according to data taken from a national Medicare cohort.

The population-based study found a five-year survival rate of about 25.5% in Medicare beneficiaries compared with survival rates closer to 35% in two prior U.S. studies. The researchers found that extremely elderly patients and those undergoing synchronous colon and hepatic resection for metastatic colorectal cancer are at the highest risk for worse outcomes after surgery.

The researchers examined Medicare data in a national sample. HMO patients admitted to acute care hospitals between Jan. 1, 2000 and Dec. 31, 2004 with first-time primary diagnosis of colorectal cancer with resection were identified (n=306,061). Only patients who subsequently underwent hepatic resection for liver metastases were included (n=3,957); 40% were aged 75 years or older.

Crude 30-day mortality was 4% and 90-day mortality was 8.2%. Patients aged 80 years or older had a higher rate of 90-day mortality than those aged 65 to 69 years (15.8% vs. 5.4%). Similarly, patients who underwent synchronous resection had a mortality rate more than twice that of patients who underwent metachronous resection (13.3% vs. 5.8%).

Compared with patients who had the lowest Charlson score for comorbid illness, those with the highest score were 40% more likely to have died at 90 days (95% CI, 1.06-1.85).

Five years after hepatic resection, 25.47% of patients remained alive. According to the researchers, survival differed significantly across age levels. Increasing age, comorbid disease and synchronous hepatic resection were the most predictive factors of long-term mortality.

In an accompanying editorial, Jean-Nicolas Vauthey, MD, and Daria Zorzi, MD, of the department of surgical oncology at The University of Texas M.D. Anderson Cancer Center, addressed the importance of a multidisciplinary approach to the management of colorectal cancer liver metastases.

“Their study is important because it demonstrates that the results of liver resection in these Medicare patients were worse than current results from units that have surgical expertise,” they wrote. “The authors’ data suggest that disease site-oriented programs to improve outcomes nationally are warranted. Delivering a high standard of care with up-to-date expertise remains critical in this rapidly evolving field.”

Cancer. 2009;doi: 10.1002/cncr.24081.