CHICAGO—Laparoscopic surgery does not appear to change the odds of survival compared with open surgery in the treatment of liver metastases in patients with colorectal cancer, according to the randomized OSLO-COMET trial (abstract LBA3516). The results were presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting, held May 31–June 4 in Chicago.
“A recent survey showed that only 22% of United States patients who contract liver metastases and who have surgery for it have laparoscopic surgery. Our trial is the first to compare laparoscopic and liver surgery for colorectal metastases,” lead study author Åsmund Avdem Fretland, MD, who is a surgeon in the Intervention Centre and the Department of HPB Surgery at Oslo University Hospital, Norway.
Colorectal cancer is one of the top four cancers in the United States, with 160,000 cases occurring each year; 50% of patients develop liver metastases. Fretland said in the current investigation, laparoscopic liver surgery had a lower rate of post-operative complications, led to an improved quality of life, and was cost-effective compared with open-liver surgery. After many years of improvements in laparoscopic surgery, there are now data that survival is as good with a laparoscopic approach as with open surgery, he added.
The first report of laparoscopic liver surgery was in 1991, but until this study, no one had looked at long-term outcomes in cancer that has metastasized to the liver in a randomized trial, according to the researchers. For this investigation, 280 colorectal cancer patients with liver metastases were randomly assigned to either laparoscopic surgery (n = 133) or open surgery (n = 147). The procedures were performed between February 2012 and January 2016, and about 50% of the patients received chemotherapy before or after their surgery, following standard Norwegian guidelines. The chemotherapy regimens were 5-fluorouracil plus leucovorin (folinic acid) and oxaliplatin.
Not all patients have been observed for a full 5 years yet, but based on ongoing outcomes, the researchers found patients who had the laparoscopic procedure lived a median of 80 months after surgery compared with 81 months for those who had open surgery. With the laparoscopic procedure, the median recurrence-free survival (RFS) was 19 months compared with 16 months for those who had open surgery. With a minimum of 3 years of follow-up, the researchers were able to estimate that 56% of patients who had open surgery would be alive 5 years after their procedure compared with 57% of those who had laparoscopy.
The findings also showed that an estimated 31% of patients who had open surgery would have no recurrence of disease 5 years later compared with 30% of those who had laparoscopy. There were no differences found between the groups in terms of the rate of complete tumor removal or the amount of tissue removed beyond the observable tumor. Patients who had laparoscopy reported improved health-related quality of life and had fewer post-operative complications (19% with laparoscopy vs 31% with open surgery) and the hospital stay was half as long (2 days vs 4 days).
Fretland and colleagues are now using artificial intelligence, genetic, and digital image analyses to better investigate the findings with the hope of improving the diagnosis and treatment of future patients. “We hope these results will encourage more hospitals to establish a laparoscopic liver surgery program. This has to include structured training of the surgeons,” said Fretland.