Overall, patients with mCRC and isolated peritoneal carcinomatosis did not benefit when hyperthermic intraperitoneal chemotherapy was added to surgery.
Heated abdominal chemotherapy does not improve survival in patients with metastatic colorectal cancer who undergo abdominal cytoreductive surgery for isolated peritoneal carcinomatosis, and in fact was associated with a higher rate of late side effects in these patients, according to findings from the phase III PRODIGE-7 clinical trial. The study results (abstract LBA3503) were presented at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting, held June 1–5 in Chicago.
However, patients with more peritoneal disease might benefit from hyperthermic intraperitoneal chemotherapy (HIPEC), a subgroup analysis suggested.
“The addition of HIPEC with oxaliplatin does not influence survival results,” said lead study author FrancÌ§ois Quenet, MD, of the Regional Cancer Institute in Montpellier, France. “This is the first randomized study assessing the role of this special type of chemotherapy in advanced colorectal cancer, and it shows that it does not provide added benefit over surgery.”
Survival rates were “unexpectedly high” among patients who underwent surgery alone, Quenet noted. “Every colorectal cancer patient with an isolated peritoneal carcinomatosis should be considered for surgery,” he said. “HIPEC with oxaliplatin may be beneficial for patients with a medium amount of disease in the peritoneal cavity.”
HIPEC has been used for more than 15 years as a standard component of cytoreductive surgery for isolated peritoneal carcinomatosis, but it had not previously been known whether or not some patients could safely forego HIPEC.
Between February 2008 and January 2014, French researchers enrolled 265 patients with stage IV colorectal cancer and isolated peritoneal carcinomatosis (metastatic tumors in the abdominal peritoneum that are seen in 20% of patients with colorectal cancer). All patients underwent surgical cytoreductive resection and systemic chemotherapy for 6 months; 133 patients also received HIPEC, while 132 did not.
The 30-day postsurgical mortality rate was 1.5% in both groups. Postsurgical side effects were equivalent during the first 30 days after surgery, but by 60 days, complication rates were almost twice as high for patients who had undergone HIPEC (24% vs 13.6%; P = .03).
Median recurrence-free survival was 11.1 months in the non-HIPEC group and 13.1 months in the HIPEC group, a statistically nonsignificant difference.
Median overall survival (OS) was 41.2 months among patients who did not undergo HIPEC, and was 41.7 months among those who did. The 5-year OS rate was 87% for patients undergoing HIPEC and 88% among patients who did not receive HIPEC.