Comparison of patient survival after treatment for colorectal cancer that has spread

This study investigated whether cancer that has spread to the peritoneal surface (the lining of the abdominal cavity) can be treated as effectively as cancer that has spread to the liver in colorectal cancer patients.

The liver is the most common metastatic site (site for the cancer to spread to) for colorectal cancer. Surgical removal of the affected liver (liver resection) is the best way to treat liver metastasis.

Another common location for the cancer to spread is the peritoneal surface. The best way to treat patients with peritoneal metastasis is with cytoreductive surgery plus hypertherpic intraperitoneal chemotherapy (CS/HIPEC). CS/HIPEC involves surgically removing affected parts of the peritoneum and then bathing the abdominal cavity in heated chemotherapy. It is unclear whether peritoneal metastasis can be treated as effectively as liver metastasis.

This study reviewed records of colorectal cancer patients who had liver surgery or CS/HIPEC. Liver resection was performed on 179 patients and 93 patients underwent CS/HIPEC. The completeness of the resection was graded R0 or R1. R0 indicated that all visible and microscopic evidence of tumor cells had been removed. R1 indicated that all visible tumors were removed but some microscopic evidence remained.

Overall, at the 5 year follow-up 36% of patients who had undergone liver surgery were still alive. The average patient survival time was 46 months. After 5 years, fewer patients who had undergone CS/HIPEC were still alive (26% of patients) and their average survival time was significantly less (34 months).

However, no differences in survival were found when patients were grouped based on their R0 or R1 status. Average survival time was 49 months for patients with R0 liver resection compared to 41 months for R0 CS/HIPEC patients. Average survival time was 28 months for R1 liver resection compared to 23 months for R1 CS/HIPEC patients. The rates of morbidity and mortality did not differ between both treatments.

The authors concluded that long-term survival is comparable between patients who undergo liver resection or CS/HIPEC if patients are grouped based on completeness of the surgery.