Comparing two chemotherapy drugs for cancer that has spread to the peritoneum

This study compared the outcome of patients with colorectal or appendix cancer that had spread to the peritoneum (the lining of the abdominal cavity).

Peritoneal metastasis indicates that the initial cancer has spread to the peritoneum. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CS/HIPEC) is a treatment option for peritoneal metastasis. CS/HIPEC involves surgically removing the parts of the peritoneum affected by cancer and then bathing the abdominal cavity in heated chemotherapy.

Different chemotherapy drugs can be used to bathe the abdominal cavity, including oxaliplatin (Eloxatin) or irinotecan (Camptosar). It is not yet known whether treatment with oxaliplatin or irinotecan is more effective for patients with peritoneal metastasis. 

This study included 32 patients with colorectal or appendix cancer treated for peritoneal metastasis. Treatment involved removing parts of the peritoneum that were visibly affected by cancer and then bathing the abdomen in heated chemotherapy. 20 patients received oxaliplatin-based and 12 patients received irinotecan-based chemotherapy. The rate of complications and patient survival rates were assessed over 3 years.

The rate of survival after 2 years was 70% of patients who received oxaliplatin and 66.7% of patients who received irinotecan. After 3 years the rate of survival was 65% for patients who received oxaliplatin and 41.7% for patients who received irinotecan. There was also a trend towards better survival in the 11 patients with appendix cancer (72.7% survival after 3 years) compared to the 21 patients with colorectal cancer (47.6% survival after 3 years).

No patients died as a result of the surgery and there was no difference in the rate of complications after either treatment. 35% of patients who received oxaliplatin-based treatment suffered a severe complication compared to 33.3% of patients who received irinotecan-based treatment. The most common complications included fluid accumulation around the lungs (6.3%), intestinal blockage (6.3%), wound infection (3.1%), bleeding after the surgery (3.1%) and lung infection (pneumonia; 3.1%). 

The authors concluded that there was trend towards improved survival after oxaliplatin-based chemotherapy.

This study only included a small number of patients and it was based on patient records. More research is needed to ensure that these results are widely generalizable.