Phase I study of intraperitoneal irinotecan combined with palliative systemic chemotherapy in patients with colorectal peritoneal metastases.

Patients with extensive colorectal peritoneal metastases who are not eligible for surgery and heated intraperitoneal chemotherapy have poor survival. The authors tried to improve the survival of these patients by adding intraperitoneal (inside the abdominal cavity) chemotherapy to standard palliative chemotherapy which is administered into the bloodstream. In this trial, irinotecan (a type of chemotherapy) was administered into the abdomen of patients with extensive colorectal peritoneal metastases. The authors investigated which dose could be administered safely in combination with standard palliative chemotherapy. They also looked into toxicity, safety, benefit, and movement of the drug in the body. Eighteen patients were treated in this study. The maximum tolerated dose of intraperitoneal irinotecan was 75 mg. It was well tolerated and could be administered safely. The intra-abdominal amount of irinotecan was high, whereas the amount of irinotecan in the blood remained low. The benefits of intra-abdominal irinotecan were promising. Because of this, a new study has been started to further investigate this new combination chemotherapy for colorectal cancer.