Can colorectal cancer that has spred to the abdominal cavity be cured?

This study evaluated whether patients with colorectal cancer and peritoneal carcinomatosis (cancer spread to the abdominal cavity) can be cured of their cancer using cytoreductive surgery and intraperitoneal chemotherapy.

Colorectal cancer or CRC (cancer of the large intestine) often spreads to the peritoneum (a sheath lining the abdominal cavity and covering the abdominal organs). This is called colorectal peritoneal carcinomatosis (CRPC). Because of the large surface of the peritoneum and the contact it has with the abdominal organs, all CRPC is usually difficult to completely remove. Therefore, surgeons perform a surgery called cytoreductive surgery or CRS to remove all visible cancer. This surgery is usually followed by an intraperitoneal chemotherapy or IPC, where the abdominal cavity is washed with a chemotherapy solution. This method is different from standard systemic (whole body) chemotherapy, where the chemotherapy drugs are injected into a vein and it is distributed to the whole body via the bloodstream. Although CRP with IPC has shown significant survival benefit in patients with CRPC over standard chemotherapy, it has not been established whether this treatment can represent a real cure for the disease. In an effort to predict cancer invasiveness, researchers used a list of risk factors called the peritoneal cancer index (PCI). A lower score means a lower extent of the cancer. A "cure" is usually defined as a patient surviving without any symptoms or signs of the disease (disease free survival or DFS) at least 5 years after the treatment. In this study, the authors evaluated the “cure” rate for CRS and IPC in patients with CRPC. 

107 patients with CRPC were selected for this study. All patients were underwent a complete CRS and IPC between 1995 and 2005 and were followed up for at least 5 years. Overall survival (defined as the percentage of patients who survived for a certain time after treatment with or without the disease) was 35% at 5 years and 15% at 10 years. 16% of patients were considered cured of the disease, after a DFS of at least 5 years. In addition, 13% of these patients never experienced a cancer recurrence. Surgery related complications occurred in 53% of patients, with a lower complication rate in the cured patients. A PCI score of 10 or less was associated with a higher overall survival (53%) compared to patients with a PCI between 10 and 20 (23%) or over 20 (12%). Other factors associated with a better cure rate were lower total surgery time, less blood loss during surgery, shorter hospital stay and fewer surgery complications.

In summary, the authors of this study showed that CRS and IPC can offer a cure in a selected group of patients with CRPC. These results are similar to cure rates for patients with CRC that has spread to other parts of the body (such as the liver) who have been treated with surgery. 

It is important to note that patients whose cancer was too extensive to be removed were not included in this study.

Ask your doctor about CRS and IPC and whether this is an appropriate treatment in your situation.