Population-based survival of patients with peritoneal carcinomatosis from colorectal origin in the era of increasing use of palliative chemotherapy

BACKGROUND: Palliative chemotherapy improves survival in patients with metastasised colorectal cancer. However, there is a lack of data regarding the effectiveness of modern chemotherapy in patients with isolated peritoneal carcinomatosis (PC).

PATIENTS AND METHODS: All patients with synchronous PC of colorectal origin diagnosed in the Eindhoven Cancer Registry registration area between 1995 and 2008 were included (N = 904). We assessed the use of chemotherapy and overall survival in three time periods related to the availability of different chemotherapy regimens.

RESULTS: Chemotherapy use gradually increased over time. Median survival (MS) for patients with PC without other metastases diagnosed in 1995-2000 was 35 weeks [95% confidence interval (CI) 24-43] and 34 weeks (25-54) in 2005-2008. MS in patients diagnosed with PC plus other metastases was 21 weeks (15-27) in 1995-2000 and 26 weeks (18-33) in 2005-2008. In multivariable regression analysis, use of chemotherapy had a beneficial influence on survival only in 2005-2008. In the first two periods, chemotherapy treatment did not decrease the risk for death.

CONCLUSION: Despite increasing usage of palliative chemotherapy and availability of new agents, population-based survival of patients with PC did not improve until very recently. Response to palliative chemotherapy in PC should be evaluated separately from haematogenous metastases.