Impact of peritoneal carcinomatosis in the disease history of colorectal cancer management: a longitudinal experience of 2406 patients over two decades

Background: Recent therapeutic developments demand for an update of information on natural history, risk factors and prognosis of peritoneal carcinomatosis (PC) of colorectal origin. Therefore, prospective registry data should provide information about incidence, predictors and outcome. Methods: From a prospectively expanded single-institutional database with 2406 consecutive patients with colorectal cancer (CRC), clinical, histological and survival data were analysed for independent risk factors and prognosis. Findings were then stratified to the era of treatment without chemotherapy, 5-Fluorouracil-only and contemporary systemic chemotherapy, respectively. Results: Overall, 256 (10.6%) patients were diagnosed with PC thereof 141 (5.85%) with metachronous PC. Independent risk factors for the development of metachronous PC were age <62 years, N2-status, T4-status, location of the primary in the left colon or appendix. In the era of contemporary systemic chemotherapy, prognosis for PC improved only not-significantly (median survival of 17.9 months vs 7.03 months, P = 0.054). Conclusion: Despite improvement in the overall outcome with prolonged median survival for the complete patient cohort with CRC, those patients with PC have not experienced the same benefit. In the era of contemporary systemic chemotherapy, progress in treatment resulted in only limited survival benefit. Thus, continuous efforts for further therapeutic advancements should be undertaken in these patients diagnosed with PC.