Translation of clinical trial outcomes to metastatic colorectal cancer patients in community practice

Aim: As multiple new agents have been added to the treatment options for patients with metastatic colorectal cancer, survival outcomes in clinical trials have continued to improve. Similarly, improved outcomes in routine clinical care would be anticipated, but have yet to be demonstrated. Here, we aim to explore whether survival gains demonstrated in clinical trials are reproducible in routine practice, and whether factors beyond new therapies may be contributing to improved outcomes. Methods: Comparison of comprehensive treatment and outcome data for consecutive patients diagnosed in 2003-2006 versus 2007-2010 at four specialist hospitals in Australia. Results: Data were available on 965 patients; median age 66.1 years (range 19-93), 572 (59%) were male. For the latter time period, there was an increase in patients receiving any treatment (74% vs 66%, P = 0.014), initial combination chemotherapy (57% vs 44%, P < 0.001) and bevacizumab (15% vs 2%, P < 0.001). There was no change in the percentage undergoing resection of distant metastatic disease. For the latter time period, overall survival was improved (median 24.8 vs 17.4 months, P < 0.001), including patients not receiving any active treatment (11.9 vs 6.4 months, P = 0.014). Conclusion: Survival outcomes in routine clinical care for patients with metastatic colorectal cancer have markedly improved in recent years following the introduction of multiple new active therapies. The improved outcome of untreated patients suggests earlier diagnosis and improved supportive care may also be contributing to survival gains.