Changing prognosis of metastatic colorectal adenocarcinoma (mCRC) 1988-2008 within the general population: Has everyone benefitted?

Abstract

e14143 Background: Between 1991 and 2008 the FDA approved 7 new drugs for the treatment of mCRC. The results of randomized phase III trials, performed on selected (e.g. younger) patient populations, may not reflect net benefit seen within the general population. We therefore performed a population-based survival analysis of patients who initially presented with mCRC. Methods: Survival statistics were extracted from the Survival, Epidemiology and End Results (SEER) Database for patients diagnosed with mCRC between 1988-2008. Survival was analyzed using the Kaplan-Meier method and proportional hazard models as appropriate. Exclusion criteria included diagnosis at autopsy, non-adenocarcinoma and unknown histology. Results: The study population consisted of 42,347 patients diagnosed with mCRC from 1988-2008, 52% female. Mean age 67 years; 46% were aged 70 or over. Prognostic variables included race, gender, age, marital status, disease site, surgical resection and year of diagnosis (for all p<0.001). For the entire population median OS improved from 8 months in 1988 to 14 months in 2007. Net improvement in OS was highly dependant upon age: for pts<50 yr OS improved from 9m to 21m; for pts 50-69 yr from 10m to 17m; for pts >=70 yr from 7 to 8m. Conclusions: There has been a continuous improvement in OS of patients diagnosed with mCRC between 1988 and 2008. We could not determine if this was due to new therapeutic agents or improved imaging leading to earlier diagnosis. Little improvement has been seen in patients >70 years age. The disparity in median OS between younger and older patients with mCRC over this period has widened from 2 months in 1988 to 13 months in 2008.