Chemotherapy in advanced colorectal cancer: prolongation of life or quality of life improvement?

In the paper ‘Quality of Life versus Prolongation of Life in patients treated with chemotherapy in advanced colorectal cancer: a review of randomized controlled clinical trials’ (de Kort, et al , Eur J Cancer, 2006; 42: 835-45) we have aimed to investigate whether the authors of research papers about chemotherapy in advanced colorectal cancer mainly strive for either prolongation of life or quality of life improvement. Oncologists often disagree about the main purpose of different chemotherapeutics in this non-curative setting. In order to answer this question we analyzed randomized controlled clinical trials that included an HRQoL assessment in colorectal cancer to see on which kind of outcome measures the authors based their final conclusions whether to use the experimental arm as a new standard.  

We found that prolongation of life is by far the most important outcome measure for the authors to base their conclusions on. This is important to realize because the results and interpretation of RCTs are for a large part the basis of physicians’ clinical decision-making. Another important finding was that QoL assessments were not very discriminating between the experimental and control arm and that the QoL outcomes were not related to toxicity outcomes at all. This makes it questionable whether the authors of the trial papers can justify the high toxicity found in most experimental arms by referring to often not significantly different QoL outcomes.  

This critical review can be helpful for oncologists and researchers who interpret and perform RCTs as they may become more aware of what they would consider as the main outcome of specific chemotherapeutic treatment options in advanced cancer. 

Besides the above mentioned paper we also work on other questions by qualitative research methods : 1) what kind of 'multiple steps' are shaping the treatment course in the day-to-day practice of advanced cancer when one-off decisions by the patient seldom take place (paper ready for submission), 2) how do physicians view their role in considering costs of expensive new disease-modifying treatments (paper ready for submission), and 3) which value judgements are made in guideline development for palliative chemotherapy, related to outcome measures and cut-offs (work in progress).

Susanne de Kort

General Practice Department, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands