Colorectal Cancer Survivorship: Steps towards integrative oncology and patient-centered cancer care

Abstract

In the Netherlands, 1 in 20 people develop colorectal cancer. A healthy lifestyle plays an important role in the prevention of colorectal cancer. Even after diagnosis, disease outcomes partially depend on lifestyle habits. This means that patients themselves can contribute to a better survival and quality of life. Besides the existing knowledge that loss of muscle mass is associated with worse treatment outcomes, we have shown that muscle mass loss is also related to a reduced quality of life in patients with metastatic colorectal cancer. In addition, we identified multiple factors associated with the occurrence of muscle loss, including higher muscle mass prior to therapy, longer time to diagnosis of metastases, and active smoking behavior. Furthermore, it is known that patients who continue to smoke after diagnosis experience more treatment-related side effects and have a reduced survival. Despite these negative effects, only a minority of oncologists in Europe actively provide support in smoking cessation. This could potentially be improved by focusing on the most commonly identified barriers, such as lack of time, resources and training. These results together support a patient-centered integrative oncology program in which patient-specific factors are taken into account to improve treatment outcomes. In this thesis we also evaluated the Dutch Colorectal Cancer (PLCRC) cohort by investigating whether participating patients are representative of the entire Dutch group of patients with colorectal cancer. This is relevant since representative population-based data can be used to better evaluate existing and new treatments that are given in daily practice.