Treatment of Metastatic Colorectal Cancer: Standard of Care and Future Perspectives.

Palliative chemotherapy for metastatic colorectal cancer has undergone substantial changes in recent years. The implementation of modern biologicals in the treatment has substantially improved overall survival up to 30 months. With the increasing number of therapeutic options, the question of optimal treatment sequence arises, which is addressed in current studies like FIRE 4 or STRATEGIC-1. Furthermore, clinical and molecular biomarkers to predict efficacy and tolerability are urgently needed. Today, the detection of activating RAS mutations is the only validated biomarker which precludes patients from anti-EGFR treatment. The detection of BRAF mutation V600E is associated with a very poor prognosis corresponding to a survival of 9-12 months. Prospective trials evaluating an optimal approach to this subgroup are still missing. First results from strategies targeting the aberrant signal transduction are promising and require further validation. Despite the advances so far, life expectancy unfortunately continues to be limited in the majority of patients with metastatic colorectal cancer. New strategies are needed to improve the prognosis. To this end, the identification of Her2/neu as a potential target and first experiences with checkpoint inhibition in patients with mismatch repair-deficient tumors are promising and also require further validation.