Molecular markers for targeted neoadjuvant rectal cancer therapy

Neoadjuvant chemoradiotherapy is the standard of care for locally advanced rectal cancer. While neoadjuvant chemoradiation has been demonstrated to improve oncological outcomes, there is a wide spectrum of responses to therapy. The ability to predict who will respond favorably or unfavorably to neoadjuvant therapy could prevent unnecessary morbidity and potentially lead to novel therapeutic targets. A number of individual biomarkers and multigene signatures have been investigated as potential means of predicting response to neoadjuvant chemoradiation. While promising, none of these predictive biomarkers have yet been introduced clinically. This review summarizes both individual and multigene biomarkers for rectal cancer response to neoadjuvant chemoradiation.