Advances and challenges in treatment of locally advanced rectal cancer.

Dramatic improvements in the outcomes of patients with rectal cancer have occurred over the past 30 years. Advances in surgical pathology, refinements in surgical techniques and instrumentation, new imaging modalities, and the widespread use of neoadjuvant therapy have all contributed to these improvements. Several questions emerge as we learn of the benefits or lack thereof for components of the current multimodality treatment in subgroups of patients with nonmetastatic locally advanced rectal cancer (LARC).