Recent advances in the diagnosis of rectal cancer and evaluation of clinical treatment efficacy using magnetic resonance imaging

Accurate preoperative tumor staging is essential for precise treatment of rectal cancer, and magnetic resonance imaging (MRI) is the preferred method. In addition to accurately determining tumor (T) and stages node (N), MRI can also be used to evaluate factors related to the prognosis of rectal cancer, such as depth of tumor invasion into the muscular layer, extramural vascular invasion of the tumor, and distance to the circumferential resection margin. MRI is also an important method for evaluating tumor regression after neoadjuvant therapy, and quantitative biomarkers of functional MRI can objectively reflect treatment efficacy. Moreover, MRI can predict response after neoadjuvant therapy, local recurrence rate, and disease-free survival before treatment. The present article reviews recent advances in the preoperative diagnosis and staging of rectal cancer, reassessment after neoadjuvant therapy, and evaluation of clinical treatment efficacy using MRI.