Prediction and evaluation value of functional imaging technique in neoadjuvant chemoradiotherapy of locally advanced rectal cancer

Abstract

For locally advanced rectal cancer, neoadjuvant chemoradiotherapy, followed by surgery and postoperative adjuvant chemotherapy has become a standard treatment mode. Neoadjuvant chemoradiotherapy can induce the tumors to shrink to different extent. Partial patients can obtain complete remission validated by postoperative pathological examination, which contributes to increasing the probability of radical surgery for rectal cancer patients, reducing the recurrence rate and improving the long-term clinical prognosis. In recent years, the prediction and evaluation of the clinical efficacy of neoadjuvant therapy has captivated widespread attentions from clinicians. In terms of imaging methods, conventional morphological imaging techniques cannot accurately assess the clinical efficacy of neoadjuvant chemoradiotherapy, whereas DWI-MRI, DCE-MRI, PET-CT and other functional imaging techniques can not only reflect the degree of tumor shrinkage, but also reveal the changes in the functional metabolism of tumors before and after treatment and yield higher accuracy. In this article, recent application of imaging techniques in the evaluation of clinical efficacy of neoadjuvant chemoradiotherapy for rectal cancer was reviewed. Key words: Rectal neoplasms/neoadjuvant chemoradiotherapy; Functional imaging; Prediction and evaluation