Routine preoperative restaging CTs after neoadjuvant chemoradiation for locally advanced rectal cancer are low yield: A retrospective case study

Introduction: Pre-operative restaging CT scans are often performed routinely following neoadjuvant chemoradiotherapy for locally advanced rectal cancer. There is a paucity of data on the utility of this common practice. We sought to determine how often restaging CTs identified disease progression or regression that altered management. Methods: We performed a single-institution retrospective study. From 2007 to 2011, 182 patients had newly-diagnosed, non-metastatic rectal adenocarcinoma, of which 96 were surgical candidates with clinical stage II/III disease. Ninety-one of these patients (95%) completed neoadjuvant chemoradiation. Results: Eighty-three out of 91 patients (91%) had restaging CTs. Four patients (5%) had new lesions suspicious for distant metastasis (2 lung, 2 liver) on restaging CT scan reports (1 of these was present on initial staging CT but not reported). All 4 patients had node-positive disease. In no case did restaging CT result in a change in surgical management. Discussion: Because of the financial costs and established risks of intravenous contrast and cumulative radiation exposure, it may be advisable to take a more selective approach to preoperative imaging. Larger, prospective studies may enable identification of an at-risk cohort who would benefit most from restaging CT. Conclusion: Routine restaging CT scans are low yield in the management of locally advanced rectal cancer.