Is follow‐up CT imaging of the chest and abdomen necessary after preoperative neoadjuvant therapy in rectal cancer patients without evidence of metastatic disease at diagnosis?

Abstract

Patients with rectal cancer often undergo multiple CT scans prior to surgical resection. We propose that in patients with locally advanced rectal cancer without evidence of metastatic disease at presentation, CT imaging of the chest and abdomen after preoperative neoadjuvant therapy does not change clinical information or surgical management. An institutional review board-approved medical record review identified patients with contrast enhanced CT of the chest, abdomen and pelvis alone or in conjunction with (18)F-fluoro-2-deoxy-d-glucose/positron emission tomography imaging for staging of rectal cancer prior to and after neoadjuvant therapy. Eighty-eight patients were included in the study. Scans were reviewed for the presence of metastatic disease on initial and follow-up imaging prior to surgical resection. Seventy-six (86%) of 88 patients had no evidence of metastasis at presentation. None of these patients developed metastatic disease after neoadjuvant therapy. Twelve (14%) had metastases at presentation. No study patient developed metastatic disease in a new organ. Imaging after preoperative neoadjuvant therapy in rectal cancer does not change the designation of metastatic disease. Patients with locally advanced rectal adenocarcinoma without evidence of metastases may not benefit from repeat imaging of the chest and abdomen after neoadjuvant therapy.