Pre-operative staging with positron emission tomography in patients with pelvic recurrence of rectal cancer

Background/Aim: The treatment of pelvic recurrences of rectal cancer is primarily surgical. The substantial morbidity and mortality of such resections warrant stringent patient selection. Recent literature reports PET to be of additional value to CT for the detection of metastases in colorectal cancer patients. We studied the clinical impact of PET in pelvic rectal cancer recurrence. Methods: PET findings in 37 pelvic recurrences of rectal cancer were evaluated retrospectively. Comparison was made to CT and MRI findings. It was analyzed whether PET had been decisive in clinical decision making or could have been so. Results: Thirty-two patients had 37 rectal cancer recurrences. PET differed from conventional imaging in 13 cases (35%): seven PET scans showed lesions that were not seen with CT or MRI. PET scans were negative in six lesions detected by CT or MRI. PET alone changed management in five recurrences (14%). Four PET scans were false-positive; this had clinical implications in 2 patients. Conclusion: In a selected population with pelvic rectal cancer recurrences, PET had additional value to conventional imaging, mainly in detecting lymph node metastases. PET findings thus had a significant impact on selection of patients for curative surgery. Copyright (C) 2008 S. Karger AG, Basel.