Impact of preoperative positron emission tomography scans on survival after liver resection for metastatic colorectal cancer

Abstract

Aim: Positron emission tomography (PET) has been used to detect extrahepatic disease in patients in order to determine their suitability for liver resection from colorectal metastases. Our hypothesis is that PET scanning would result in a better 5-year survival after liver resection due to better patient selection through downstaging of disease. Methods: Between 1997 and 2005 there were 467 patients undergoing potentially curative liver resections in three cohorts. PET scanning was available to our patients without restriction from 2002. There were 215 patients in the pre-PET era (Group 1), 188 in the PET era where a PET scan was not performed (Group 2) and 64 patients with preoperative PET scanning (Group 3). Our three cohorts were followed up at 1, 3, 6 and 12months postoperatively with a median follow up of 24, 21 and 20months, respectively. Results: The 5-year survival rate for patients with preoperative PET scanning was 68%. The 5-year survival rate for patients without preoperative PET scanning was 40% in the PET era and 30% in the pre-PET era (P = 0.0113). The disease-free interval was 35% in the PET group and 20% without PET scans at 3years (P < 0.05). Conclusion: The usage of preoperative PET scanning has led to an improved overall survival because of better patient selection from detection of occult extrahepatic disease missed by traditional staging techniques. © 2008 The Author Journal compilation © 2008 College of Surgeons of Hong Kong.