Published online Mar 14, 2015. doi: 10.3748/wjg.v21.i10.3049
Peer-review started: June 3, 2014
First decision: July 21, 2014
Revised: August 29, 2014
Accepted: September 29, 2014
Article in press: September 30, 2014
Published online: March 14, 2015
Processing time: 286 Days and 21 Hours
AIM: To evaluate the prognostic value of pretreatment FDG positron emission tomography computed tomography (PET-CT) in patients with hepatocarcinoma treated by liver transplantation (LT).
METHODS: The authors retrospectively analyzed the data of 27 patients (mean age 58 ± 9 years) who underwent FDG PET-CT before LT for hepatocarcinoma. Mean follow-up was 26 ± 18 mo. The FDG PET/CT was performed according to a standard clinical protocol: 4 MBqFDG/kg body weight, uptake 60 min, low-dose non-enhanced CT. The authors measured the SUVmax and SUVmean of the tumor and the normal liver. The tumor/liver activity ratios (RSUVmax and RSUVmean) were tested as prognostic factors and compared to the following conventional prognostic factors: MILAN, CLIP, OKUDA, TNM stage, alphafoetoprotein level, portal thrombosis, size of the largest nodule, tumor differentiation, microvascular invasion, underlying cirrhosis and liver function.
RESULTS: Overall and recurrence free survivals were 80.7% and 67.4% at 3 years, and 70.6% and 67.4% at 5 years, respectively. According to a multivariate Cox model, only FDG PET/CT RSUVmax predicted recurrence free survival. Even though the MILAN criteria alone were not predictive, it is worth noting that none of the patients outside the MILAN criteria and with RSUVmax < 1.15 relapsed.
CONCLUSION: FDG PET/CT with an RSUVmax cut-off value of 1.15 is a strong prognostic factor for recurrence and death in patients with HCC treated by LT in this retrospective series. Further prospective studies should test whether this metabolic index should be systematically included in the preoperative assessment.
Core tip: Patients suffering from hepatocarcinoma are selected for liver transplantation (LT) according to the Milan criteria that were established two decades ago. The aggressiveness of the tumor has also a particular importance, but there is still no ideal way of predicting the risk of recurrence according to pretransplant tumor metabolism. This study confirms that FDG positron emission tomography computed tomography with a tumor/liver activity ratios (RSUVmax) cut-off value of 1.15 is a strong prognostic factor for recurrence and death in patients with hepatocellular cancer (HCC) treated by LT. In addition, in this series, none of the patients outside the MILAN criteria with RSUVmax < 1.15 suffered from recurrence in the follow-up. Further prospective studies should test whether this metabolic index should be systematically included in the pretransplant assessment of HCC patients.