The prognostic value of [F]FDG PET/CT texture analysis prior to transplantation for unresectable colorectal liver metastases.

INTRODUCTION

To determine whether heterogeneity in colorectal liver metastases (CRLM) F fluorodeoxyglucose [F]FDG distribution is predictive of disease-free survival (DFS) and overall survival (OS) following liver transplantation (LT) for unresectable CRLM.

METHODS

The preoperative [F]FDG positron emission tomography/computed tomography examinations of all patients in the secondary cancer 1 and 2 studies were retrospectively assessed. Maximum standardized uptake value (SUV), metabolic tumour volume (MTV), and six texture heterogeneity parameters (joint entropy dissimilarity grey level variance size zone variance and zone percentage, and morphological feature convex deficiency) were obtained. DFS and OS for patients over and under the median value for each of these parameters were compared by using the Kaplan Meier method and log rank test.

RESULTS

Twenty-eight out of 40 patients who underwent LT for unresectable CRLM had liver metastases with uptake above liver background and were eligible for inclusion. Low MTV (p < 0.001) and dissimilarity (p = 0.016) were correlated to longer DFS. Low MTV (p < 0.001) and low values of the texture parameters dissimilarity (p = 0.038), joint entropy (p = 0.015) and zone percentage (p = 0.037) were significantly correlated to longer OS. SUV was not correlated to DFS and OS.

CONCLUSION

Although some texture parameters were able to significantly predict DFS and OS, MTV seems to be superior to predict both DFS and OS following LT for unresectable CRLM.