Prognostic ability of 18F-FDG PET/CT in the assessment of colorectal liver metastases.
Modern multidisciplinary therapy for colorectal liver metastases (CRLM) is associated with significant morbidity and must be adapted to the patient's relative risk. The tools currently available to risk-stratify patients are limited. This study assessed the prognostic utility of metabolic measurements derived from(18)F-FDG PET compared with previously proposed prognostic scoring systems.


METHODS
Preoperative (18)F-FDG PET/CT studies from a series of 30 patients who underwent liver resection for CRLM after neoadjuvant chemotherapy were evaluated. Quantitative (18)F-FDG PET analysis calculated the maximum and mean standardized uptake value, metabolic tumor volume (MTV), and tumor glycolytic volume (TGV) as measures of the metabolic activity of tumors. The predictive value of these parameters was compared with that of 4 prognostic scores developed by Fong, Iwatsuki, Nordlinger, and Rees.


RESULTS
High MTV and TGV in patients before metastasectomy were significantly associated with poorer overall survival (MTV: P = 0.001; TGV: P = 0.004) and recurrence-free survival (MTV: P = 0.001, TGV; P = 0.002). Maximum and mean standardized uptake value did not show any significant predictive ability. Of the prognostic scores, prediction of outcome was most accurate using the Basingstoke index (area under the curve, 0.898).


CONCLUSIONS
Assessment of metabolic tumor burden with volumetric (18)F-FDG PET parameters appears to be a valuable adjunct in determining the biology of CRLM before surgical resection and may enable better risk stratification of patients.
Department of Surgery, Austin Hospital, University of Melbourne, Victoria, Australia. surgery-armc@unimelb.edu.au
Vijayaragavan
V
Muralidharan
Marco
M
Kwok
Sze Ting
ST
Lee
Lawrence
L
Lau
Andrew M
AM
Scott
Christopher
C
Christophi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001692:Biological Transport; D015179:Colorectal Neoplasms / Q000473:pathology*; D019788:Fluorodeoxyglucose F18; D006019:Glycolysis; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden
D019788:Fluorodeoxyglucose F18