Percutaneous Radiofrequency Ablation of Colorectal Cancer Liver Metastases: Factors Affecting Outcomes--A 10-year Experience at a Single Center.
OBJECTIVE
To identify predictors of oncologic outcomes after percutaneous radiofrequency ablation (RFA) of colorectal cancer liver metastases (CLMs) and to describe and evaluate a modified clinical risk score (CRS) adapted for ablation as a patient stratification and prognostic tool.


METHODS
This study consisted of a HIPAA-compliant institutional review board-approved retrospective review of data in 162 patients with 233 CLMs treated with percutaneous RFA between December 2002 and December 2012. Contrast material-enhanced CT was used to assess technique effectiveness 4-8 weeks after RFA. Patients were followed up with contrast-enhanced CT every 2-4 months. Overall survival (OS) and local tumor progression-free survival (LTPFS) were calculated from the time of RFA by using the Kaplan-Meier method. Log-rank tests and Cox regression models were used for univariate and multivariate analysis to identify predictors of outcomes.


RESULTS
Technique effectiveness was 94% (218 of 233). Median LTPFS was 26 months. At univariate analysis, predictors of shorter LTPFS were tumor size greater than 3 cm (P < .001), ablation margin size of 5 mm or less (P < .001), high modified CRS (P = .009), male sex (P = .03), and no history of prior hepatectomy (P = .04) or hepatic arterial infusion chemotherapy (P = .01). At multivariate analysis, only tumor size greater than 3 cm (P = .01) and margin size of 5 mm or less (P < .001) were independent predictors of shorter LTPFS. Median and 5-year OS were 36 months and 31%. At univariate analysis, predictors of shorter OS were tumor size larger than 3 cm (P = .005), carcinoembryonic antigen level greater than 30 ng/mL (P = .003), high modified CRS (P = .02), and extrahepatic disease (EHD) (P < .001). At multivariate analysis, tumor size greater than 3 cm (P = .006) and more than one site of EHD (P < .001) were independent predictors of shorter OS.


CONCLUSIONS
Tumor size of less than 3 cm and ablation margins greater than 5 mm are essential for satisfactory local tumor control. Tumor size of more than 3 cm and the presence of more than one site of EHD are associated with shorter OS.
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Waleed
W
Shady
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Elena N
EN
Petre
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Mithat
M
Gonen
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Joseph P
JP
Erinjeri
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Karen T
KT
Brown
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Anne M
AM
Covey
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
William
W
Alago
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Jeremy C
JC
Durack
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Majid
M
Maybody
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Lynn A
LA
Brody
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Robert H
RH
Siegelbaum
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Michael I
MI
D'Angelica
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
William R
WR
Jarnagin
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Stephen B
SB
Solomon
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Nancy E
NE
Kemeny
From the Section of Interventional Radiology, Department of Radiology (W.S., E.N.P., J.P.E., K.T.B., A.M.C., W.A., J.C.D., M.M., L.A.B., R.H.S., S.B.S., C.T.S.), Department of Epidemiology and Biostatistics (M.G.), Department of Surgery (M.I.D., W.R.J.), and Department of Medicine (N.E.K.), Memorial Sloan-Kettering Cancer Center, 1275 York Ave, Room H-118, New York, NY 10065.
Constantinos T
CT
Sofocleous
D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D006498:Hepatectomy / Q000379:methods; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary* / Q000601:surgery*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008297:Male; D011379:Prognosis; D015641:Radiography, Interventional / Q000379:methods*; D012189:Retrospective Studies; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D003287:Contrast Media