Prognostic value of pretreatment diffusion-weighted magnetic resonance imaging for outcome prediction of colorectal cancer liver metastases undergoing 90Y-microsphere radioembolization.
OBJECTIVE
To investigate the clinical potential of pretreatment apparent diffusion coefficient (ADC) on diffusion-weighted magnetic resonance imaging (DWI) for therapy response and outcome prediction in patients with liver-predominant metastatic colorectal cancer (CRC) undergoing radioembolization with90Yttrium-microspheres (90Y-RE).


METHODS
Forty-six consecutive patients with unresectable CRC liver metastases underwent standardized clinical DWI on a 1.5 T MR scanner prior to and 4-6 weeks after 90Y-RE. Pretreatment clinical parameters, ADC values derived from region-of-interest analysis, and the corresponding tumor sizes of three treated liver metastases per subject were recorded. Long-term tumor response to radioembolization was categorized into response (partial remission) and nonresponse (stable disease, progressive disease) according to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST) 3 months after treatment. Associations between long-term tumor response and the clinical and imaging parameters were evaluated. The impact of pretreatment clinical and imaging parameters on progression-free survival (PFS) and overall survival (OS) was further assessed by Kaplan-Meier and multivariate Cox-regression analyses.


RESULTS
Nonresponders had higher hepatic tumor burden (p = 0.021) and lower ADC values than patients responding to 90Y-RE, both pretreatment (986 ± 215 vs. 1162 ± 178; p = 0.036) and posttreatment (1180 ± 350 vs. 1598 ± 225; p = 0.002). ADC values higher than 935 × 10-6mm2(5 vs. 3 months; p = 0.022) and hepatic tumor burden ≤25% (6 vs. 3 months; p = 0.014) were associated with longer median PFS, whereas ADC >935 × 10-6mm2(14 vs. 6 months; p = 0.02), hepatic tumor burden ≤25% (14 vs. 6 months; p = 0.048), size of the largest metastasis <4.7 cm (18 vs. 7 months; p = 0.024), and Eastern Cooperative Oncology Group (ECOG) score <1 (8 vs. 5 months; p = 0.045) were associated with longer median OS. On multivariate analysis, ADC >935 × 10-6mm2and hepatic tumor burden ≤25% remained prognostic factors for PFS, and ADC >935 × 10-6mm2and size of the largest metastasis <4.7 cm were independent predictors of OS.


CONCLUSIONS
Pretreatment ADC on DWI represents a valuable prognostic biomarker for predicting both the therapeutic efficacy and survival prognosis in CRC liver metastases treated by 90Y-RE, allowing risk stratification and potentially optimizing further treatment strategies.
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany. Carsten.Schmeel@ukb.uni-bonn.de.
Frederic Carsten
FC
Schmeel
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Birgit
B
Simon
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Julian Alexander
JA
Luetkens
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Frank
F
Träber
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Carsten
C
Meyer
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Leonard Christopher
LC
Schmeel
Department of Nuclear Medicine, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.|Department of Nuclear Medicine, University Hospital Saarland, Universität des Saarlandes, Homburg, Germany.
Amir
A
Sabet
Department of Nuclear Medicine, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.|Department of Nuclear Medicine, University Hospital Saarland, Universität des Saarlandes, Homburg, Germany.
Samer
S
Ezziddin
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Hans Heinz
HH
Schild
Department of Radiology and Radiation Oncology, University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universität Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
Dariusch Reza
DR
Hadizadeh
D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D038524:Diffusion Magnetic Resonance Imaging; D018572:Disease-Free Survival; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D047368:Tumor Burden; D015021:Yttrium Radioisotopes / Q000627:therapeutic use
D015021:Yttrium Radioisotopes
Apparent diffusion coefficient; Colorectal cancer; Diffusion-weighted imaging; Interventional oncology; MRI; Radioembolization