Assessment of the residual tumour of colorectal liver metastases after chemotherapy: diffusion-weighted MR magnetic resonance imaging in the peripheral and entire tumour.
OBJECTIVE
To evaluate the value of diffusion-weighted imaging (DWI) in detecting residual tumours (RTs) in colorectal liver metastases (CLMs) following chemotherapy, with a focus on tumour periphery.


METHODS
From January 2009-January 2012, 57 patients who underwent liver resection for CLMs with preoperative MRI (<3 months) including DWI were retrospectively included. CLMs were classified into three response groups on pathology: (1) major histological (MHR, RTs ≤ 10 %), (2) partial histological (PHR, RT = 10-49 %), and (3) no histological (NHR, RT ≥ 50 %). On DWI, regions of interest (ROIs) were drawn around the entire tumour and tumour periphery. Apparent diffusion (ADC) and pure diffusion (D) coefficients were calculated using a monoexponential fit, and compared using Kruskal-Wallis test on a lesion-per-lesion analysis.


RESULTS
111 CLMs were included. Fourteen (12.5 %), 42 (38 %) and 55 (49.5 %) CLMs presented a MHR, PHR and NHR, respectively. ADC and D of the peripheral ROIs were significantly higher in the MHR group (P = 0.013/P = 0.013). ADC and D from the entire tumour were not significantly different among the groups (P = 0.220/P = 0.103).


CONCLUSIONS
In CLM treated with chemotherapy, ADC and D values from the entire tumour are not related to the degree of RT, while peripheral zone diffusion parameters could help identify metastases with MHR.


CONCLUSIONS
Peripheral ADC and D of CLMs were higher with major pathological responses. Global ADC and D of CLMs were not different according to residual tumour. Diffusion-weighted images of CLM periphery could be an interesting biomarker of MHR. Diffusion-weighted images could be used to help tailor treatment.
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France. wagner.mathilde@gmail.com.
Mathilde
M
Wagner
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France.|Radiology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hôpitaux de Paris, APHP, Clichy, France.
Maxime
M
Ronot
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France.
Sabrina
S
Doblas
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France.
Céline
C
Giraudeau
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France.|Radiology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hôpitaux de Paris, APHP, Clichy, France.
Bernard
B
Van Beers
Hepatobiliary Surgery Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hôpitaux de Paris, APHP, Clichy, France.
Jacques
J
Belghiti
Pathology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hôpitaux de Paris, APHP, Clichy, France.
Valérie
V
Paradis
INSERM, UMR 1149, Paris Diderot University, 100, Bd du Général Leclerc, 92110, Clichy, France.|Radiology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hôpitaux de Paris, APHP, Clichy, France.
Valérie
V
Vilgrain
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D012189:Retrospective Studies
D000970:Antineoplastic Agents
Colorectal cancer; Diffusion weighted-imaging; Lesion periphery; Liver metastases; Residual tumours