Staging of colorectal liver metastases after preoperative chemotherapy. Diffusion-weighted imaging in combination with Gd-EOB-DTPA MRI sequences increases sensitivity and diagnostic accuracy

Abstract

Objectives To compare the diagnostic accuracy and sensitivity of Gd-EOB-DTPA MRI and diffusion-weighted (DWI) imaging alone and in combination for detecting colorectal liver metastases in patients who had undergone preoperative chemotherapy. Methods Thirty-two consecutive patients with a total of 166 liver lesions were retrospectively enrolled. Of the lesions, 144 (86.8 %) were metastatic at pathology. Three image sets (1, Gd-EOB-DTPA; 2, DWI; 3, combined Gd-EOB-DTPA and DWI) were independently reviewed by two observers. Statistical analysis was performed on a per-lesion basis. Results Evaluation of image set 1 correctly identified 127/ 166 lesions (accuracy 76.5 %; 95 % CI 69.3-82.7) and 106/ 144 metastases (sensitivity 73.6 %, 95 % CI 65.6-80.6). Evaluation of image set 2 correctly identified 108/166 (accuracy 65.1 %, 95 % CI 57.3-72.3) and 87/144 metastases (sensitivity of 60.4 %, 95 % CI 51.9-68.5). Evaluation of image set 3 correctly identified 148/166 (accuracy 89.2 %, 95 % CI 83.4-93.4) and 131/144 metastases (sensitivity 91 %, 95 % CI 85.1-95.1). Differences were statistically significant (P<0.001). Notably, similar results were obtained analysing only small lesions (<1 cm). Conclusions The combination of DWI with Gd-EOB-DTPAenhanced MRI imaging significantly increases the diagnostic accuracy and sensitivity in patients with colorectal liver metastases treated with preoperative chemotherapy, and it is particularly effective in the detection of small lesions. Key Points • Accurate detection of colorectal liver metastases is essential to determine resectability.• Almost 80 % of patients are candidates for neoadjuvant chemotherapic treatment at diagnosis. After chemotherapy, metastases usually decrease, and drug-induced liver steatosis may be present.• The sensitivity of imaging is significantly inferior to that in chemotherapy-naïve patients.• DWI combined with Gd-EOB-DTPA increases sensitivity in detecting small metastases after chemotherapy.

The target sign in colorectal liver metastases: an atypical Gd-EOB-DTPA “uptake” on the hepatobiliary phase of MR imaging

“…Macera et al observed that assessment of DWI findings is particularly important to identify small lesions, which may be missed or misinterpreted as peripheral vasculo-biliary structures or artifacts in contrast-enhanced sequences [9]. Also the use of the liverspecific MRI contrast agent Gd-EOB-DTPA in combination with DWI has increased the detection rate [9]. In our series, all the lesions were visible and all showed a diffusion restriction.…”

“…A previous study showed that the inner area of marked hyperintensity corresponds to cystic change or necrosis [8]. Macera et al observed that assessment of DWI findings is particularly important to identify small lesions, which may be missed or misinterpreted as peripheral vasculo-biliary structures or artifacts in contrast-enhanced sequences [9]. Also the use of the liverspecific MRI contrast agent Gd-EOB-DTPA in combination with DWI has increased the detection rate [9].…”

Gadoxetic acid-enhanced MRI and diffusion-weighted imaging for the detection of colorectal liver metastases after neoadjuvant chemotherapy

“…According a recent meta-analysis study [15], a pooled sensitivity of 85.7 % for MR was reported for the detection of CRLM in the neoadjuvant setting. In a more recent study, Macera et al [23] reported the diagnostic accuracy of 89.2 % and sensitivity of 91 % for the combination of DWI with gadoxetic acid-enhanced MRI in patients with CRLM treated with preoperative chemotherapy. Our study results agree well with those of the above studies.…”

“…Recently, gadoxetic acid (Gd-EOB-DTPA, Primovist®; Bayer Healthcare, Berlin, Germany), which is a hepatocyte-specific MR contrast agent, has received much attention as a promising contrast medium for the evaluation of liver metastases [16][17][18]. In addition, several studies have demonstrated that the combination of DWI and gadoxetic acid-enhanced MRI can improve the accuracy and sensitivity for the detection of liver metastasis, especially for small liver metastasis, as well as after preoperative chemotherapy [19][20][21][22][23]. However, to the best of our knowledge, there have been no large series studies regarding this issue or data on the diagnostic performance of MRI with gadoxetic acid for the detection of CRLM in patients with NAC.…”

Focal liver lesions detection and characterization: The advantages of gadoxetic acid-enhanced liver MRI

“…Considering the detection of small metastases, Shimada et al [60] reported higher diagnostic accuracy of Gd-EOB-DTPA in comparison to DWI. Probably, both imaging modalities represent very important diagnostic tools in the evaluation of FLLs, as recently described in a study by Macera et al [61] . They found that the combination of DWI with Gd-EOB-DTPA-enhanced MRI imaging significantly increases the diagnostic accuracy sensitivity in patients with colorectal liver metastases treated with preoperative chemotherapy [61] .…”