Detection of hepatic metastases from colorectal cancer: prospective evaluation of gray scale US versus SonoVue® low mechanical index real time-enhanced US as compared with multidetector-CT or Gd-BOPTA-MRI.
OBJECTIVE
To compare ultrasound (US), low-mechanical index contrast enhanced US (CEUS) and multidetector-CT (MDCT) for the detection of hepatic metastases from colorectal cancer.


METHODS
From January to June 2006, 110 patients (65 males, 45 females; mean age 62 years; range 39-78) with suspected hepatic lesions from colorectal cancer were prospectively evaluated with US, CEUS and MDCT by two independent readers. Intraoperative ultrasonography (IOUS, n = 45) or a follow-up up for at least 6 months by using MDCT or Gd-BOPTA-enhanced MRI was considered the gold standard. McNemar test was employed.


RESULTS
Reference standards revealed 430 metastases in 110 patients. On a patient-by-patients analysis, CEUS improved US sensitivity from 67.4-71.6% to 93.4-95.8% (p < 0.05). On a lesion-by-lesion analysis, CEUS improved the sensitivity of US from 60.9-64.9% to 85.3-92.8% (p < 0.001). The specificity increased from 50-60% to 76.7-83.3%. No significant differences in sensitivity or specificity between CEUS and MDCT were found. Contrast-enhanced US was significantly more sensitive than baseline US in the detection of metastases smaller than 1 cm (p < 0.001) with an increase in sensitivity from 29.1-35% to 63.3-76.6% no significant statistical difference was identified when compared with MDCT (sensitivity of 73.3-75.8%).


CONCLUSIONS
CEUS is significantly more accurate than US and highly comparable with MDCT in the detection of liver metastases from colorectal cancer. Therefore, in the evaluation of patients with suspected hepatic metastases from colorectal tumour, US examination must be performed after contrast administration.
Cantisani
V
V
Department of Radiology, University La Sapienza, Rome, Italy. vito.cantisani@uniroma1.it
Ricci
P
P
Erturk
M
M
Pagliara
E
E
Drudi
F
F
Calliada
F
F
Mortele
K
K
D'Ambrosio
U
U
Marigliano
C
C
Catalano
C
C
Marin
D
D
Di Seri
M
M
Longo
F
F
Passariello
R
R
D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds; D010743:Phospholipids; D011446:Prospective Studies; D012015:Reference Standards; D012680:Sensitivity and Specificity; D013459:Sulfur Hexafluoride; D036542:Tomography, Spiral Computed / Q000379:methods*; D014463:Ultrasonography / Q000379:methods*
D003287:Contrast Media; D009942:Organometallic Compounds; D010743:Phospholipids; C420843:contrast agent BR1; C064572:gadobenic acid; D008536:Meglumine; D013459:Sulfur Hexafluoride