[Types of liver metastases on MR imaging and characteristics of uncommon types].
OBJECTIVE
Although liver metastases are very common, some of them would be misdiagnosed because of their specific appearance on imaging. This study was to summarize the types of liver metastases according to the magnetic resonance imaging (MRI) appearance, and explore the characteristics of uncommon types to improve the accuracy of diagnosis.


METHODS
A total of 174 consecutive patients with liver metastases were screened from the patients with diagnosis or suspicion of liver metastases according to plate or enhanced MRI scan. Liver metastases were confirmed through pathologic examination, medical imaging, or follow-up. Lesions were categorized as nodular, segment, and diffusion classes by shape, and categorized as common, mimicking hemangioma, and mimicking cyst patterns according to the characteristics of signal intensity.


RESULTS
Common primary tumors of liver metastases were colon and rectum carcinomas (31.0%). According to the shape of lesions, the proportions of nodular, segment, and diffusion classes were 96.6%, 2.3%, and 1.1%, respectively. According to the characteristics of signal intensity, the proportions of common, mimicking hemangioma, and mimicking cyst patterns were 87.9%, 4.0%, and 8.1%, respectively.


CONCLUSIONS
Most liver metastases are nodular in shape, and present as common pattern, but some uncommon types also exist. MRI scan and clinical follow-up could increase the accuracy of diagnosis.
Department of Radiology, The Second Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510120, P. R. China. aliyong@126.com
Yong
Y
Li
Rong
R
Zhang
Bi-Ling
BL
Liang
Jian-Peng
JP
Yuan
Rui-Xin
RX
Ye
Jing-Lian
JL
Zhong
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000556:secondary*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000473:pathology; D012004:Rectal Neoplasms / Q000473:pathology