[Incidence and significance of small focal liver lesions in MRI].
OBJECTIVE
Analysis of the frequency and significance of small focal liver lesions (< or = 2 cm) detected on MRI in the presence or absence of a history of malignancy.


METHODS
628 MRI examinations of the liver performed during 1994-1996 were evaluated. The inclusion criterion into the study was the detection of a focal liver lesion with a size < or = 2 cm. The frequency, the size, the diagnostic proof, and the differential diagnosis of the focal liver lesions were analysed with regard to the patients history of a known malignant tumor.


RESULTS
Overall, 179 of the 628 patients (28.5%) had focal liver lesions < or = 2 cm (n = 338). 58.9% of the lesions could be classified based upon follow-up studies by ultrasound, CT or MRI, or by biopsy. The remaining 41.1% of the lesions could not be classified due to the absence of follow-up examinations. 57.3% of all proven lesions were benign and 42.7% were malignant. A history of a malignant tumor was present in 76.7% of all patients with small liver lesions; however, lesions were benign in these patients in 50.6% of the cases. In patients with no known history of a malignancy, 75% of the lesions were benign and 25% were malignant. However, these malignant lesions were in 10/11 cases hepatocellular carcinomas in patients with liver cirrhosis.


CONCLUSIONS
Even in the presence of a history of a malignant tumor, about 50% of the detected small liver lesions on MRI are benign. In the absence of a tumor history the probability of a small malignant liver lesion is very low, if the patients does not have liver cirrhosis where small hepatocellular carcinomas can be present.
Kreft
B
B
Radiologische Klinik der Universität Bonn. Kreft@mailer.meb.uni-bonn.de
Pauleit
D
D
Bachmann
R
R
Conrad
R
R
Krämer
A
A
Schild
H H
HH
D001706:Biopsy; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000175:diagnosis / Q000473:pathology; D008107:Liver Diseases / Q000175:diagnosis* / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000556:secondary; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged