Biopsy of focal liver lesions: guidelines, comparison of techniques and cost-analysis

When a focal liver lesion is discovered, differentiation between a benign and malignant nature and further characterization are mandatory to guide further treatment. Histology remains the golden standard. Improving imaging techniques such as contrast enhanced Doppler ultrasonography, spiral CT and new MRI procedures are promising, but not 100% accurate. When there is any doubt, biopsy should be performed. Fine Needle Aspiration Biopsy (FNAB) has a high sensitivity and specificity (90-95%) in experienced hands, but has a high insufficient sampling rate (up to 15%). In a series of 245 Fine Needle Tru-cut Biopsies (FNTCB) of focal solid liver lesions performed at our institution, sensitivity and specificity for the diagnosis of malignancy were 86% and 100% respectively, with an overall accuracy of 88%. Positive predictive value was 100%, but negative predictive value was rather low (56%). Insufficient sampling rate was low (2.5%), and a more accurate histological characterization was possible compared to FNAB. Finally, the cost-analysis of different biopsy techniques is presented for the Belgian situation according to used materials, pathology procedures and hospitalization.