Computed tomography-guided percutaneous biopsy of isoattenuating focal liver lesions

The purpose of this study was to evaluate the efficacy of CT-guided percutaneous biopsy of isoattenuating liver lesions using anatomic landmarks (ALs) to guide needle placement and added value of intravenous (IV) contrast.

An interventional radiology database was reviewed to identify patients with CT-guided percutaneous biopsy of isoattenuating focal liver lesions using ALs to guide needle placement. The cohort was further divided into two groups: lesions biopsied using ALs only and lesions biopsied using ALs and intravenous contrast (AL+IV). Pathology results or follow-up imaging served as reference standard. Sensitivity and accuracy were calculated, Student's t test and Fisher's exact test were used for statistical comparison between the two groups.

Between January 2000 and December 2011, CT-guided percutaneous biopsy of 133 isoattenuating focal liver lesions was performed in 133 patients. The AL group included 54 patients (M:F = 29:25) with 54 lesions (size range 7-90 mm, mean 32.1 ± 18.1) and AL+IV group included 79 patients (M:F = 44:35) with 79 lesions (size range 7-100 mm, mean 25.6 ± 15.0). AL group included 23 (43%) benign and 31 (57%) malignant lesions; AL+IV group included 31 (39%) benign and 48 (61%) malignant lesions. Sensitivity and accuracy for CT-guided biopsy of focal isoattenuating liver lesions were, overall 94% and 96%, AL group 97% and 98% and AL+IV group 92% and 94%, with no statistical significant difference between the AL and AL+IV groups (P = 0.88-1.00).

Accurate planning and utilizing of internal reference ALs is successful in yielding a diagnostic sample for CT-guided percutaneous biopsy of isoattenuating focal liver lesion. The confidence of accurate targeting can be enhanced by administering IV contrast, however, since the visualization provided by IV contrast can be short-lived; use of IV contrast does not obviate the need for precise planning based on ALs.