Accuracy and safety of percutaneous US-guided needle biopsies in liver metastasis and hemangiomas

The aim of this study was to compare small size aspiration and large size cutting needles on the diagnostic yield in the biopsies of liver and especially to investigate the reliability on percutaneous biopsy of liver hemangiomas.

Nine hundred fifty patients with percutaneous ultrasonography-guided liver biopsies were evaluated retrospectively. This study enrolled 841 patients biopsied with either large size cutting needle (Tru-cut 14G-18G) or small size aspiration needle (WestCott 20G). Further evaluation was performed in 312 patients with metastasis and 48 patients with hemangiomas.

Diagnostic yield was higher in the large size cutting needle group (96.8%, 150/155) than in the small size aspiration needle group (84.1%, 132/157) in liver metastasis (P<0.001). There was no significant difference among diagnostic accuracies of Tru-cut 14G, 16G, and 18 G needles in metastasis (P=0.255). Accuracy rate was 77.9% (208/267) in benign and 89.5% (514/574) in malignant diseases. Sensitivity, specificity, and accuracy were 81.2% (514/633), 100% (208/208), and 85.8% (722/841), respectively. Only two major complications were found (0.16%) with small needles.

The authors suggest the use of large size cutting needles, because they provide more accurate diagnosis, and should be used in liver metastasis instead of small aspiration needles, if there is no on-site pathologist at aspiration biopsies or a more specific diagnosis is required. Among them, 18G cutting needle should be chosen. All the needles, including the large cutting type, were found safe in the biopsies of liver hemangiomas.