Tumor implantation from needle biopsy of hepatic metastases.

Two patients with resectable secondaries in the liver developed needle track recurrence following intraoperative "Trucut"-needle biopsy and percutaneous thin needle aspiration cytology, respectively. In both cases the nature of the hepatic lesion was already clear before biopsy, from characteristic ultrasound, CT-scan, and a progressive rise in CEA levels. Although the overall risk is presumably low, biopsy must not become a diagnostic imperative. It may compromise definitive surgery in individual patients, and should therefore be restricted to situations in which results have a therapeutic or scientific impact.