Biopsy of resectable colorectal liver metastases causes tumour dissemination and adversely affects survival after liver resection

Background: Liver resection is increasingly being performed for metastatic colorectal cancer. This study assessed the need for preoperative biopsy of suspected metastases and whether biopsy has any effect on long-term survival. Methods: Prospectively collected data on patients who underwent liver resection for colorectal metastases between 1986 and 2003 were reviewed retrospectively. The endpoints of morbidity, operative mortality and long-term survival were compared between patients who had biopsy before referral (group 1) and those who did not (group 2). Results: Patient demographics and disease distribution were similar for 90 patients in group 1 and 508 in group 2. Seventeen patients (19 per cent) who had undergone biopsy either at the time of colorectal resection or radiologically had evidence of needle-track deposits. Operative mortality and morbidity rates in the two groups were similar. The 4-year survival rate after liver resection was 32.5 (s.e. 5.5) per cent in group 1, compared with 46.7 (2.8) per cent in group 2 (P = 0.008). Conclusion: Needle-track deposits are common after biopsy of suspected colorectal liver metastases. Biopsy of metastases confers poorer long-term survival on patients after liver resection and cannot be justified in patients with potentially resectable disease.