Purpose: Precision oncology relies on frequent pathologic, molecular, and genomic assessments of tumor tissue to guide treatment selection, evaluate pharmacodynamic effects of novel agents, and determine drug resistance mechanisms. Newer forms of analyses such as drug screens in cell lines and patient-derived xenografts demand increasing amounts of tissue material. It remains unknown how the need for serial biopsies with large numbers of tumor cores relates to tissue yields and biopsy complication rates.
Materials and methods: In this study, we performed a retrospective analysis of 199 focal liver biopsies performed in 143 patients in the setting of oncologic research protocols (research biopsy group) over a 4-year period at a single-intervention oncology service. Practice patterns and complication rates were compared with those related to 1,522 consecutive biopsies performed in 1,154 patients in whom two cores were obtained for standard clinical management of patients (standard biopsy).
Results: In the research biopsy group, 1,100 tissue cores (average, 5.5 cores per procedure) were harvested and distributed to trial sponsors, internal research laboratories, and pathology services. The complication rate in this cohort was 0.5% for major complications (one of 199) and 1.0% for minor complications managed conservatively (two of 199). In the standard biopsy control group, major complications were observed in 1.4% of procedures (22 of 1,522) and minor complications in 0.2% (three of 1,522). These complication rates were not statistically different.
Conclusion: Harvesting extra tissue cores through coaxial needles during focal liver biopsies does not increase complication rates and yields valuable tissue for additional experimental testing.