Rationale and objectives: Pancreatic lesions are frequently detected in pancreatic phase only, which may lead to false negative findings in CT-guided biopsies. We evaluated the accuracy and complication rate of CT guided biopsies of pancreatic lesions with i.v.-contrast application following needle placement in comparison to biopsy after contrast enhanced CT.
Materials and methods: In 30 patients planning and needle placement was performed on the basis of a native planning CT and prior diagnostic CT or MRT. After needle placement contrast enhanced CT was performed to confirm needle course and adjusted if necessary (group 1). In 30 additional patients biopsy was planned based on contrast enhanced CT and needle was placed in the lesion. Control scans confirmed correct needle position (group 2). An 18G coaxial system was used for both groups. Statistical analysis was performed with Student's t and Fisher's exact test for comparison of lesion size, location as well as accuracy and complication rates.
Results: Mean lesion size was significantly smaller in group 1 (31 mm vs. 39 mm; p = 0.02). Diagnostic accuracy and sensitivity for malignancy in group 1 was 93% and 92% versus 80% and 77% in group 2. Complications related to the procedure, i.e. haematoma (n = 5, group 1/n = 2, group 2) and pain (n = 0, group 1/n = 2, group 2) did not statistically differ.
Conclusion: CT-guided biopsy of pancreatic lesions with i.v.-contrast application following needle placement is a reliable method and provides superior accuracy compared to biopsies performed after contrast enhanced planning CT.