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CT-guided transvenous or transcaval needle biopsy of pancreatic and peripancreatic lesions.

PURPOSE
To evaluate the safety and efficacy of direct computed tomography (CT)-guided fine needle aspiration biopsy (FNAB) of pancreatic and peripancreatic masses via a posterior approach that traverses the inferior vena cava (IVC) or renal vein.


MATERIALS AND METHODS
From January 2000 to July 2003, 55 patients underwent 58 biopsies of masses located within the pancreas (n = 28) or in a peripancreatic location (n = 30) with use of a posterior approach that crossed the IVC or renal vein. Biopsies were performed with needles ranging in size from 18 to 22. Cytology reports and medical records of all patients were retrospectively reviewed to evaluate diagnostic accuracy and complication rates.


RESULTS
Masses were safely accessed with a direct (noncoaxial) pathway traversing the IVC (n = 54), renal vein (n = 4), or both (n = 3). Overall diagnostic accuracy was 86% (50 of 58). Cytologic examination was positive for malignancy in 39 of 58 biopsies (67%). Benign lesions were demonstrated in 12 of 58 biopsies. In seven cases (12%), the sample was deemed nondiagnostic. Of those, four were diagnosed later by endoscopy (n = 1), surgical biopsy (n = 2), or repeat FNAB (n = 1). A false-negative result was noted in one case, which was later diagnosed by repeat biopsy. A total of four inadvertent passes through the right renal artery were recorded. CT evidence of perilesional blood was seen in eight of 55 patients (eight of 58 cases). Three of these occurred after a passage via the right renal artery. All patients remained asymptomatic, and no transfusion or change in management was necessary. No other complications occurred.


CONCLUSION
CT-guided noncoaxial FNAB with an approach that traverses the IVC or renal vein is safe and effective in obtaining diagnostic specimens from pancreatic and peripancreatic masses.