CT-Guidance Useful as Alternative Pancreatic Biopsy Method

A new study shows that when endoscopic ultrasound (EUS)-guided biopsy of pancreatic masses is problematic, computed tomography (CT)-guided biopsy can be used as an alternative method.

Researchers at Taipei Medical University (Taiwan) and National Yang-Ming University (Taipei, Taiwan) reviewed 34 CT-guided biopsies in patients with pancreatic mass to assess the safety, yield, and clinical utility of percutaneous transgastric CT-guided biopsy of pancreatic tumor using large needles. All of the patients in the study were unwilling or failed to undergo EUS-guided biopsy. Of these, 24 (71%) had a direct path to the mass without passing through a major organ. The remaining nine transgastric biopsies, which were the basis for the study, used a coaxial technique, involving a 7-gauge coaxial introducer needle and an 18-gauge biopsy needle. Immediate and late follow-up CT images to detect complications were obtained.

The results showed that tumor tissues were obtained in nine pancreatic biopsies, and histologic specimens for diagnosis were obtained in all cases. One patient, who had a rare sarcomatoid carcinoma, received a second biopsy. An immediate imaging study and clinical follow-up detected neither hemorrhage nor peritonitis, and no delayed procedure-related complication was seen during the survival period of the patients. The study was published in the December 21, 2009, issue of the World Journal of Gastroenterology.

"Eight patients received nine CT-guided transgastric biopsies of pancreatic masses located at the pancreas head or body without passing through vital organs; all procedures went smoothly,” concluded lead author Hsiuo-Shan Tseng, M.D., of the department of radiology at National Yang-Ming University, and colleagues. "Only one patient had transient pneumoperitoneum which completely resolved the next day. Although this is a small series, their study shows that it is feasible to perform transgastric biopsy of a pancreatic lesion using a large needle.”

The diagnosis of a pancreatic mass detected by abdominal imaging can be difficult, and cannot reliably be used to diagnose malignant or benign conditions which may have different treatment options and prognoses; therefore, tissue diagnosis is often needed before surgery. CT-guided biopsy for tissue diagnosis is well established, and fine needle biopsy for pancreatic lesions, according to several studies, has an accuracy rate of 85%, whereas a large needle biopsy has an increased accuracy rate of 92%.

Related Links:
Taipei Medical University
National Yang-Ming University