Safety and efficacy of cytology brushings versus standard FNA in evaluating cystic lesions of the pancreas: a pilot study

Background: Cystic neoplastic lesions of the pancreas (CNLP) are increasingly detected and are associated with a potential for malignant transformation. Diagnostic assessment of these lesions is often limited by the cystic nature and focality of neoplastic progression of these lesions. EUS-guided FNA (EUS-FNA) of cyst fluid and exfoliated cells is one of the most accurate methods of diagnosis but still has limited sensitivity. A new, through-the-needle cytologic brush system has recently been approved for use during EUS evaluation of cystic lesions of the pancreas. Objective: To evaluate the cytologic yield and safety profile of the new cytobrush compared with conventional FNA in evaluating CNLP. Design: Ten consecutive patients with CNLP were included. All cysts were sampled by standard EUS-FNA (0.5 of cyst volume) followed by brush cytology, then by aspiration of the remaining fluid. Fluid samples were separately submitted (standard FNA and cytobrushings FNA) but were read by the same pathologist. Complications were assessed during the immediate postprocedure period (2-3 hours) and by a telephone call conducted approximately 30 days after the procedure to inquire about any new symptoms, including abdominal pain, melena, hematochezia, hematemesis, fever, nausea, and vomiting. Setting: High-volume EUS referral center. Patients: Ten consecutive patients with CNLP that measured at least 20 mm in maximal dimension were included. Main Outcome Measurements: Cellularity and presence of diagnostic cells on the FNA. Results: In 7 of 10 cases, the EchoBrush specimen was superior to FNA in terms of cellularity and detection of diagnostic cells. Two cases had complications: 1 major and 1 minor intracystic bleed. No infection or pancreatitis was observed. Limitations: The interpreting pathologist for the case was not blinded to the results of either of the samples. In addition, this pilot study represents only a single-center experience. Conclusions: This study suggests that brush cytology specimens obtained at the time of EUS are superior to conventional FNA because of the higher yield of epithelial cells. It is unclear whether bleeding is more common after EchoBrush sampling; however, caution should be taken in patients who require anticoagulation until further data are available.