Diagnosis of pancreatic cysts: EUS-guided, through-the-needle confocal laser-induced endomicroscopy and cystoscopy trial: DETECT study

Background: The diagnosis of pancreatic cystic neoplasms (PCNs), which now depends on morphology, cytology, and fluid analysis, is still challenging. A novel confocal laser endomicroscopy probe that can be inserted through a 19-gauge FNA needle allows needle-based confocal laser endomicroscopy (nCLE), and the feasibility of nCLE has been reported in PCNs. The combination of cystoscopy by using a through-the-needle fiberoptic probe in combination with nCLE under EUS guidance may improve the diagnosis of PCNs. Objective: To assess the feasibility, safety, and diagnostic yield of the combination of cystoscopy and nCLE in the clinical diagnosis of PCNs. Design: A prospective feasibility study. Setting: An academic tertiary referral center. Patients: Thirty patients with PCNs. Interventions: EUS-guided dual through-the-needle imaging (cystoscopy and nCLE) for PCNs. Main Outcome Measurements: Technical feasibility and safety. Associations of cystoscopy and nCLE findings with clinical diagnosis of PCNs. Results: The procedure was technically successful with the exception of 1 probe exchange failure. In 2 patients (7%), postprocedure pancreatitis developed. Specific features associated with the clinical diagnosis of mucinous cysts were identified: mucin on cystoscopy and papillary projections and dark rings on nCLE. The sensitivity of cystoscopy was 90% (9/10), and that of nCLE was 80% (8/10), and the combination was 100% (10/10) in 18 high-certainty patients. Limitations: A single-center study and lack of complete pathologic correlation. Conclusion: The combination of dual through-the-needle imaging (cystoscopy and nCLE) of pancreatic cysts appears to have strong concordance with the clinical diagnosis of PCN.