Probe-based confocal laser endomicroscopy for the diagnosis of pancreatic ductal structures

Background and Aim: The image-based diagnosis of pancreatic diseases can be difficult and requires pathological evaluation. Probe-based confocal laser endomicroscopy (pCLE) enables real-time observation of the microscopic tissue pattern of lesion and may be a useful assistance for the diagnosis. This study aimed to evaluate the feasibility and utility of pCLE for the diagnosis of pancreatic diseases. Methods: Thirty patients who underwent endoscopic retrograde cholangiopancreatography with pCLE for the evaluation of indeterminate pancreatic diseases from June 2015 to October 2018 were included in this study. The pCLE findings were interpreted according to the Miami Classification. Results: Among a total of 30 patients, 12, 10, 4, and 4 patients received the definitive diagnoses of pancreatic ductal adenocarcinoma (PDAC), main duct intrapapillary mucinous neoplasm, autoimmune pancreatitis, and chronic pancreatitis, respectively. The diagnostic accuracy of pCLE for PDAC and pancreatitis (96.7% and 93.3%, respectively) was higher than that of cytology (76.7% and 63.3%, respectively) (P = 0.0227 and 0.0048, respectively). The sensitivity of pCLE for PDAC was significantly higher (91.7%) than that of cytology (41.7%) (P = 0.0094). Moreover, the specificity of pCLE for pancreatitis was significantly higher than that of cytology (90.9% vs 50%; P = 0.0029). However, the diagnostic accuracies of pCLE and cytology for main duct intrapapillary mucinous neoplasm did not differ significantly (96.7% and 86.7%, respectively). Conclusions: Probe-based confocal laser endomicroscopy may be effective for the diagnosis of pancreatic diseases as adjunct modality. It requires technical learning and further evaluation of its usefulness.