Diagnosis of malignant biliary obstruction: pondering over the ERCP, MRCP and histology

Objective To compare the diagnostic accuracy of endoscopic retrograde cholangiopancreatography (ERCP), magnetic resonance pancreatography (MRCP) and histological examination for malignant biliary obstruction. Methods This retrospective study included patients admitted for biliary obstruction caused by biliary tree malignancy that underwent ERCP, MRCP and histological examination. Data were collected from the medical records. The primary endpoints were the area under the receiver operating characteristic (AUROC) curve value, sensitivity, specificity and overall diagnostic accuracy of the three procedures in terms of a final diagnosis of obstructive biliary malignancy; and the agreement between ERCP, MRCP and histological examination with the final diagnosis. Results A total of 160 patients were included in the study (85 males, 53.1%; mean +/- SD age, 69.31 +/- 10.96 years). Considering the final diagnosis, the performance of MRCP, ERCP and histology in assessing biliary tumours produced AUROC values of 0.88 (95% confidence interval [CI] 0.75, 0.90), 0.94 (95% CI 0.85, 0.99) and 0.80 (95% CI 0.70, 0.82), respectively. ERCP presented higher sensitivity, overall diagnostic accuracy and agreement with the final diagnosis than MRCP and histological examination. Conclusion These current data suggest that invasive methods such as ERCP with biopsy remain more reliable than non-invasive methods.