Hello. Thanks for the question. The ERCP test can identify issues including cancer of the gallbladder. https://www.cancerresearchuk.org/about-cancer/gallbladder-cancer/getting-diagnosed/tests-diagnose/ercp. An MRI or CT scan are probably more commonly used. https://www.cancer.org/cancer/gallbladder-cancer/detection-diagnosis-staging/diagnosis.html
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