Organ-specific concept and controversy for premalignant lesions and carcinogenesis of gallbladder cancer.

An analysis of premalignant lesions, risk factors and models of carcinogenesis of gallbladder cancer (GBC) involves the concept of organ specificity. In GBC, the dysplasia-carcinoma sequence and metaplasia-dysplasia-carcinoma sequence are considered to be more important models of carcinogenesis than the adenoma-carcinoma sequence. Cholecystectomy is recommended for gallbladder polyps ≥1.0 cm, and all pre-invasive adenomas and papillary neoplasms ≥1.0 cm are defined as intracholecystic papillary-tubular neoplasms (ICPTNs). Although adenomyomatosis (ADM) and xanthogranulomatous cholecystitis (XGC) are controversial lesions, a knowledge of their clinicopathological features would help clinicians to manage gallbladder lesions associated with ADM or XCG.