Abstract
Intracholecystic papillary neoplasm (ICPN) is a rare premalignant lesion of the gallbladder, and its natural history remains incompletely understood. We report a case of ICPN presenting as a small gallbladder polyp with progressive growth. A 56-year-old woman was found to have a gallbladder polyp measuring 7.6 mm, which increased to 11.2 mm over 2 years and 8 months. Contrast-enhanced computed tomography demonstrated a papillary lesion with enhancement. Laparoscopic cholecystectomy was performed. Histopathological examination revealed pyloric gland-type ICPN with low-grade dysplasia without invasive carcinoma. Immunohistochemical analysis showed positivity for MUC6 and MUC5AC, supporting gastric-type differentiation. No recurrence has been observed during postoperative follow-up.This case suggests that progressive growth, papillary morphology, and enhancement characteristics may indicate neoplastic potential even in gallbladder polyps initially measuring < 10 mm, suggesting the importance of careful follow-up and timely surgical intervention.