Gallbladder Intramucosal Carcinoma Arising in a Cholesterol Polyp: A Case Report

Abstract

Cholesterol polyp is the most common benign disease of gallbladder polyps, and is considered not to be the origin of malignancy. Herein, we report a rare case of a well-differentiated adenocarcinoma arising in a gallbladder cholesterol polyp. A pedunculated mulberry-like gallbladder polyp diagnosed with a cholesterol polyp preoperatively consisted of two distinct components macroscopically: a yellow-whitish lobulated lesion and a brownish irregular lesion. Microscopically, the former revealed to be a cholesterol polyp, but the latter demonstrated a well-differentiated adenocarcinoma. Even if imaging findings suggest a gallbladder cholesterol polyp, it is important to keep in mind that carcinoma can coexist like our case.

The New Perspectives Journal of Medicine

“…GP主要病理类型 GP可分为真性息肉(肿瘤性息肉)和假性息肉(非肿 瘤性息肉)两大类。前者包括胆囊腺瘤、间叶组织肿瘤、 腺癌等，后者包括胆固醇性息肉、炎性息肉、胆囊腺肌 症、增生性息肉等 (7,8) 。此外，影像学诊断的假阳性结果包 括粘附在胆囊壁上的结石、强回声胆泥和黏膜褶皱 (3) 。 2.1. 胆固醇性息肉和炎性息肉 胆固醇性息肉是最常见的病理类型，约占60~90%， 与胆固醇代谢紊乱有关，通常是由胆固醇在胆囊黏膜下 形成 (9,10) 。胆固醇性息肉不具有恶变潜能，但也有病例在 手术前仅发现胆固醇性息肉，术后病理证实其与腺癌共 存 (11) 。炎性息肉是胆囊炎症的一种表现形式，约占全部 GP的10%，同样不具有恶变潜能，病理特征是炎细胞浸 润和纤维化，其形成与继发于慢性炎症的局部上皮细胞 增殖有关 (8,9) 。 2.2. 胆囊腺肌症 胆囊腺肌症(gallbladder adenomyomatosis, GADM) 是一种退行性和增生性疾病，发病机制尚不清楚，其特征 是粘膜上皮肥大，陷入增厚的肌层的间隙，形成罗-阿窦 (Rokitansky-Aschoff sinuse, RAS)，窦内常形成结石或 胆固醇结晶 (12,13) 。目前尚无充分证据证明GADM就是癌前 病变，但当GADM继发胆囊结石和胆囊炎时，可能导致 异型增生和GC (14) 。 2.3.…”