A gallbladder tumor revealing metastatic clear cell renal carcinoma: report of case and review of literature

The virtual slides’ for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8956897238238989 webciteMetastatic tumors to the gallbladder are uncommon. The most common metastatic tumors to the gallbladder are metastatic melanomas and metastatic carcinomas from stomach, pancreas, ovary, bile ducts, colon and breast [1]. Metastatic renal cell carcinoma in the gallbladder is extremely rare, with reported frequencies of less than 0.6% in large autopsy reviews [2]. Renal cell carcinoma is a rare tumor accounting for 3% of all malignancies in adults and 85% of primary renal tumors. However, this tumor has a great propensity for metastasizing synchronously or metachronously to various anatomic sites [3]. We report a case of intraluminal polypoid metastasis of clear cell renal cell carcinoma in gallbladder mimicking gallbladder polyp and revealing the renal carcinoma and reviewed the reported 40 cases. The clinico-pathologic features and differential diagnosis are discussed.A 55-year-old woman presented with severe right hypochondrium pain, with weight loss and alteration of her general condition, lasting for 6 months. She showed no urological signs, especially no hematuria, no pain, and no flank mass. She had no past history in particular. Neither physical examination nor laboratory examination revealed any significant findings. Abdominal ultrasonography showed a 2.6 cm diameter intraluminal polypoid hyperechoic mass in the gallbladder. Color Doppler ultrasonography examination demonstrated vessels in the mid-portion of the mass. Computed tomography scan confirmed the presence of a gallbladder tumor that appeared as an enhancing pedunculated tumor within the gallbladder, without thickening of the gallbladder wall. The tumor seemed to be attached to the edge of the liver with no macroscopic extension to the liver parenchyma (Figure 1). Furthermore, TDM scan showed a cortical fleshy nodule of the right kidney, measuring 2.2 cm, with no involvement of