title: Renal cell carcinoma with unusual metastasis to the gallbladder.
abstract: Gallbladder involvement in patients with renal cell carcinoma (RCC) is extremely rare. We present a report of a 61-year-old man with a synchronous RCC metastasis to the gallbladder presenting as an intraluminal polypoid mass simulating primary gallbladder carcinoma. Enhanced abdominal computed tomography demonstrated a well-enhanced polypoid lesion in the gallbladder. Intraoperative rapid pathological examination of the gallbladder tumor showed clear cell-type cancerous cells. Microscopically, tumor cells of both the resected kidney and gallbladder had round uniform nuclei, clear cytoplasm, and well-defined cytoplasmic borders, forming alveolar patterns. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) and carcinoembryonic antigen (CEA), which is usually positive in primary clear cell carcinoma of the gallbladder. Therefore, the final diagnosis was RCC with a synchronous gallbladder metastasis.
authors.affiliation: Department of Gastroenterological Surgery, Chiba Cancer Center Hospital, 666-2 Nitona-chou, Chuo-ku, Chiba 260-8717, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nojima
authors.forename: Akihiro
authors.initials: A
authors.lastname: Cho
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Matsuo
authors.initials: M
authors.lastname: Nagata
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Takiguchi
authors.forename: Osamu
authors.initials: O
authors.lastname: Kainuma
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Souda
authors.forename: Hisashi
authors.initials: H
authors.lastname: Gunji
authors.forename: Akinari
authors.initials: A
authors.lastname: Miyazaki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ikeda
authors.forename: Ikuko
authors.initials: I
authors.lastname: Matsumoto
authors.forename: Takehide
authors.initials: T
authors.lastname: Asano
authors.forename: Munemasa
authors.initials: M
authors.lastname: Ryu
authors.forename: Naoki
authors.initials: N
authors.lastname: Nihei
authors.forename: Masayuki
authors.initials: M
authors.lastname: Maruoka
mesh_terms: D002292:Carcinoma, Renal Cell / Q000556:secondary* / Q000601:surgery; D002763:Cholecystectomy; D005706:Gallbladder Neoplasms / Q000556:secondary* / Q000601:surgery; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary; D009392:Nephrectomy