CT findings of gallbladder metastases: emphasis on differences according to primary tumors.
OBJECTIVE
To describe computed tomography (CT) features of metastatic gallbladder (GB) tumors (MGTs) from various primary tumors and to determine whether there are differential imaging features of MGTs according to different primary tumors.


METHODS
Twenty-one patients who had pathologically confirmed MGTs and underwent CT were retrospectively enrolled. Clinical findings including presenting symptoms, type of surgery, and interval between primary and metastatic tumors were recorded. Histologic features of primary tumor and MGTs including depth of invasion were also reviewed. Imaging findings were analyzed for the location and morphology of MGTs, pattern and degree of enhancement, depth of invasion, presence of intact overlying mucosa, and concordance between imaging features of primary and metastatic tumors. Significant differences between the histologies of MGTs and imaging features were determined.


RESULTS
The most common primary tumor metastasized to the GB was gastric cancer (n = 8), followed by renal cell carcinoma (n = 4) and hepatocellular carcinoma (n = 3). All MGTs (n = 21) manifested as infiltrative wall thickenings (n = 15) or as polypoid lesions (n = 6) on CT, similar to the features of primary GB cancers. There were significant differences in the morphology of MGTs, enhancement pattern, enhancement degree, and depth of invasion according to the histology of primary tumors (p < 0.05). Metastatic adenocarcinomas of the GB manifested as infiltrative and persistently enhancing wall thickenings, while non-adenocarcinomatous metastases usually manifested as polypoid lesions with early wash-in and wash-out.


CONCLUSIONS
Although CT findings of MGTs are similar to those of primary GB cancer, they are significantly different between the various histologies of primary tumors.
Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
Won Seok
WS
Choi
Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
Se Hyung
SH
Kim
Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
Eun Sun
ES
Lee
Department of Pathology, Seoul National University Hospital, Seoul 110-744, Korea.
Kyoung-Bun
KB
Lee
Department of Internal Medicine, Inje University Seoul Paik Hospital, Inje University College of Medicine, Seoul 100-032, Korea.
Won Jae
WJ
Yoon
Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
Cheong-Il
CI
Shin
Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
Joon Koo
JK
Han
D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary; D003937:Diagnosis, Differential; D005260:Female; D005706:Gallbladder Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary*; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology; D008113:Liver Neoplasms / Q000473:pathology; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology; D014057:Tomography, X-Ray Computed
CT; Gallbladder; MRI; Metastasis; Neoplasms