in november , 2007 , a 48-year - old woman presented in our clinic with a four - day history of colicky pain in the right upper quadrant radiating to the back . she had a history of nephrectomy and adrenalectomy for right sided renal cell carcinoma ( rcc ) in 2002 . since then all yearly follow ups consisting of abdominal sonography and ct - scan were without pathological findings . physical examination revealed axillary temperature of 37.8 c , regular heart beat ( 84 beats / min ) without heart murmur , and normal breath sounds . examination of the abdomen revealed tenderness in the right upper quadrant , positive murphy 's sign and unremarkable bowel sounds . laboratory analysis showed a slight thrombopenia with 139.00/nl and haemoglobin of 10.9 g / dl . all other laboratory values were within normal limits , there was no cholestasis and no laboratory signs of infection . ultrasound showed a wall thickness of the gallbladder > 6 mm , consistent with an enlargement of the organ and hyperplasia of its wall . further sludge in the lumen and a light retention of effusion around the gallbladder was noted ( figure 1 ) . all other organs showed no pathological finding in the pre - operative ultrasound . because the acute symptomatic dictated an operation the patient underwent cholecystectomy which was planned laparoscopic but extended to conventional cholecystectomy because of multiple post - nephrectomy adhesions in 2002 . additionally sludge in the lumen ( blue marks ) and a light retention of effusion around the gallbladder was noted . histopathologic examination revealed a metastatic tumour which appeared macroscopically as a 2.5  2  1.5 cm polyp at the neck of the gallbladder ( gb ) . histopathology showed clear cells of renal carcinoma with delicate vascular stroma as already seen in the primary tumour of the nephrectomy specimen ( figure 2 ) . an abdominal ct - scan showed additional space occupying lesions in the pancreas and the left kidney . as this was interpreted as advanced metastatic renal cell carcinoma a palliative therapy with sorafenib ( nexavartablets 2  200 mg / d , bayer pharmaceuticals corp . ) was initiated . although sunitinib would be preferred by most oncologists as first line treatment sorafenib was chosen because of the favorable profile of side effects , especially with respect to fatigue . histopathological examination showed clear cells of renal carcinoma ( left ) and regular gall - bladder epithelium ( right ) ( haematoxylin and eosin stain ;  40 magnification ) . renal cell carcinoma ( rcc ) is a rare tumour accounting for 3% of all adult malignancies . it has a high metastatic potential with 25 - 57% metastatic disease at time of initial presentation . metastatic rcc has a poor prognosis with 1-year survival of less than 50% , 5 year suvival of 5 - 30% , and 10 year survival of 0 - 5% . rcc is known to metastasize mainly to the lung , bone , brain , liver , or adrenal glands . rcc metastases to the gallbladder are very unusual , only a few case reports are available in the literature of surgically resected metastasis documenting this rare localization . diagnosis of gall bladder metastasis was more often metachronous than synchronous . in the reviewed cases metachronous tumours were detected from 3 months to 27 years after initial diagnosis . however the vast majority is detected at autopsy . in a study by bennington et al . the incidence of gallbladder metastasis of rcc was reported to be 0.57% ( 3 out of 523 autopsies ) . in another study weiss gallbladder metastasis have been reported from other primary tumour , melanoma being the most frequent followed by lung , oesophagus , pancreas and colon carcinoma . metastasis from extraperitoneal organs such as the kidney , breast , skin and lung are described to primarily follow a hematogenous route . willis reported that hematogenous metastasis to the gallbladder initially begin with small flat submucosal nodules which then grow as pedunculated tumors , being rarely greater then several mililimeter in size resembling primary gb carcinoma . as in our patient , metastatic rcc to the gallbladder may produce symptoms mimicking cholecystitis which is an uncommon and unusual clinical presentation of metastatic disease . for primary gallbladder malignancies in general and especially for secondary gallbladder metastasis , conventional diagnostic methods including history , physical examination and sonography are nonspecific . although color doppler sonography and ct findings have been described for metastatic renal cell carcinoma to the gallbladder they are still unspecific as metastasis show a broad variety of presentation . hypervascularity has been reported to be a sign useful in distinguishing metastatic gb tumor of rcc from primary gb tumor which is described to be not so hypervascular . as a conclusion from this case , patients with a history of rcc ( even after several years of tumour free disease ) and pain in the right upper quadrant deserve a high index of suspicion regarding gall bladder metastasis which should be considered as a rare but possible cause . additionally , a pre - operative ct - scan may be considered which potentially alters further therapy . stathis philippou , chief of the department of pathology , augusta krankenanstalt , academic teaching hospital of the ruhr - university bochum , for providing the histologic image .
renal cell carcinoma constitutes about 3% of adult malignancies . 
 it has a high metastatic potential associated with synchronous or metachronous metastatic disease . 
 further , it is known to metastasize mainly to the lung , bone , brain , liver , or adrenal glands . in very rare cases it can metastasize to the gallbladder mimicking acute cholecystitis on clinical exam . in this case 
 we present a patient who developed a gallbladder metastasis five years after a renal cell carcinoma mimicking acute cholecystitis .