Pengjie Wu,Dong Wei,Liqing Zhng,Shumin Deng, Gng Zhu,c,Jinye Wng,*

aDepartment of Urology,Beijing Hospital of the Ministry of Health,Beijing,China

bBeijing Institute of Geriatrics,Ministry of Health,Graduate School of Peking Union Medical College, Beijing,China

cDepartment of Urology,Cancer Hospital of Chinese Sciences and Peking Union Medical College, Beijing,China

CLINICAL IMAGE

Clear cell renal cell carcinoma located in sinus renalis confused with renal pelvis mass in image

Pengjie Wua,b,Dong Weia,Liqing Zhanga,Shumin Denga, Gang Zhua,b,c,Jianye Wanga,b,*

aDepartment of Urology,Beijing Hospital of the Ministry of Health,Beijing,China

bBeijing Institute of Geriatrics,Ministry of Health,Graduate School of Peking Union Medical College, Beijing,China

cDepartment of Urology,Cancer Hospital of Chinese Sciences and Peking Union Medical College, Beijing,China

A 58-year-old Chinese woman presented with a mass in right renal pelvis incidentally detected by ultrasonography (Fig.1A).No positive signs were found by physical examination,and urinalysis was also normal.Enhanced computed tomography(CT)of abdomen displayed a polycystic mass of 2.3 cm?2.1 cm?1.6 cm in right sinus renalis(Fig.1B and C)with ample blood perfusion in arterial phase(Fig.1B) and less perfusion in venous phase(Fig.1C).CT images of excretory phase were not obtained.A retrograde pyelography was then performed and did not f i nd a def i ned mass image in the pelvis(Fig.1D).Urinary cytology was negative from three urine samples including one pelvic urine sample. Our preliminary diagnosis was renal cell carcinoma(RCC)in right renal pelvis.We decided to perform laparoscopic nephroureterectomy for radical incision of the tumor. During operation we ligated the ureter f i rst to prevent the dissemination of transitional cell carcinoma.Incision of the removed kidney displayed a polycystic tumor with a complete psuedocapsule near the fat tissue in renal pelvis (Fig.1E and F).Intraoperative fi ndings supported the diagnosis of RCC.Pathological diagnosis was clear cell RCC (Fig.1G),which invaded renal sinus(peripelvic)fat but not beyond the Gerota’s fascia.

Before operation,solely based on the image of the mass fi lling the renal pelvis,it was dif fi cult to be differentiated from transitional cell carcinoma.We speci fi cally noticed the CT images that blood perfusion in the mass increased in arterial phase and quickly decreased in venous phase. Combined with other clinical evidences,we made the diagnosis of RCC.According to the 2014 EAU guidelines,CT urography should include images at excretory phase for the patients suspected of urothelial carcinoma[1].As we know, transitional cell carcinoma in renal pelvic is intensi fi ed only slightly during enhanced CT scanning.Collecting duct carcinoma(CDC)tumors should also be considered when the mass is localized in sinus renalis.However,CDC is hypovascular and usually invades medullary area[2],but clear cell RCC is mostly hypervascular and often locates in cortex area.Therefore,if there is no proof for transitional cell carcinoma and the mass is intensi fi ed signi fi cantly during CT scanning,radicalnephrectomyshouldbeconsidered. Otherwise,ureterorenoscopy should be performed at fi rst to avoid unnecessary nephroureterectomy[3].

Conf l icts of interest

The authors declare no conf l ict of interest.

Acknowledgments

We are grateful to the patient who participated in this study.

[1]Gakis G,Witjes JA,Compe′rat E,Cowan NC,De Santis M, Lebret T,et al.EAU guidelines on primary urethral carcinoma. Eur Urol 2013;64:823e30.

[2]Pickhardt PJ,Siegel CL,McLarney JK.Collecting duct carcinoma of the kidney:are imaging f i ndings suggestive of the diagnosis?AJR Am J Roentgenol 2001;176:627e33.

[3]Jeong YB,Kim HJ.Is it transitional cell carcinoma or renal cell carcinoma on computed tomography image?Urology 2012;79: e42e3.

Received 27 November 2014;received in revised form 6 February 2015;accepted 23 March 2015 Available online 18 June 2015

*Corresponding author.Department of Urology,Beijing Hospital of the Ministry of Health,Beijing,China.

E-mail address:wjy@bjhmoh.com(J.Wang).

Peer review under responsibility of Shanghai Medical Association and SMMU.

http://dx.doi.org/10.1016/j.ajur.2015.06.001

2214-3882/a2015 Editorial Off i ce of Asian Journal of Urology.Production and hosting by Elsevier(Singapore)Pte Ltd.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).