[909] Renal Cell Carcinoma Shows Ethnic-Related Histological Patterns

HB Wang, J Cohen, AD Nicastri. State University of New York Downstate Medical Center, Brooklyn, NY

Background: Renal cell carcinomas (RCC) account for the most common renal cancers in adults. Cytogenetic findings and new molecular markers have been included in the WHO 2004 renal tumor classification for the guidance of diagnosis, prognosis, and therapy of this disease. Tobacco, obesity, hypertension, unopposed estrogen therapy, chemical agents, and end-stage renal disease have been shown to be risk factors associated with RCC. But no epidemiologic data regarding incidences of RCC of various histological types in different racial groups have been reported. Our aim was to review clinico-pathologic data in a cohort of RCC cases and to determine if there are any differences among racial/ethnic populations.
Design: Ninety-nine RCC cases have been reviewed between 2002 and 2008 from two hospitals affiliated with State University of New York in Brooklyn, where a mixed ethnic population exists. New WHO 2004 Classification is applied to the review of the pathological findings.
Results: Clear cell carcinoma remains the most common RCC accounting for 52.53% (52/99) of all the cases, followed by papillary RCC 34.34% (34/99), chromophobe RCC 7.07% (7/99), acquired cystic disease-associated RCC 2.02% (2/99), collecting duct carcinoma 1.01% (1/99), multilocular cystic RCC 1.01% (1/99), medullary RCC 1.01% (1/99), and one pediatric RCC with unconventional features. Clear cell RCC, as has been reported, is the most common RCC in white population (79.49%, 31/39) and other non-black ethnic groups; while papillary RCC is significantly prevalent in African Americans accounting for 59.26% (32/54) of all RCC cases in this population. Papillary RCC in African American patients accounts for the majority of this type of RCC among all cases (32/34). There are nearly two folds more type 1 than type 2 papillary RCC. Type 2 papillary RCC showed more unfavorable clinical courses than type 1 cases. More chromophobe RCC cases are seen in the whites than in the African Americans.
Conclusions: We reported for the first time that African Americans seem to have an significantly increased risk of developing papillary RCC than general population. This ethnic-related difference of histological presentations may reflect the complex underlying genetic and molecular basis of the pathogenesis of RCC.
Category: Genitourinary (including renal tumors)

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 103, Tuesday Morning