AUA 2017: Can looks deceive? Not all clinically “cystic” renal masses harbor indolent biology
Boston, MA (UroToday.com) In this study by investigators from Fox Chase Cancer Center, the surgical pathology from cystic renal masses were examined. Traditionally cystic renal cell carcinomas are thought to be clinically indolent. As such, it was suggested that they should be classified according to a distinct pathologic staging system. However, current imaging modalities are limited in reliably distinguishing cystic renal cell carcinoma from more aggressive mimics. The investigators sought to describe the rate of “false negatives” in the CT’s ability to describe these cystic mimics. In total, 105 pathologic specimens of cystic masses were identified. Maximum diameter was 4cm, with 72.4% of the masses described as Bosniak 3-4 cyst on CT scan. Of all cystic masses examined histologically, 26.7% harbored high grade tumors. Increasing Charlson Comorbidity Index was found to be associated with high grade RCC.
The authors concluded that a better understanding of the cystic RCC’s needs to be delineated prior to formulating the new classification schema. The importance of the limitations of the current imaging modalities in distinguishing cystic RCC’s from some papillary RCC’s was highlighted in the discussion. Until we are equipped with better imaging modalities to clearly define cystic RCC, it would be unwise to classify these lesions according to a schema reflecting more indolent behavior.
Presented by: Benjamin Ristau, MD
Written By: Roger Li MD Urologic Oncology Fellow, UT MD Anderson Cancer Center @UrogerliMD
Ashish M. Kamat MD Wayne B. Duddlesten Professor, UT MD Anderson Cancer Center
at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA