CUA 2018: Predictors of a Positive Genetic Test Result in Patients with a Suspected Hereditary Kidney Cancer Syndrome: Results from a Provincial Medical Genetics Unit

Halifax, Nova Scotia (UroToday.com) Andrea Kokorovic, MD, presented a study attempting to assess risk factors associated with a positive genetic test in a real-life cohort of patients referred to medical genetics for evaluation of hereditary renal cell carcinoma (RCC).

RCC has strongly been linked with hereditary kidney cancer syndromes. CUA guidelines recommend genetic referral for patients with RCC and high-risk features.1 There is very limited data regarding outcomes of these patients. There is a single center study from MSKCC suggesting that young age is a predictor for a positive genetic test result.2 High-risk features of RCC suggestive of a hereditary kidney cancer syndrome are shown in table 1.

Table 1 – RCC features suggestive of hereditary kidney cancer syndromes:
RCC_features_hereditary_Kidney_Cancer.png
Currently, there is limited data regarding the number and outcome of patients identified as being high-risk for hereditary kidney cancer syndromes that have been referred for genetic counseling. The CUA referral criteria are derived from expert consensus and lack of support from the literature.

The presented study aimed to determine the risk factors associated with a positive genetic test in a real-life cohort of patients referred to medical genetics for evaluation of hereditary RCC. The study flowchart is demonstrated in Figure 1. 

Figure 1 - Patient study flowchart:Patient_Study_Flow_Chart.png
Multivariable analysis demonstrated that family history and dermatologic findings were statistically significant predictors of a positive genetic result. Dr. Korokovic concluded that dermatologic findings and family history are the only predictors of a positive genetic test in patients undergoing evaluation for hereditary RCC. This is the largest study published to date on this important issue and suggests that current referral criteria may be too broad for application in real life patient population. In any case, further evaluation with prospective trials is warranted.

Presented by: Andrea Kokorovic, Dalhousie University, Halifax, Canada

References:
1. Reaume M, Graham GE, Tomiak E, et al. Canadian guideline on genetic screening for hereditary renal cell cancers. Can Urol Assoc J 2013; 7: 319-23. https://doi.org/10.5489/cuaj.1496
2. Stratton K et al. Outcome of genetic evaluation of patients with kidney cancer referred for suspected hereditary cancer syndromes. Urologic Oncology 2016; 34: 238e1-238e7

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, Twitter: @GoldbergHanan at the 73rd Canadian Urological Association Annual Meeting - June 23 - 26, 2018 - Halifax, Nova Scotia