Outcome of genetic evaluation of patients with kidney cancer referred for suspected hereditary cancer syndromes.

OBJECTIVE: To analyze patients with kidney cancer referred for evaluation at a high-volume genetics service at a comprehensive cancer center and identify factors associated with positive tests for hereditary cancer syndromes. METHODS: A retrospective review of patients referred to the Clinical Genetics Service at Memorial Sloan-Kettering Cancer Center was performed, and patients with a personal history of kidney cancer were identified. Patient and disease characteristics were reviewed. In all, 4 variables including age at diagnosis of kidney tumor, presence of syndromic manifestations, family history of kidney cancer, and number of primary malignancies were evaluated for association with positive test results in 2 groups: patients tested for renal cell carcinoma syndromes and Lynch syndrome. Guidance for genetic testing strategy in patients with kidney cancer is provided. RESULTS: Between 1999 and 2012, 120 patients with a history of kidney cancer were evaluated by the Clinical Genetics Service. The mean age at kidney cancer diagnosis was 52 years (interquartile range: 42-63), with 57% being women. A family history of kidney cancer was reported by 39 patients (33%). Time between diagnosis of first cancer and genetic consultation was <1 year in 54%, 2 to 5 years in 23%, and>5 years in the remaining 23%. Overall, 95 patients were tested for genetic abnormalities with 27 (28%) testing positive. Testing for renal cell carcinoma (RCC)-related syndromes was performed on 43 patients, with 13 testing positive (30%). Lynch syndrome testing was positive in 9 patients (32%) after 28 were tested. In RCC-associated syndromes, young age of diagnosis was associated with positive test results. Conversely, syndromic manifestations and increasing number of primary malignancies were associated with positive Lynch testing. CONCLUSIONS: The discovery of inherited kidney cancer syndromes has provided a unique opportunity to identify patients at increased risk for cancer. Factors associated with positive genetic testing are unique to different syndromes. These data suggest that in kidney cancer patients evaluated for hereditary cancer syndromes, young age is associated with diagnosis of RCC syndromes, whereas syndromic manifestations and multiple primaries are found in Lynch syndrome. These results, along with clinical awareness, may be useful for practicing urologists to select patients with kidney cancer to refer for genetic counseling.