"Incidentally" discovered Von Hippel Lindau disease: an emerging clinical phenotype.

Increasing accessibility to genetic screening for cancer risk can lead to earlier surveillance and prevention, but with this comes the caveat of incidental identification of germline pathogenic gene variants. Here, we report a single institution case series of 6 otherwise healthy individuals with "incidental" Von Hippel Lindau (VHL) disease. These patients were found to have pathogenic germline variants in the VHL gene, after undergoing genetic testing for other purposes (5 for familial breast cancer risk and 1 to determine ancestry) but no VHL disease-associated tumors. The penetrance and expressivity of such incidental variants are not currently known, and therefore, no surveillance guidelines exist. Nevertheless, the association of these variants historically with high disease penetrance compels us to currently recommend active surveillance of their carriers with annual imaging of the brain, spine, and abdomen.