The basics of von Hippel-Lindau disease
Kristie L. Kahl: Can you just explain what VHL is?
Stacy Lloyd: VHL is the abbreviation for von Hippel Lindau disease. And it’s a rare genetic disorder characterized by blood vessel tumors that can grow in areas of the body including the brain, eyes, kidneys, adrenal glands, and many more. These tumors can be benign or cancerous. And the disease itself is the result of a change or mutation in the VHL gene, which is a tumor suppressor gene that everyone has. Eighty percent of VHL cases are passed on from a parent. And about 20% of adult cases are actually considered de novo, meaning it was not inherited by a parent, but that individual is actually the first in (their) family to have the disease. And then also something that I think is interesting about this, even though there are a few different mutations in this gene that can cause VHL, there really is no way to tell exactly how it will manifest in a person. or a family. Early diagnosis and regular monitoring are therefore very important.
Kristie L. Kahl: What types of cancer can VHL specifically affect?
Stacy Lloyd: VHL is therefore a tumor predisposition syndrome, which means that people with VHL are much more likely to develop certain types of tumors multiple times during their lifetime. Compared to people in the general population, some VHL tumors are rare and unlikely to occur in the general population. However, this is not the case for all tumors linked to VHL. So, for example, renal cell carcinoma with clear cells. CcRCC, for short, is a type of kidney cancer that occurs in up to 60% of patients with VHL, but it also accounts for about 80% of all kidney cancers in the general population. The biggest difference is that in VHL these tumors appear much earlier than in the general public and are more likely to occur in both kidneys than one sided. This is quite significant, because the scientific community has recognized that better treatments and a cure for VHL would have a direct impact on people in the general population. Indeed, in 2019, the Nobel Prize in Medicine was awarded to Dr. Bill Kaelyn, and two of his colleagues for their work on identifying the link between the VHL gene and kidney cancer, which in fact resulted in the development of new and extremely promising technologies. therapies. So we really hope that the research being done in the VHL space could really lead to a cure for kidney cancer as well as other types of disorders and cancers.
Kristie L. Kahl: How do we test for vhl?
Stacy Lloyd: There are several tests that are part of our regular monitoring as patients, including eye exams, MRIs, CTS, audiology, exams, among others, and these are about the most common. That said, the only way to actually confirm a diagnosis of VHL is through genetic testing,
Kristie L. Kahl: What should prompt someone to make sure they get tested for VHL?
Stacy Lloyd: So if there is a family member who has already tested positive for VHL, that should prompt other family members who may be affected to get tested as well. In my case, personally, after my second manifestation in the form of a paraganglioma, which is just a kind of free-floating tumor in the abdomen. I had genetic testing for VHL. And I was the first in my family to be tested. And that obviously came back positive and it really started a round of testing of my family members and actually eight of us in total have been confirmed to have the disease.
For a patient who has no family history of the disease, there are certain criteria that help determine when a patient should be referred for genetic testing and counseling. For example, anyone with mangioblastoma of the brain or spine or pheochromocytoma, which is a tumor of the adrenal gland, or that clear cell renal cell carcinoma, especially if the patient is younger and presents bilaterally . All of these criteria, however, can be found on the VHL Alliances website.
Kristie L. Kahl: If someone tests positive, what are the current recommendations?
Stacy Lloyd: Surveillance is extremely important for the early detection of manifestations. Many tumors can be identified very early on, and when they are very small, and in fact just watched closely until they start causing problems or require treatment, or need to be removed. So if patients are watched very closely, it is much more likely that they will achieve better results and a better quality of life.