Having an alteration in the VHL gene is what is know as a predisposition factor to certain kinds of tumors, including some specific cancers. Because there are so many well-organized resources for people with cancer, and because the concerns of people living with a chronic condition like VHL are so similar to those of people living with cancer, it is often an advantage to keep an eye on those services.
What is Cancer?
Cancer can be a frightening word. Families need to know that cancer can occur with VHL. However, with careful early monitoring and treatment, the worst possibilities of cancer may never occur.
Cancer is not one thing, it is a group of more than 100 different diseases. While each disease differs from the others in many ways, every cancer is a disease of some of the body’s cells. Cancer associated with VHL is limited to specific types.
Healthy cells that make up the body’s tissues grow, divide, and replace themselves in an orderly way. This process keeps the body in good repair. Sometimes, however, normal cells lose their ability to limit and direct their growth. They divide too rapidly and grow without any order. Too much tissue is produced, and tumors begin to form. Tumors can be benign or malignant.
- Benign tumors, such as VHL tumors of the brain, spine, and retina, are not cancerous and do not spread.
- Malignant tumors, like those which may occur in the kidney, are cancerous. They can invade and destroy nearby healthy tissues and organs. Cancer cells also can spread, or c, to other parts of the body and form new tumors.
Because VHL can cause malignant tumors in the visceral organ systems, it is considered one of a group of familial cancer susceptibilities, which are transmitted genetically. The objective is to find tumors early, watch for signs that a tumor is becoming aggressive in its behavior, and to remove the tumor before it invades other tissues. Since these tumors are inside the body, you need medical imaging techniques to find and watch them.
Not all tumors require surgery when they are found. Researchers are identifying multiple stages that cells go through before they know how to metastasize and plant themselves in other sites in the body. Think in terms of a dandelion, or other plant that sends seeds out into the air. A dandelion starts as a plant with a broad green leaf. It develops fuzzy little yellow flowers, a rather pretty little wildflower in the grass. The yellow flowers live for several days, and then turn into a white puff as the seeds develop. At a certain point the seeds release into the air and fly everywhere, planting new dandelions wherever they land. At this point they have seeded your lawn and your neighbor’s lawn.
The Dandelion Analogy
Think of the growth of a cancer tumor as a dandelion, the tumor is caused by a change in a single cell. This single cell, or seed, begins to grow and multiply, forming a tumor. That early tumor contains “cancer cells,” and if checked under a microscope even the early tumors contain “cancer cells,” in these early stages the cells have no idea how to plant themselves in other places. These are the stages where the tumor is “green” or “yellow” in dandelion terms. However, at a certain point in its growth cycle, it gains the power to propagate or to seed itself elsewhere—the dandelion turns white. Just as the trick with dandelions is to pick them while they’re yellow, the trick in removing kidney tumors is to take them out during that “yellow” phase—once they are big enough to be worth spending the risks and inconveniences of surgery, but before they gain the ability to propagate.
Research is going on to learn more about how to tell when a tumor is getting worrisome and requires action.