Genetic Testing
The same question dogs everyone who gets cancer: Where did it come from? It’s not a critical question because we already have cancer, and our focus is on getting rid of it.
Yet I wanted to know. If my cancer came from an outside source and is environmentally-caused, like exposure to a lawn herbicide or a crop pesticide, which seems to be a problem in agricultural areas, especially in Iowa and Illinois, then I want to stay away from it. Were there industrial carcinogens in my drinking water from fracking? Maybe a pathogen snuck in through a cut in my skin.
Or did I cause my cancer by standing for years too close to a 1980s microwave as I reheated my coffee every morning? Maybe I have an unhealthy lifestyle. Everyone knows that if you smoke, you shouldn’t be surprised to develop lung cancer. Was there an outside cause-and-effect for my prostate cancer?
Perhaps my cancer is punishment for some moral error, a physical weakness, my repression of passions, or enjoyment of too many passions that enabled cancer to start growing, as people believed about tuberculosis in the 19th century. Maybe what damaged my cells and turned them into cancer cells was stress, and I should have reduced my tension by celebrating life more like my mother who liked to eat ice cream together in the evening, and been less like my dad who felt that there were always chores to be done. Perhaps working all the time, and not getting a full night sleep, wasn’t healthy and allowed stress to build up in my cells until some began to crackle, pop, and rebel.
Another possibility is that I inherited my cancer. To help me find out, I meet with geneticist Judy Williamson at the Illinois Cancer Care Center to do germline / genetic testing and see if I received a prostate cancer-causing gene from one of my male relatives, as well as find out if I have any of the seventy genes that are known to cause other cancers, like pancreatic, breast, skin, and colorectal. If I do, then I could take proactive measures.
I can tell that Judy gets excited about genetics because when we sit down and I start talking about the history of cancer in my family, her eyes light up. My family’s history wasn’t easy to compile because my parents, and all my older relatives, are dead. No one is left alive who actually knows. My dad did have prostate cancer when he was in his 90s, but he was old. I don’t think it was serious enough to be treated, and he died of something else.
Besides my grandmother, who possibly had both breast and colon cancer, there’s some disagreement here, I found a note that two of my aunts may have had colon cancer. Three cases of colon cancer in close relatives seem significant. Judy will look for those genes, as well, and she will do a polygenic risk score, which is when common variants work together to increase risk. I’m sent off to give blood for the test, and that is sent off to be analyzed.
Judy says there are twenty-two genes known to be connected to the development of prostate cancer, but there are nine genes that are most at fault because they have stronger penetrations. Two weeks later the results come back. I haven’t inherited a gene for prostate cancer, or any of the other known cancer-causing ones, including the BRCA gene that could cause a second prostate cancer to grow after the first one’s been eradicated. Judy says that even if I had inherited a cancer-causing gene, this doesn’t mean it would become active.
If my cancer is not hereditary, and if it’s not environmentally-caused, the third possibility is that it’s somatic in origin, that is, rising on its own inside my body. Judy says there are two kinds of mutations that lead to cancer. Germline / genetic mutations are ones you are born with (hereditary). Somatic mutations happen within the cells, and a sobering 85% of all cancers begin here. The tissue from my prostate biopsy can be tested for somatic changes.
On a recent webinar by the Prostate Cancer Foundation, the oncologists say that even if your cancer hasn’t metastasized, if it’s aggressive and high risk, like mine is, then you should have somatic (molecular) testing done. I ask my medical oncologist about doing the test, he agrees, and sets the procedure up to test my blood and prostate tissue using next-generation sequencing. Unfortunately, the results are incomplete because the tissue sample from my original biopsy had degraded too much. I’m not keen on having a new biopsy just to get fresh tissue to test because getting the first samples wasn’t a pleasant experience. The blood sample part of the test gives us some information to work with. If my cancer starts to come back, I imagine that we’ll do a new biopsy and we can test that.
If the tissue test had been successful, I would know what kind of cell mutations I had, and which targeting therapy drug would be most effective in preventing metastasis. This kind of information is vitally important when you have breast cancer because one kind of treatment works great with one mutation but does diddly squat for a different mutation. I don’t think research into prostate cancer has come this far.
Genetic testing can be life-saving. If we knew we had a gene that could cause a specific cancer, then we could watch for symptoms of that cancer beginning and begin treatments while a cure is still possible. I may never know what caused my cancer to take root, but at least it’s not hereditary, and my brother and his son can relax.
Find out the history of cancer in your family while the people who know are still alive.
© 2026 Mark Liebenow
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