Doc: Radiation therapy doesn’t cause cancer to spread

Keith Roach
To Your Health

Dear Dr. Roach: My husband had prostate cancer in 2013. He was treated with radiation, and was thought to be cured. Well, one year later, he found out he had cancer in his liver. He lived eight months before going into hospice for his last 15 days.

Do you think the radiation of the prostate spread the cancer to his liver? If he had had only surgery, would the cancer not have spread? I am still grieving and questioning.


Dear B.V.: Both radiation and surgery can provide a good chance for cure in most patients with prostate cancer that is localized, meaning that it has not already spread. It is not clear which is better, and for any given man, radiation might be better than surgery, or vice versa, which is why the choice needs to be carefully individualized by the experts managing the prostate cancer, including a urologist, radiation therapist and possibly medical oncologist.

Radiation doesn’t cause cancer to spread, so I think you can stop feeling that your husband did not get the correct treatment. It’s likely that a few cancer cells had already spread to the liver before he got radiation treatment. (That is, if the liver cancer was indeed from the prostate, since you haven’t told me enough to know for sure that it was. Many cancers can spread to the liver. Hepatocellular carcinoma is the most common cancer of the liver itself.)

If he had elected to have surgery, the cancer cells still would have already been in the liver, he likely would have had the same outcome, and you probably would be wondering whether the surgery had caused the cancer to spread.

I have found that after someone passes from cancer, their family and loved ones often second-guess their treatment: What if they had gone to a better hospital? What if they had tried a different diet or supplements? There is an endless list of things you might have done to try to change the outcome. However, the vast majority of the time, there is nothing for a family member to blame him- or herself for. There is no situation so bad that adding guilt on top of it can’t make it worse, and the guilt doesn’t help anything.

I mentioned medical oncology – some early trials suggest that chemotherapy given in addition to radiation therapy may improve cure rates in some men with high-risk prostate cancer.

Dear Dr. Roach: I’m wondering about what I have read regarding blue-light emissions from flat-screen TVs, smartphones, computers and other devices. Blue light, so I have read, is deleterious to one’s eyesight in the long run, including contributing to insomniac or “night bird” behavior and possibly eye strain. I bought blue-blocking glasses, which, at the least, sharpen vision. Have you seen any evidence about the effect of blue light?


Dear E.L.: Blue light penetrates more deeply into the retina, so it is suspected that blue light might be more likely to damage the retina, increasing the risk for age-related macular degeneration. Blue light also has more powerful effects on the sleep-wake cycle, so blocking blue light at nighttime may reduce the adverse effects of light on sleep cycles.

Some authorities have suggested that blue light is more likely to cause eye strain. An alternative to blue-blocking lenses is to reduce the color temperature of the monitor to reduce blue light.

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