Caring Currents

Big News for Chemotherapy Patients: Timing is Everything

Last updated: Jan 28, 2009

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Image by laffy4k used under the creative commons attribution license.

Big news this week for those of us responsible for scheduling chemo appointments for ourselves or family members. New research conducted at the University of North Carolina at Chapel Hill revealed that the timing of chemo appointments may have an important effect on how well the drugs work to fight cancer.

In short, those taking some of the most common chemotherapy drugs are most likely to get well if they schedule their chemotherapy appointments first thing in the morning.   The reason? This is when the body's cell repair mechanism -- which can help cancer cells fight off the chemotherapy drugs -- is at the lowest ebb.

The drug used in the study was cisplatin -- considered by many to be a "miracle drug" since it cured Lance Armstrong of testicular cancer. However, cisplatin -- one of the main drugs used to treat colorectal cancer, lung cancer, ovarian cancer, and testicular cancer --  doesn't work for one in ten people who take it, and the new study may offer an explanation why.

For years, studies have suggested that the body's circadian rhythms appear to impact the effectiveness of chemotherapy drugs. But experts had no idea why this was so -- and lack of a clear explanation has kept most oncologists from recommending that cancer patients schedule chemotherapy appointments at specific times of day.

That's now going to change as a result of the new study , believes Aziz Sancar, a physician and professor of biochemistry and biophysics who led the research team. "I believe that within five years, all oncology clinics will use circadian rhythms as a factor when designing chemo regimens," he adds.

While his research was conducted in mice and he's just launching a study in humans, Sancar says if he were caring for a cancer patient, he wouldn't wait -- he'd talk to the doctor about careful timing of chemo appointments now. And experts believe the study has implications for many other  chemo drugs, which also may well turn out to be more effective at certain times of day.

One more thing. Because the cellular repair system Sancar studied prevents many types of DNA damage , experts are now looking at circadian rhythms and sun exposure. Perhaps avoiding the sun at certain times of day -- such as early in the morning -- could help us protect ourselves from skin cancer.   Stay tuned.