A new study suggests an interesting alternative in the fight against cancer: Rather than try to eliminate the disease entirely, focus on controlling it. The treatment is known as adaptive therapy, and if the human results resemble those observed in mice, it could change the way we view cancer treatment.

The radical approach to cancer treatment tackles one of the most basic concepts of evolution — adaptation. In the the face of a persistent threat, a species will either become extinct or eventually evolve mutations to help it adapt to the threat. This is why so many bacterial infections are now resistant to antibiotics. Cancer tumors are no exception. When chemotherapy destroys cancer cells, the new ones that grow to replace those lost often have a mutation that gives them a resistance to the chemotherapy, Time reported.  

In theory, doctors will administer adaptive therapy to patients by giving them low doses of chemotherapy. They would then use magnetic resonance imaging to calculate cancer cell populations and medication dosages in an effort to keep the cancer at bay instead of trying to completely wipe it out. This controls the cancer’s spread but also reduces the chance that cells will adapt to the treatment. For their study, published in Science Translational Medicine, the team tested their technique on three groups of mice with two different forms of breast cancer: Triple negative and ER+.

Each group was given a different form of treatment: Either the standard maximum drug dose, adaptive therapy with a significantly lower drug dose, or an alternative adaptive therapy with skipped doses. Results revealed that all three treatments did initially stabilize tumor growth. In the long term, however, the low-dose adaptive therapy was the only treatment that continually stabilized tumor growth, a result seen in up to 80 percent of those animals. In addition, mice on this therapy lived significantly longer than those on the other two treatments.

“These results surprised me a little,” lead author Dr. Robert Gatenby told Time. “I was concerned that although we might see some benefit, that we wouldn’t see a lot of benefit and that we may not be able to have an impact on the tumor because it’s growing so fast at the beginning.”

The team then monitored cancer cell growth at the tumor site using a computed algorithm calculator similar to one used by farmers to control crop pests, Science Alert reported. This way the team was able to kill off enough of the cancer cells to keep a patient healthy without activating the mutation of chemo-resistant cells.

At the moment, the treatment has only been used on mice, and although the results are promising, it will need to be repeated on humans before we can begin to get truly excited. Gatenby and his team are currently testing the treatment on a group of men with prostate cancer and expect results soon.

Source: Gatenby RA, Enriquez-Navas PM, Kam Y, et al. Exploiting evolutionary principles to prolong tumor control in preclinical models of breast cancer. Science Translational Medicine . 2016