Most cancer is still treated with surgery, chemotherapy and radiation. While these often do the job, doctors can’t always predict who will respond. And because chemo and radiation kill healthy cells, too, they can have debilitating side effects. But as scientists decode the DNA of tumors, they’re able to target cancer more precisely. Here’s the scoop on the latest treatments.

They take aim at the source of cancer.
The new drugs are directed at specific genetic glitches that “drive” a person’s cancer. (It’s more of a laser-guided missile than an atomic bomb.) This allows doctors to target mutations in tumors rather than just in the organ of origin (breast or lung, for example). Bonus: These treatments often have fewer side effects.

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Cancer can be something you live with.
Although the drugs can produce quick, dramatic responses, they aren’t necessarily cures. That’s because the cancer, wily and adaptable, may eventually find another way to grow, and a new drug will have to be deployed, explains James Gulley, M.D., director of the National Cancer Institute’s Medical Oncology Service. Still, these drugs can be used to hold off cancer for months, even years. When it comes to someone you love, any extra time matters.

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Your immune system's a powerful tool.
You may have heard of immunotherapy—it’s an emerging treatment that “releases the brakes” on the immune system so it can attack cancer in the body. About 15 to 25 percent of patients in studies are responding, says Dr. Gulley, offering hope for those like Stefanie Joho. At 22, the former Gawker staffer was diagnosed with colon cancer. After two surgeries and two regimens of chemo, she still had an inoperable tumor in her abdomen. Joho joined a clinical trial for the immunotherapy drug Keytruda and started to feel better almost immediately. A year later, her tumor has shrunk and her status is stable.

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Treatment is getting more accessible.
About 20 percent of patients are eligible for targeted therapy, said Dr. Keith Flaherty, director of clinical research at Massachusetts General Hospital Cancer Center. That number jumps to 40 percent at major medical centers—and will only grow as more research is done.

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