Now, a new drug that retrains the immune system can stop a tumor in its tracks.
Former TV reporter Neil Vicino covered many emergencies in his days on the job, but now he's fighting a personal battle.
"It kind of just snuck up on me," Vicino says.
After smoking for 40 years, cancer had invaded his lungs, and surgery was not an option.
But Vicino was eligible for a clinical trial of the drug Opdivo. He's been getting infusions for almost two years. Opdivo activates the immune system, causing it to attack the cancer cells. After several months of treatment, the cancer has shrunk by 90 percent.
Dr. Ben Creelan, a medical oncologist at Moffitt Cancer Center in Tampa, FL says, "It's a real game changer to be able to have a treatment which works for years in some patients."
There are potential side effects including autoimmune disorders, thyroid problems and skin rashes. Vicino suffered from a rare form of double pneumonia. Still for him, the benefits outweighed the risks.
"There now is hope for a lot of people that there wasn't before," Vicino says.
The FDA recently approved Opdivo so it's available to qualified patients. This new drug is approved for both metastatic lung cancer and melanoma.