(CBS NEWS) -- Ken Shefveland's body was swollen with cancer, treatment after treatment failing until doctors gambled on a radical approach: They removed some of his immune cells, engineered them into cancer assassins and unleashed them into his bloodstream.
Immune therapy is the hottest trend in cancer care and this is its next frontier — creating "living drugs" that grow inside the body into an army that seeks and destroys tumors.
Looking in the mirror, Shefveland saw "the cancer was just melting away." A month later doctors at the Fred Hutchinson Cancer Research Center couldn't find any signs of lymphoma in the Vancouver, Washington, man's body.
"Today I find out I'm in full remission — how wonderful is that?" said Shefveland with a wide grin, giving his physician a quick embrace.
This experimental therapy marks an entirely new way to treat cancer — if scientists can make it work, safely. Early-stage studies are stirring hope as one-time infusions of supercharged immune cells help a remarkable number of patients with intractable leukemia or lymphoma.
"It shows the unbelievable power of your immune system," said Dr. David Maloney, Fred Hutch's medical director for cellular immunotherapy who treated Shefveland with a type called CAR-T cells.
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