Gwen Orilio didn’t know how long she had to live after her stage-four lung cancer diagnosis. The disease had already infiltrated her eye, so the 31-year-old didn’t bother opening a retirement account.

Two years ago, Emma Dimery was told her stage 4 colon cancer was incurable. Today, she is healthy and cancer-free — and she says a last-resort clinical trial saved her life. Dimery, who lives in ...