More people are surviving a cancer diagnosis today than in the 1970s, according to a report released earlier this year by government agencies and cancer groups. That's the good news facing former Vice President Joe Biden, who's speaking with Mike Allen at an Axios event in Philadelphia today, as he continues his work to speed the progress of cancer research.

But the survival rates are still low for several kinds — including brain cancers like the type that killed his son, Beau Biden.

What's next: Immunotherapies are one promising area of cancer treatment, but there are questions about why checkpoint inhibitors (one class of immunotherapeutic drugs) work in some patients but not others. These treatments, and others known as CAR T-cell therapies that involve changing a patient's own immune cells so they will attack cancerous cells, can also cause serious side effects that researchers are racing to understand.

Dr. Elizabeth Jaffee of Johns Hopkins University, president-elect of the American Association for Cancer Research, says these are the most likely advances in immunotherapy to watch over the next few years:

• Developing "accelerator" therapies to help the immune system activate more quickly.
• Activating T-cells that have never been activated before by targeting monocytes, a type of white blood cell.
• Inhibiting molecules formed when T-cells metabolize so the immune cells can better respond to cancerous ones.

Keep in mind: For breast, prostate and a handful of other cancers, increased screening and early detection may have improved survival rates while masking only minor gains in longevity. Prevention is how we've made the most headway in decreasing actual death rates from cancer — with fewer people smoking, for example — and where more progress can be made.