SEATTLE — The next big advance in cancer treatment could be a vaccine.

After decades of limited success, scientists say research has reached a turning point, with many predicting more vaccines will be out in five years.

These aren’t traditional vaccines that prevent disease, but shots to shrink tumors and stop cancer from coming back. Targets for these experimental treatments include breast and lung cancer, with gains reported this year for deadly skin cancer melanoma and pancreatic cancer.

“We’re getting something to work. Now we need to get it to work better,” said Dr. James Gulley, who helps lead a center at the National Cancer Institute that develops immune therapies, including cancer treatment vaccines.

More than ever, scientists understand how cancer hides from the body’s immune system. Cancer vaccines, like other immunotherapies, boost the immune system to find and kill cancer cells. And some new ones use mRNA, which was developed for cancer but first used for COVID-19 vaccines.

For a vaccine to work, it needs to teach the immune system’s T cells to recognize cancer as dangerous, said Dr. Nora Disis of UW Medicine’s Cancer Vaccine Institute in Seattle. Once trained, T cells can travel anywhere in the body to hunt down danger.

“If you saw an activated T cell, it almost has feet,” she said. “You can see it crawling through the blood vessel to get out into the tissues.”

Patient volunteers are crucial to the research.

Kathleen Jade, 50, learned she had breast cancer in late February, just weeks before she and her husband were to depart Seattle for an around-the-world adventure. Instead of sailing their 46-foot boat, Shadowfax, through the Great Lakes toward the St. Lawrence Seaway, she was sitting on a hospital bed awaiting her third dose of an experimental vaccine. She’s getting the vaccine to see if it will shrink her tumor before surgery.

“Even if that chance is a little bit, I felt like it’s worth it,” said Jade, who is also getting standard treatment.

Progress on treatment vaccines has been challenging. The first, Provenge, was approved in the U.S. in 2010 to treat prostate cancer that had spread. It requires processing a patient’s own immune cells in a lab and giving them back through IV. There are also treatment vaccines for early bladder cancer and advanced melanoma.

]]>