Donna Gustafson had a harder time than usual shaking off the jet lag from her 22-hour journey from Florida to Australia. Two days into her trip, her skin took on the yellow hue of jaundice.<\/p>\n
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Gustafson, who is now 72 and lives in Delray Beach, Florida, went to the emergency room for fluids, thinking she was dehydrated. In a surreal moment, the Australian doctors instead told Gustafson that she had pancreatic cancer<\/a>.<\/p>\n \u201cThey were very adamant about it,\u201d Gustafson said. \u201cThis is absolutely pancreatic cancer.\u201d<\/p>\n She and her husband, Ed, were on the next flight home. Nine days later, Gustafson had surgery to remove the Stage 2 cancer from her pancreas. The day before she was supposed to start chemotherapy, her doctors told her about a clinical trial exploring the use of personalized messenger RNA vaccines for cancer. It was February 2020 \u2014 months before mRNA vaccines for Covid would become one of the world\u2019s hottest commodities. Very soon after, Gustafson was the first person to get one for pancreatic cancer.<\/p>\n \u201cIt was a no-brainer,\u201d Gustafson said of joining the trial. \u201cI knew that statistically, the odds were against me.\u201d<\/p>\n Less than 13% of people diagnosed with pancreatic cancer live for more than five years<\/a>, making it one of the deadliest cancers. There is no routine screening for pancreatic cancer, such as colonoscopy or mammogram, and symptoms typically don\u2019t show up<\/a> until the disease is advanced. Once detected, there are few options for treatment. Only about 20%<\/a> of cases are operable, which is currently required for someone to be eligible to join a pancreatic cancer vaccine trial.<\/p>\n The vaccines work as a type of so-called immunotherapy, harnessing a person\u2019s immune system to fight cancer cells. The goal is not to eliminate existing tumors, but instead to stamp out lingering, undetected cancer cells, and later any new cells that form before they can cause a recurrence.<\/p>\n Patients still have surgery to remove tumors. After that, the mRNA vaccines are personalized for each individual using genetic material taken from their unique tumor cells. In the clinical trial, after getting the vaccine, the patients also received chemotherapy, which is standard post-op treatment for operable pancreatic cancer.<\/p>\n Traditional immunotherapies can be very effective, but they only work in about 20% of all cancers, leaving the majority of cancers without immune-based treatments, said Dr. Vinod Balachandran, director of the Olayan Center for Cancer Vaccines at Memorial Sloan Kettering Cancer Center in New York City, who is leading the trial Gustafson joined.<\/p>\n More on advances in cancer treatment<\/p>\n Pancreatic cancer is the poster child for these difficult-to-treat cancers, Balachandran said, and experts have long believed that people with pancreatic cancer could not generate an immune response against tumors. But after nine doses of the personalized vaccine, Gustafson is one of eight people in the 16-person Phase 1 trial who did just that, producing an army of immune cells called T cells that seek out and destroy tumor cells.<\/p>\n \u201cThis is one of the hardest cancers to generate any immune response, let alone such a potent one,\u201d Balachandran said.<\/p>\n Balachandran and his team published the results of the Phase 1 clinical trial<\/a> last year. At the time, the patients, all of whom had early-stage disease before they joined the trial<\/a>, had only been tracked for just over three years, and it was unclear whether the immune response would last and lead to the patients living longer, he said. New data collected during the trial\u2019s six-year follow-up period shows that it may. Those findings will be presented Monday at the American Association for Cancer Research\u2019s annual meeting in San Diego.<\/p>\n Six years after treatment, Gustafson and six others who responded to the treatment are still alive, along with two of the eight people who did not respond. Two of the responders, including the one who died, had a cancer recurrence; Gustafson\u2019s cancer has not come back.<\/p>\n \u201cThe most important finding here is that the people who mount a response to the vaccine live longer than those who do not,\u201d said Dr. William Freed-Pastor, a physician-scientist at Dana-Farber Cancer Institute, who was not involved with the trial. He cautioned, however, that the results come from a very small group of patients. More research is still needed.<\/p>\n Balachandran has already launched a larger Phase 2 clinical trial on the vaccine. He and his team are also digging into the specifics of what appears to be happening in the immune system.<\/p>\n Their latest findings detail how two important types of T cells likely work in tandem to create a durable immune response, which is paramount for long-term survival. Early on, the team was able to see that the people who responded to the vaccines made a type of T cell called a \u201ckiller T cell.\u201d These are the immune cells that actually attack cancer. The follow-up research found that the longevity of these immune cells appeared to be bolstered by \u201chelper T cells\u201d that the vaccines also appeared to prompt.<\/p>\n \u201cThe assumption is that for an optimal cancer vaccine response, you would want to make both,\u201d Balachandran said.<\/p>\n Shifting the research <\/p>\n Earlier research tested mRNA vaccines to treat people with advanced cancer, with disappointing results, \u201cso we thought we didn\u2019t have a vaccine that would work,\u201d said Dr. Robert Vonderheide, the president-elect of the American Association for Cancer Research and director of the Abramson Cancer Center at the University of Pennsylvania.<\/p>\n In reality, newer research like this Phase 1 trial suggests the immunotherapy may work in less advanced cancer.<\/p>\n \u201cIt\u2019s only when we shifted our mindset that we started to see that vaccines can work in some patients,\u201d said Vonderheide, who was not involved with the trial. \u201cNow that we\u2019re getting into the mechanisms of how these work, we might be able to go back and see how we could make them work in people with more advanced cancer.\u201d<\/p>\n The results are promising but early, he cautioned. There is always a subgroup of people diagnosed with pancreatic cancer who survive longer than five years, which is an important thing to keep in mind with any novel therapy, Vonderheide said.<\/p>\n \u201cThere could be another factor underlying why some patients mount a response that could be the reason they are also surviving,\u201d Freed-Pastor said.<\/p>\n![\"Donna](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/04\/260416-Donna-Gustafson-ew-128p-96c821.jpg\")
Donna Gustafson was diagnosed with pancreatic cancer in 2019. Last year, she hiked Mt. Etna in Italy last year to celebrate her 50th wedding anniversary. Courtesy Donna Gustafson<\/p>\n