Pancreatic cancer is a tough disease to deal with. It can be quiet for a time until it has spread and become advanced. Even when doctors are able to remove the tumor with surgery it often comes back. Many people who have cancer only live for a year or two after they are diagnosed. This is why any improvement that is achieved in the treatment of this disease seems extremely significant.
Doctors at Memorial Sloan Kettering Cancer Center recently provided some updates on a study of a new pancreatic cancer treatment. This treatment uses the body’s defense system in a new way. The results of the study, which were presented at a cancer meeting show that some patients who received a custom-made vaccine after surgery are doing well years later. Not every person can be cured by this and additional research is required. The results provide hope to people who have pancreatic cancer and their families to discuss.
And why do pancreatic cancer recur even after surgery?
In cases where the surgeons are removing the tumor small cancer cells may still be lurking in the body. The common therapies, such as chemotherapy attempt to locate and kill these cells. They do not always work. For people the cancer comes back within the first couple of years. This happens because pancreatic cancer cells are able to change and hide from the system. The body’s natural defenses get confused. Do not see the cancer cells as a threat. This new treatment tries to fix this problem. The researchers have merely provided drugs that kill the cells to condition the immune system to consider the cancer a foreign invader.
But how does a personalized mRNA vaccine work?
It is comparable to providing the system with a picture of the cancer cells so that it can identify them and destroy them. Doctors who perform surgery send out a fragment of the removed tumor to a laboratory. Scientists study it to find the markers, called neoantigens that are only on the cancer cells. They then build a molecule that carries instructions for the body to make copies of these markers. When the vaccine is given the body reads the instructions. Creates immune cells that can spot the cancer cells. The whole process is custom-made for each person, which’s why it is called a personalised mRNA vaccine. In the study patients also received another medicine that helps the immune system work better plus the usual chemotherapy.
Who joined this study?
The study included 16 adults with stage pancreatic cancer who had just had successful surgery. They all started treatment after the operation. First they received a medicine that helps the system then the personalised vaccine and finally more chemotherapy. The goal was to give the body every tool to fight the cancer before any hidden cancer cells could grow back. One of the people to try this treatment was Donna Gustafson at the end of 2019.
And what transpired in six years?
The researchers checked on the patients again six years later. They found out that half of the patients were responding to the vaccine. The cells generated by their bodies continued to work even after the treatment was completed. Of these eight patients seven are still alive today between four and six years after their surgery. One patient did see the cancer return. Later passed away. In the group of patients who did not respond as well to the vaccine only two are still alive and they did not live as long. The study also showed that the immune cells stayed active in the blood for years, which’s very important.
Why is the staying power of these cells such a big deal?
Normally, the system’s response to a treatment can fade over time.. In the patients who responded well to the vaccine the immune cells kept working like a security team that never stopped. They became memory cells that patrolled the body and stayed ready to attack the cancer. Some of these cells are still working seven years or more after the treatment. This is quite significant since pancreatic cancer tends to recur after 3 years. The fact that it has cells even years later may be the reason why most of the patients who were treated successfully with the vaccine have survived.
Does that imply that this vaccine is effective in all patients?
No it does not! The study had only a response to the vaccine by half of the patients. The other half did not. The results that they achieved resembled those that physicians normally observe in conventional care. Scientists are yet to establish precisely why certain patients are more responsive as compared to others. It could be because of differences in the tumour or in each person’s system. The good news is that the vaccine was safe with mild side effects. No one had to stop treatment because of problems.
What are the next steps? What should families keep in mind?
Larger studies are already underway to test the vaccine in patients and compare it to standard treatment. These studies will take a few years to finish but they will help us understand whether the results of the small study will hold up. In the meantime doctors are being careful not to raise hopes. Pancreatic cancer is still a disease and this vaccine is not yet available outside of research studies. When you have cancer or a loved one, the worst thing that you can do is to discuss everything openly to a specialist to find out what the current options are and any trials that may be offered.
A silent form of hope:
The stories such as that of Donna Gustafson are a wake-up call that science is a step by step process. Now, she is alive while spending time with her family more than 6 years after she was diagnosed. Her vaccine-trained immune cells continue to work towards maintaining her health.
Nobody is making any miracles. Such treatment demonstrates that it can be taught to the body to retaliate in a smarter and more enduring manner. This message may be a breath of fresh air to people living with cancer. Researchers, patients and families are closely following the studies with the hope that the initial promise will become something that will enable many more people to live fuller lives.
REFERENCE LINKS:
https://pmc.ncbi.nlm.nih.gov/articles/PMC11879674/
https://honcology.com/blog/advances-in-personalized-vaccine-development-for-pancreatic-cancer