Research published today in the journal Nature concludes a tetanus booster given before immunotherapy treatment can significantly extend the lives of people with brain tumors.

While glioblastoma brain tumors generally prove deadly a little more than one year after diagnosis, six volunteers in a clinical trial who received the booster treatment survived much longer. Half of the patients lived five years or longer.

The trial involved 12 patients. Half received a tetanus shot the day before immunotherapy treatments and half did not. One volunteer is still alive today, almost nine years after her cancer diagnosis.

Tetanus Shot

“At this point and throughout the years, she maintains a great quality of life,” said researcher Kristen Batich, a member of the study team led by Dr. John H. Sampson, chief of the Division of Neurosurgery at Duke University Medical Center, in an interview with Healthline. “We are truly excited to witness such a great response like in the case of this patient because glioblastoma is such a fatal tumor that is truly difficult to treat.”

The patients who received only the immunotherapy and not the tetanus booster lived on average 18.5 months. That compares to the usual life span of 12 to 14 months for people diagnosed with a brain tumor.

Adults between the ages of 65 and 79 are most likely to develop brain tumors. Less than 4 percent live as long as five years.

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Dendritic Cells Teach Other Cells to Fight Cancer

Glioblastoma tumors kill quickly because they take advantage of an already suppressed immune system. Batich said such tumor cells “shut off some of their receptors that the immune system needs to recognize as foreign, and even have ways to exhaust the fighting T lymphocytes that kill tumor cells.”

To boost the immune system, the researchers used a vaccine containing dendritic cells for immunotherapy. Immunotheraphy is the name for any cancer treatment that uses a person’s own immune system to attack tumors. Dendritic cells migrate to the lymph nodes and can teach other cells certain tasks — in this case, how to fight glioblastoma.

“Our dendritic cells vaccine is focused on the earlier phase of directing what foreign invader exists and relies on enough of these master activators reaching the lymph nodes, where they act as drill sergeants to train the immune cells about the tumors,” Batich said.

Immunotherapy works well for treating cancer, but the researchers wondered whether the immune system could fight back even harder if they first primed it with a tetanus shot.

Batich describes the tetanus shot as “sounding a siren” to the immune system that more help is coming in the form of immunotherapy and to get ready.

Batich hopes dendritic cell vaccines, along with a tetanus booster, could pack a one-two punch.

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Is Immunotherapy the Key to Killing Cancer?

Combined with previous research by Batich, scientists now understand how to actually get immunotherapy to the cells that need it. The body’s response to one invader — an inactive form of tetanus in the vaccine shot — spurs the body to recruit dendritic cells to fight off other invaders, including cancer cells.

“Because of the limitation in getting enough [dendritic] cells to the lymph nodes when you inject them into the skin,” Batich told Healthline, “we think that something like tetanus, which is a potent yet already available and safe booster, can put the lymph nodes and the immune system on high alert to watch out for the next pathogen, in this case our immunotherapy specific for tumors.”

Immunotherapies are fairly new in the cancer field, but they are showing a lot of promise, especially alongside existing treatments.

“Because using the immune system is a completely different avenue than traditional therapies,” she added, “and because this approach is so specific to tumor cells, we think it would be a great combination to add on top of these traditional therapies.”

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