Flu Shot for Melanoma: Can a 135-Year-Old Cancer Idea Save Lives?

What if one of the most intriguing new cancer treatments turns out to be based on an idea from 1891? Researchers are now testing a flu shot for melanoma. The idea is that the body’s immune system could be trained to recognize and attack malignant tumors. The preliminary results are surprisingly promising. And the story takes us back 135 years to a courageous, controversial cancer surgeon named William Coley, MD.

A Flu Shot for Melanoma? An Unexpected Discovery!

Most people think of influenza vaccines as a way to prevent the flu. But scientists at The Ohio State University Comprehensive Cancer Center are investigating a radically different use for this familiar vaccine. They are injecting it directly into melanoma tumors!

Melanoma is a potentially deadly form of skin cancer. Although new treatments have dramatically improved survival for many patients, advanced melanoma can still be difficult to treat. The researchers wondered whether an ordinary influenza vaccine could help awaken the immune system to attack melanoma cells.

Their findings, presented in the Journal for ImmunoTherapy of Cancer (November 3, 2026), are intriguing.

A Preliminary Trial with Exciting Results:

The study involved 18 patients with stage I, II or III melanoma. All were scheduled to have their tumors removed surgically. Yes, that is a very small number. It is called a phase 1b trial.

First, the patients received an ordinary flu shot in the arm. Then investigators injected an influenza vaccine directly into their tumors on two occasions before surgery.

When pathologists examined the removed tumors, they discovered something remarkable:

• Seven of the 18 patients (39%) showed signs of tumor regression.
• Three patients had complete pathological responses. No viable melanoma cells were found in the examined surgical specimens.
• Nearly 80% of tumor samples showed substantial infiltration by immune cells called lymphocytes.
• There were no dose-limiting toxicities reported.

The researchers also detected changes in immune-system activity suggesting that the vaccine had stimulated the body’s defenses against the cancer.

Caveats Regarding a Flu Shot for Melanoma

The study was small and lacked a control group. It was designed primarily to evaluate safety and immune responses, not to prove that flu vaccine injections cure melanoma or prolong survival.

Nevertheless, the findings raise a fascinating question: Could a familiar, relatively inexpensive vaccine someday become a useful tool against a deadly cancer?

The Forgotten Cancer Surgeon Who Was 135 Years Ahead of His Time

To understand why this new research is so intriguing to us, we need to travel back to 1891. Dr. William Coley was a young New York surgeon who had become frustrated by the limitations of cancer treatment. At the time, surgery was often the only option. Even aggressive operations frequently failed. They are still only partially effective today.

One particularly tragic case involved a young woman with sarcoma who died despite having her arm amputated. Coley began searching through old medical records, hoping to discover something that might help future patients.

He came across reports of cancer patients whose tumors had mysteriously disappeared or shrunk after severe bacterial infections accompanied by high fevers. He asked himself whether the infection could have somehow triggered the immune system to attack the malignancy. It was a startling possibility.

Coley began experimenting with deliberately induced infections in patients with otherwise untreatable cancers like sarcomas. His early efforts were dangerous and sometimes fatal. But some patients experienced remarkable tumor regression.

Eventually, he developed a preparation made from heat-killed bacteria that became known as Coley’s toxin, or Coley’s toxins. During the following decades, Coley treated hundreds of cancer patients, many with sarcoma. Some experienced prolonged remissions. His treatment was unpredictable, however, and the historical evidence does not meet today’s standards for establishing safety and effectiveness.

As radiation therapy and later chemotherapy became more widely available, Coley’s approach gradually faded into medical history. But the idea behind his treatment never completely disappeared. Could the question Dr. Coley was asking lead to the breakthrough we have been seeking for centuries?

Could stimulating the immune system help the body fight cancer?

Today, William Coley is often called the father of cancer immunotherapy. You can learn more about his amazing research and treatment in an article titled “The toxins of William B. Coley and the treatment of bone and soft-tissue sarcomas.” You can find the full article in the Iowa Orthopaedic Journal (2006). The full-text article is available for free!

Should you wish to listen to a radio show we conducted several years ago, here is a link to Show 1151:

What Was the First Immunotherapy for Cancer?
Dr. William Coley developed the first immunotherapy for cancer more than 100 years ago. How did this bacterial toxin work to overpower tumors?

How Could a Flu Shot for Melanoma Stimulate the Immune System?

Cancer cells can be remarkably good at avoiding detection by the immune system. Some tumors create an environment that discourages immune cells from entering or attacking them. Scientists sometimes call these cold tumors.

Immunotherapy attempts to change that situation by helping the body’s defenses recognize and destroy malignant cells. One strategy is to turn a cold tumor into a hot tumor, filled with activated immune cells.

That is where the influenza vaccine comes in. When researchers inject the vaccine directly into a melanoma tumor, they hope to create a localized immune response that attracts cancer-fighting cells. This possibility is not entirely new.

In 2020, investigators published a fascinating study in the Proceedings of the National Academy of Sciences (Jan. 14, 2020). They found that injecting seasonal influenza vaccine directly into tumors in mice could slow tumor growth and make resistant tumors more responsive to certain immunotherapy drugs. The researchers suggested that the vaccine could transform immunologically cold tumors into hot ones.

The new human study takes this fascinating idea one step further. Instead of relying solely on animal experiments, investigators have now demonstrated immune-system changes and evidence of tumor regression in patients with melanoma. That does not establish that the vaccine caused every observed regression, but it provides a good reason for further research.

Can a Flu Shot for Melanoma Make Cancer Immunotherapy More Affordable?

One of the biggest challenges facing modern cancer treatment is cost. Some immunotherapy medications can cost hundreds of thousands of dollars for a course of treatment. Even when insurance covers much of the expense, the financial burden on patients and the healthcare system can be enormous.

What if a relatively inexpensive vaccine, such as a flu shot, could improve the effectiveness of these sophisticated treatments? That is one of the exciting possibilities raised by this research. Investigators are continuing to study influenza vaccine injections in patients with advanced melanoma who are also receiving immune checkpoint inhibitors. These drugs are among the most important advances in cancer immunotherapy. They help remove some of the molecular brakes that prevent immune cells from attacking cancer.

The hope is that injecting influenza vaccine into a tumor might make the cancer more vulnerable to these powerful medicines. Of course, an inexpensive vaccine does not automatically translate into inexpensive cancer treatment. Delivering injections directly into tumors, monitoring patients and combining vaccines with other therapies can still be costly. But compared to most of our current immunotherapies, the flu vaccine itself is remarkably inexpensive.

There is a critical distinction: An ordinary flu shot in the arm has not been shown to treat melanoma. The experimental treatment involves injecting vaccine directly into a tumor under carefully controlled research conditions.

Nor has this approach been shown to cure sarcoma, the cancer that William Coley treated. Still, researchers may be rediscovering an important principle that Coley recognized more than a century ago: Sometimes the immune system needs a wake-up call.

What Can William Coley’s Forgotten Cancer Treatment Teach Us Today?

Here is where this story becomes especially interesting to us at The People’s Pharmacy. Several years ago, we devoted a number of radio programs to the history of Coley’s toxin and the emerging science of cancer immunotherapy.

Show 1151: What Was the First Immunotherapy for Cancer?

Our guests offered remarkable insights into how infections, inflammation and the immune system might influence the course of cancer.

Don MacAdam, former head of MBVax Bioscience and author of The Reinvention of Coley’s Toxins, described efforts to revive Coley’s historic approach to cancer treatment.

Sharon S. Evans, PhD, an immunologist and professor of oncology at Roswell Park Comprehensive Cancer Center, explained the complex relationship between inflammation, fever and the immune system’s response to cancer.

Filip Janku, MD, PhD, a cancer researcher at MD Anderson Cancer Center, discussed research involving the injection of bacterial spores directly into tumors.

These conversations explore a provocative possibility: Could carefully controlled stimulation of the immune system help physicians treat cancers that resist conventional therapies?

We invite you to listen to this fascinating program. It provides historical context for the latest melanoma research and offers a glimpse into the future of cancer immunotherapy.

Listen to Show 1151: What Was the First Immunotherapy for Cancer?

The extended podcast includes additional discussion about efforts to revive Coley’s treatment and research involving bacteria as potential cancer-fighting agents.

The People’s Pharmacy Perspective: Can an Old Idea Transform Cancer Treatment?

We have long been fascinated by medical discoveries that challenge conventional thinking. William Coley could not have explained the intricate workings of T cells, cytokines or immune checkpoints. Those concepts did not exist in his day.

But he observed something important: Under certain circumstances, provoking an immune response appeared to help some patients overcome cancers that seemed hopeless. Sarcomas are still very challenging today. More than a century later, researchers have the scientific tools to investigate his basic insight with greater precision and safety.

The new melanoma study is small. It is preliminary. And it does not prove that influenza vaccine injections will prolong life or prevent cancer from returning. But what if the next breakthrough in cancer immunotherapy comes not from an extraordinarily expensive new drug, but from finding a surprising new use for an old vaccine?

That possibility deserves serious scientific investigation. Sometimes the most revolutionary ideas in medicine turn out to have very deep roots. We only wish modern medicine would pay more attention to Dr. Coley’s amazing research.