What is glioblastoma? Inside Michael Bolton’s cancer — and 5 signs to watch for

That stinks!

A 57-year-old UK father of four recently made headlines when he revealed the bizarre clue that preceded his Stage 4 glioblastoma diagnosis — a “strange sweet caramel smell.”

“We didn’t think much of it,” said Costa Fantis’s 27-year-old son, Antonio. “We definitely didn’t know it was a symptom of something so serious.”

Before two-time Grammy winner Michael Bolton, 72, was diagnosed with glioblastoma in 2023, he experienced confusion, balance issues, nausea and severe headaches.

The tumor, which occurs when supportive cells in the brain grow and divide uncontrollably, is extremely aggressive and deadly. Most patients survive only 14 to 16 months after diagnosis.

“What makes glioblastoma particularly difficult to treat is its highly invasive nature — it spreads microscopic cancer cells deep into surrounding brain tissue, making it impossible to remove completely with surgery,” Dr. Joseph Georges, a neurosurgeon based in Phoenix, told The Post.

Georges shares five early glioblastoma warning signs — and how a specialized cell therapy may prolong patient lives.

What are the risk factors for glioblastoma?

About 14,500 new glioblastoma cases are diagnosed annually in the US.

The average age of diagnosis is around 64 — the cancer tends to affect adults 45 to 70 years old.

Exposure to ionizing radiation as part of radiation therapy for other cancers and certain genetic disorders, such as Turcot syndrome and Lynch syndrome, can increase glioblastoma risk.

However, most cases “occur spontaneously in individuals without risk factors,” said Georges, an assistant professor of neurosurgery at the University of Arizona College of Medicine and Banner University Medical Center-Phoenix.

What are the symptoms?

Symptoms depend on the tumor’s location within the skull.

They may include headaches, confusion, seizures, speech difficulty or weakness on one side of the body, Georges said.

In Bolton’s case, his daughters noticed unusual behavior during a family bowling night in the fall of 2023.

He had bowled out of turn and fallen out of his chair. He was diagnosed a few weeks later.

Fantis’s tumor appears to have developed in the temporal lobe, which plays a crucial role in processing smells.

How is it diagnosed?

The tumor can be identified with a CT scan or MRI, and the diagnosis confirmed with a tissue biopsy.

“Several factors influence how long a person might live with glioblastoma,” Georges said, “including their overall health, neurological function at diagnosis, age and how well they respond to treatments such as surgery, radiation and chemotherapy.”

The molecular characteristics of the tumor — like whether it has mutations — can affect the prognosis.

How is glioblastoma treated?

Metastatic brain tumors — tumors that start elsewhere in the body and spread to the brain — tend to form masses that are better defined than glioblastomas and that can be surgically removed more easily.

“Glioblastoma’s diffuse growth pattern, genetic complexity and resistance to standard treatments make it one of the most challenging brain tumors to treat,” Georges noted.

“Complete removal is usually not achievable due to the tumor’s infiltrative nature.”

Surgery is often followed by radiation therapy to eliminate residual tumor cells and delay progression and chemotherapy to enhance the effectiveness of radiation.

Despite this multi-pronged strategy, Georges admitted that “glioblastoma generally has a poor prognosis due to its aggressive biology and treatment resistance.”

How can DOC1021 help?

Georges said he has seen better outcomes with an individualized approach.

He was the principal investigator of a Phase 1 clinical trial evaluating Dubodencel, also known as DOC1021, which harnesses the power of the patient’s special immune cells, called dendritic cells.

The cells are exposed to the unique antigens of the tumor outside the body.

“Once trained, the cells are multiplied and then returned to the patient, where they help the immune system launch a targeted attack against the cancer,” Georges said.

“Because this approach uses the patient’s own immune cells and doesn’t require genetic modification, it offers a highly personalized and comprehensive way to address the complexity and variability of glioblastoma.”

The Food and Drug Administration granted fast-track designation to DOC1021, developed by Diakonos Oncology, to treat glioblastoma and pancreatic cancer.

Some patients in the DOC1021 Phase 1 trial are approaching 24 to 36 months of survival.

“Early clinical results from the trial showed a 12-month overall survival rate of 88%, markedly higher than the approximately 60% typically seen with standard of care,” Georges said.

New Jersey resident Pamela Goldberger, 65, underwent brain surgery, six weeks of chemotherapy and radiation, six weeks of the cell therapy and a year of chemo maintenance as part of the DOC1021 Phase 1 trial. Now, she is back to playing tennis several times a week 2½ years after her diagnosis.

“I’m living my best life right now, and I’m not restricted by not being able to do anything that I would want to do,” she recently told Fox News Digital.

The Phase 2 clinical trial is underway — it’s expected to be available at 20 US sites.