Walking Dead Star Kelley Mack Dies at 33 from Rare Central Nervous System Glioma – What to Know

Kelley Mack, best known for her role as Addy in The Walking Dead, has tragically passed away at age 33 after a courageous battle with central nervous system glioma. The actress, also seen in 9-1-1, Chicago Med, and Spider-Man: Into the Spider-Verse, died peacefully surrounded by family after months of aggressive treatment for this rare and aggressive cancer.

Her diagnosis came after experiencing persistent pain in her back and leg, initially mistaken for a spinal injury. But further tests revealed the true cause: a tumor on her spinal cord—part of a high-grade glioma affecting the central nervous system. Despite undergoing surgery, radiation, and chemotherapy, Mack’s condition rapidly declined due to the nature of the disease.

What Is Central Nervous System Glioma?

Central nervous system gliomas are a type of tumor that forms in the glial cells—supportive cells that surround neurons in the brain and spinal cord. These tumors can range from slow-growing, benign forms to highly aggressive malignant types.

The most serious forms, such as diffuse midline glioma, are typically classified as grade IV tumors. These are fast-spreading, inoperable in many cases, and resistant to standard treatments. Central nervous system gliomas can occur in both adults and children, although they are more common in younger individuals and often present differently depending on the tumor’s location.

Signs and Symptoms of Glioma: What to Watch For

The symptoms of central nervous system glioma vary depending on where the tumor is located, but they often include:

• Persistent headaches

• Back or neck pain with neurological signs

• Vision problems or slurred speech

• Muscle weakness or numbness in limbs

• Behavioral changes

• Seizures or sudden loss of coordination

In Kelley Mack’s case, pain radiating through her leg and impaired mobility were early signs. These red flags are frequently dismissed as minor injuries or stress-related, especially in younger adults, leading to delayed diagnoses.

How Is CNS Glioma Diagnosed?

Diagnosing glioma begins with a thorough neurological examination, often followed by imaging such as MRI or CT scans. If a tumor is detected, a biopsy is typically required to determine the tumor’s grade and specific genetic markers.

Some gliomas, particularly diffuse midline gliomas, are marked by specific genetic mutations (like H3 K27M), which influence prognosis and treatment decisions. Early detection is critical, but many patients are diagnosed only after symptoms become severe or disabling.

Treatment Options for Glioma: What’s Available Today?

Treatment for central nervous system glioma depends on the tumor’s type, location, and grade. Options may include:

• Surgery: If accessible, tumors may be partially or fully removed.

• Radiation therapy: Often used when surgery is not viable or to kill remaining cancer cells post-surgery.

• Proton beam therapy: A precise form of radiation especially beneficial for tumors near critical brain structures.

• Chemotherapy: Common drugs like temozolomide are used to slow tumor growth.

• Experimental therapies: Trials are exploring nanotechnology, gene editing, and personalized immunotherapy for treatment-resistant gliomas.

Unfortunately, high-grade gliomas like those affecting Mack are often incurable. These tumors tend to recur and resist treatment, leaving doctors with limited tools to prolong survival.

Why This Matters: Early Detection and Awareness

Kelley Mack’s tragic experience highlights a broader issue: gliomas are often misunderstood and misdiagnosed, especially in young adults. Symptoms may resemble more common ailments such as sciatica, migraines, or muscular injuries. When pain persists or worsens, it’s crucial to push for medical imaging and evaluation by specialists.

Public awareness, research funding, and innovation in brain cancer treatment remain vital. Gliomas, especially aggressive types affecting the brainstem or spinal cord, are a major frontier in cancer research. Early detection, accurate diagnosis, and access to advanced care can significantly affect outcomes.

Kelley Mack’s story is a reminder that even rare diseases can strike unexpectedly—and that vigilance, awareness, and science are our best defense.

You Must Know (FAQs)

What is central nervous system glioma?
It is a tumor originating from glial cells in the brain or spinal cord. These can range from slow-growing benign tumors to aggressive, life-threatening cancers.

What symptoms should I look for?
Headaches, back or neck pain, numbness, vision problems, behavioral changes, and seizures may be signs. Persistent or unexplained symptoms should always be evaluated by a medical professional.

Is central nervous system glioma curable?
Low-grade gliomas may be treatable or manageable with surgery and therapy. However, high-grade types like diffuse midline gliomas are often fatal and difficult to control.

Who is at risk of developing glioma?
Gliomas can affect anyone but are more common in children and younger adults. Some genetic conditions, like neurofibromatosis, increase risk.

What treatments are available for CNS glioma?
Standard treatments include surgery, chemotherapy, and radiation. New approaches like proton therapy and targeted drug delivery are in clinical trials for advanced cases.

Can young people get CNS gliomas?
Yes. While more common in children, gliomas also affect people in their 20s and 30s. Kelley Mack’s case illustrates that age is not a guarantee of safety.