Glioblastoma

Glioblastoma, previously known as glioblastoma multiforme, is a type of cancer that develops in the brain or spinal cord. These tumors originate in glial cells, which are responsible for protecting, nourishing, and supporting neurons.

Although they are sometimes confused, glioma and glioblastoma are not the same. While a glioma refers to any tumor that forms in glial cells, glioblastoma is a type of glioma characterized by rapid growth and a high degree of malignancy. In short, glioblastoma is a grade IV glioma.

Glioblastomas can be classified into two types according to their characteristics:

• Low-grade glioblastomas (grades I and II): the cellular appearance is almost normal. They grow slowly and are less aggressive.
• High-grade glioblastomas (grades III and IV): tumors grow very rapidly and are highly aggressive. Their cellular composition differs significantly from that of healthy cells.

There are two types of glioblastomas depending on their evolution:

• Primary glioblastoma: the most common form (approximately 90%). It develops rapidly and arises de novo, meaning without a prior smaller and less malignant glioma.
• Secondary glioblastoma: develops from a slow-growing tumor. These are less aggressive than primary glioblastomas.

The prognosis of glioblastoma is generally unfavorable, although it varies widely depending on patient characteristics and tumor malignancy grade. The five-year survival rate typically ranges between 20% and 24%, as this cancer is highly resistant to therapy. Current treatments can slow tumor growth and reduce symptoms, but the average life expectancy is between 12 and 15 months from diagnosis. At present, multiple scientific studies are underway to identify more effective therapies for glioblastoma.

Symptoms

Common symptoms of glioblastoma include:

• Headache (more intense in the morning).
• Drowsiness.
• Nausea and vomiting.
• Seizures.
• Cognitive impairment.
• Memory loss.
• Balance or coordination problems.
• Irritability, personality changes.
• Hemorrhage.
• Reduced tactile sensitivity.
• Depending on tumor location, specific symptoms such as:
  • Speech difficulties.
  • Unilateral loss of strength.
  • Visual field impairment.

Causes

The exact causes of glioblastoma formation are unknown.

Cancer, in general, develops when cellular DNA undergoes changes, causing cancer cells to grow faster than normal and survive longer than healthy cells. As a result, they accumulate and form tissue masses known as tumors.

Risk factors

Although the exact causes of glioblastoma are not known, studies have identified several factors commonly present in patients and therefore considered to increase risk:

• Age: more common between 55 and 75 years; however, secondary glioblastomas often occur in younger patients.
• Degenerative brain diseases.
• Exposure to radiation, typically radiotherapy to the head for other conditions.
• Weakened immune system.
• Family history of:
• Glioblastoma.
• Neurofibromatosis type 1 or type 2.
• Tuberous sclerosis.
• Von Hippel–Lindau syndrome.
• Li-Fraumeni syndrome.
• Turcot syndrome.

Complications

Complications associated with glioblastoma are often severe. The most significant include:

• Cognitive damage: confusion, memory impairment, difficulty concentrating, language disturbances, or impaired reasoning.
• Psychological damage: personality changes, anxiety, or depression.
• Edema: inflammation and fluid accumulation in brain tissue.
• Hydrocephalus: accumulation of cerebrospinal fluid in the brain ventricles.
• Seizures, loss of consciousness, or sensory disturbances.
• Death.

Prevention

Glioblastoma cannot be prevented. Nevertheless, adopting a healthy lifestyle and avoiding exposure to ionizing radiation are recommended to reduce risk.

Which specialist treats glioblastoma?

Treatment of glioblastoma requires collaboration among specialists in neurology, neurosurgery, medical oncology, and radiation oncology.