What is glioblastoma?

Glioblastoma is the most frequent, most aggressive and most deadly malignant brain tumor, accounting for approximately half of all primary brain tumors and affecting more than 2 percent of Americans today.

The National Cancer Institute reported more than 22,000 new diagnoses and more than 15,000 resulting deaths in 2015. More than 12,000 new glioblastoma cases are estimated in 2017.

Glioblastoma, also known as glioblastoma multiforme or GBM, generally occurs in the cerebral hemispheres of the brain, but can occur anywhere in the brain or spinal cord. It is the most invasive type of glial tumors, growing rapidly, resisting treatment and spreading to nearby brain tissue. Of all brain and spinal cord tumors, glioblastoma has the shortest life expectancy (less than 1 year in most cases) and lowest survival rate (only 5 percent over three years).

Glioblastomas can cause headaches, nausea, speech and vision changes, personality changes, coordination problems and seizures. Symptoms may emerge suddenly or develop gradually.

The cause of glioblastoma is unknown but several genetic and environmental risk factors have been identified. While glioblastomas affect people with no family history of tumors, genetic disease risk factors include Turcot syndrome, a condition characterized by abnormal cells and polyps, and neurofibromatosis, a tumor-causing genetic disorder. Potential environmental risk factors include exposure to chemicals; drinking alcohol; using tobacco; and eating or not eating certain foods.

There is no known cure.

Surgical, drug and radiation therapies, alone or in combination, simply help ease symptoms.

Brain tumors like glioblastomas have the highest per-patient initial cost of care for any cancer group — more than $100,000.

Who’s most affected by glioblastoma?

Glioblastoma manifests in people of all ages, but it primarily affects adults between ages 45 and 75. Men, median age 59, account for approximately 55 percent of glioblastoma deaths.

The single most important factor related to developing and surviving malignant brain tumors is age. The prognosis is most favorable for people under age 40.

Among adolescents and young adults age 15 to 39, tumors in the brain and central nervous system are the third most common cancer and the third leading cause of cancer deaths in the age group. Glioblastoma accounts for only 3 percent of childhood brain tumors.

How can cannabis assist glioblastoma therapy?

Until recently, therapy options for high-grade glioblastoma tumors have been limited to surgery, chemotherapy and radiation.

In the past 30 years, the FDA has approved four drugs for brain tumor chemotherapy: Temozolomide, Carmustine, Bevacizumab and Everolimus. All have performed poorly in stopping cell proliferation and eliminating tumor mass.

Today, studies show that cannabis is capable of killing brain cancer cells and scientists are finding that cannabis, when used in conjunction with other forms of cancer therapy, is capable of shrinking aggressive glioblastoma tumors.

A 2014 study at St. George’s University of London found THC and CBD cannabinoids to be highly efficient at destroying glioma cells. Additionally, researchers found that when THC and CBD were used together, researchers could use less of each compound and still achieve the same effects. Moreover, chemotherapy and radiotherapy make cancer cells much more sensitive to THC and CBD.

According to a 2014 study published in the Journal of Biological Chemistry, THC acts on cannabinoid cell receptors to inhibit the interactions between them, thus decreasing the risk that cancer will form or interrupting cancer that is already growing.

Researchers believe cannabinoids may prepare neural pathways for radiotherapy and help kill diseased cells, causing them to self-absorb while producing no negative effects in healthy cell tissue surrounding the glial cells. Conversely, chemotherapy drugs kill diseased cells but release dead cells’ toxic remains into the bloodstream, potentially affecting other parts of the body.

Researchers also believe cannabinoids’ anti-tumor effects can possibly even protect healthy cells from damage and prevent cancers in the first place.

How does cannabis complement traditional therapies?

In addition to showing promise in shrinking aggressive glioblastoma tumors when used in conjunction with traditional cancer therapies, cannabis may relieve the side effects of chemotherapy and radiation, including headaches, nausea, vomiting, diarrhea, constipation, loss of appetite, insomnia and mood disorders.

Cannabis could potentially replace the two synthetic cannabis pharmaceuticals that have been specifically approved by the FDA for relieving nausea and vomiting associated with cancer chemotherapy: dronabinol (brand name: Marinol) and cesamet (brand name: Nabilone). Sativex, a THC extract spray, has not been approved for use in the United States.

What are effective consumption methods for glioblastoma cannabis therapy?

Most chemotherapy drugs are administered intravenously. Some chemotherapy drugs are administered via pill or capsule.

Glioblastoma cannabis therapies are administered orally via pill or capsule; sublingually via cannabis oil extracts and sprays; or inhaled via vaporizer or smoking.

Given the large amounts of cannabinoids administered in some protocols, sublingual consumption of cannabis extract suspended in a food-grade oil is one of the most popular methods of ingestion.

What are effective dosages and ratios for glioblastoma cannabis therapy?

While there is no statistical data due to research restrictions, anecdotal reports and peer-reviewed studies suggest a fully balanced 1:1 ratio of both CBD and THC pass through the blood brain barrier easier than either cannabinoid alone or in other ratios.

Dosages vary by protocol and patient. Some protocols use 10 to 15 mg of THC/CBD per day while others can call for up to 600 mg per day.