The mainstream, standard-of-care treatment for brain tumors consists of some combination of resection (surgery to remove the tumor), radiation (destroying cancer cells with a precision-shaped beam of energy), and chemotherapy (the use of powerful drugs that are toxic to tumor cells. These are all effective to some degree, and though none of them represent a “cure,” all are important tools to be used by oncologists. There is much ongoing research to improve techniques in all three areas.
At the same time, many researchers and firms are seeking on approaches to complement these three core techniques. Many of these have promising science behind them, and appear to be gaining a place in the toolkit as well.
A word of caution: these approaches are at various places in the clinical trial / approval pipeline, and patients should discuss with their doctors, or a team at a major brain tumor center, to identify a treatment strategy for you.
Status: FDA approved in newly diagnosed and recurrent brain tumors
GammaTile is an approach in which a neurosurgeon removed as much tumor tissue as possible, and then implants a small wafer into the tumor bed, where it delivers highly targeted doses of radiation to help prevent regrowth. The technique is for operable brain tumors, including gliomas, meningiomas, and metastases. Compared to traditional radiation therapy, GammaTile should keep localized to protect healthy brain tissue. In a clinical study, patients experienced better local control compared to previous treatments.
Status: FDA Approved in newly diagnosed and recurrent brain tumors
Optune, a device that consists of an array of electromagnetically-charged nodes worn on the scalp, is an FDA-approved adjunct therapy for brain tumors. Most patients on Optune are also receiving chemotherapy or radiation. The technique, also known as “tumor-treating fields” interferes with a tumor’s cell division, leading to longer periods of no disease progression for patients using Optune plus TMZ compared to patients who on TMZ alone. The device will generally be worn nearly 100% of the time to be maximally effective.
Status: Pre-clinical Trials
Two big problems vex doctors trying to treat brain tumors. One is the blood brain barrier and the other is targeting treatments so as to damage tumor tissue but spare healthy brain. Sonodynamic therapy (SDT) is an approach currently being explored by researchers at the Ivy Brain Tumor Center in Phoenix, AZ. With this technique, drugs are introduced into the brain that only become toxic once they’re exposed to ultrasound. So two levels of targeting are involved. First, researchers start with a drug that is selectively absorbed by tumors. Second, they aim the ultrasound so the drug only becomes activated right where it is needed, sparing nearby tissue.
BBB Drug Delivery Systems – Lipid or Polymer Nanoparticles
Status: Various clinical trials
The other problem mentioned above, the blood-brain barrier (BBB), makes drug treatment of any central nervous system disease challenging. Temozolamide (TMZ), which became FDA approved in 2005, does cross the BBB, but many newer molecules that researchers are developing do not. Fortunately, many researchers are also investigating molecules that can help future drugs cross BBB. A common theme in these approaches is the use of bio-engineered nanoparticles that are small enough or feature surface adaptations that allow passage across the BBB. Some of thee nanoparticles may even be candidates to help deliver gene therapies to tumor sites.