Second-Line Treatments Expanding for Recurrent Brain Cancers

A once-discarded approach to radiation therapy for brain tumors has re-emerged as a solid secondary treatment for refractory disease.

Surgically targeted radiation therapy (STaRT),a form of Cesium-131 brachytherapy, is now used in cases of recurrent glioblastomas (GBM), other high-grade gliomas, high-grade meningiomas, and brain metastases. Cleveland Clinic’s Weston Hospital is one of a handful of centers in Florida, and the first across the Cleveland Clinic enterprise, to offer STaRT.

“Glioblastomas are the most common type of malignant brain tumor in adults and the most difficult to treat, with a high degree of recurrence,” says Hamid Borghei-Razavi, MD, Director of the Minimally Invasive Cranial and Pituitary Surgery Program at Cleveland Clinic Florida’s Brain Tumor Center. “While surgery, conventional radiation, and chemotherapy remain our first-line treatments for glioblastoma and most other malignant tumors, it is important that we have additional modality for patients with refractory disease, including laser ablation and now Cesium-131 brachytherapy.”

Surgically targeted radiation therapy (STaRT)

Cesium-131 brachytherapy first made inroads as a treatment for prostate cancer. With a shorter half-life and energy path, it provides a more localized distribution of radiation. Directly following resection of the recurrent tumor, bioresorbable, flexible collagen tiles are permanently placed in the resection cavity. The GammaTile® deliver immediate, dose-intense radiation within a few millimeters of the operative bed where recurrences are more likely to develop.

“The radiation delivery starts immediately and the dose is more targeted than external beam radiation, and most of it is delivered within the first month following placement,” explains Dr. Borghei-Razavi. “Now we can immediately target the area with radiation instead of waiting weeks for wound healing to commence standard radiation therapy. This change in treatment timing is a real game changer.”

Patients most likely to benefit are those with recurrent high-grade meningiomas who have already undergone multiple rounds of radiosurgery or those with glioblastomas who have exhausted all other treatment options.

Dr. Borghei-Razavi notes that Cesium-131 brachytherapy is less likely to exhibit the excess radiation and radiation necrosis observed with earlier forms of brain tumor brachytherapy. “We are hopeful that STaRT will improve survival and quality of life for patients who meet certain criteria,” he says.

Laser interstitial thermal therapy (LITT)

Laser interstitial thermal therapy is another second-line treatment option available for recurring tumors and for malignancies located in deep-set areas of the brain that are difficult and a high risk to access. LITT is a form of precision laser ablation in which a stereotactically placed laser probe is used to heat the tumor tissue while sparing surrounding healthy tissue. Dr. Borghei-Razavi and his colleagues at Cleveland Clinic Florida use the robotic NeuroBlate™ system to perform the MRI-guided procedure.

“It requires just a small hole to be made in the skull, about 7 mm in diameter, and the controlled heating under MRI visualization allows us to be very precise in the tissue we target,” says Dr. Borghei-Razavi. “It is a minimally invasive cytoreduction option for patients who are not candidates for traditional open craniotomy.”

The role of the tumor board

As the therapeutic landscape for recurring brain tumors expands, choosing the best therapy requires a thoughtful, multidisciplinary approach, cautions Dr. Borghei-Razavi. “The best outcomes are achieved when we match innovative treatments with properly selected patients,” he adds.

Cleveland Clinic Florida’s brain tumor board includes neurosurgeons, neuro-oncologists, neuroradiologists, radiation oncologists, neuropathologist, endocrinologists and neuropsychologists who meet to review complex cases and determine the most effective treatment plan for each patient.