MRI Scan of Glioblastoma multiforme.
Glioblastoma multiforme (GBM) is one of the most medically challenging brain tumors, and can be fatal within one year.¹ Approximately 18,000 patients are diagnosed with GBM in the U.S., annually.² The current standard of treatment—maximal resection, followed by radiation with concurrent and adjuvant temozolomide chemotherapy has shown only modest improvement, with a median survival of 14.6 months, and a two-year survival rate of 26.5 percent.¹ “We need new avenues to improve survival rates,” says Assistant Professor of Neuro-Oncology Dawit Aregawi, M.D. He explains that Penn State Hershey Medical Center is conducting trials in immunologically-mediated therapy among the 90 percent of patients who experience tumor recurrences.³
While past GBM research has focused on chemotherapy, scientists have switched their focus to therapy utilizing the body’s own immune system to create tumor-fighting vaccines. Two upcoming phase 1 trials at Penn State Hershey, ICT-121 and WT2725, target cancer stem cells traditionally resistant to any form of treatment. Continue reading
Two major challenges of treating glioblastoma multiforme have been the type and location of these aggressive brain tumors.¹ Surgical tumor resection is difficult due to the widespread nature of gliomas. Chemotherapeutic treatments are often unable to cross the blood-brain barrier or cannot be confined to cancerous cells only, thus causing toxicity in normal tissue.¹ One viable option is targeted therapy, which can result in both improved chemotherapeutic and surgical results.
Research initiated by Achuthamangalam Madhankumar, Ph.D., assistant professor of neurosurgery at Penn State Hershey, has shown it is possible to use targeted nanovesicles to carry anti-cancer drugs or contrast agents selectively to tumor cells. The latter approach enhances tumor visibility, enabling the surgeon to more accurately assess the extent of the tumor. In addition, because of the unique expression of the interleukin-13 (IL-13) receptor on certain types of brain tumors, this targeted delivery system may be useful in the diagnosis of tumors.
The research used a murine model to test parameters including the efficacy of targeted versus untargeted liposomal doxorubicin, a chemotherapeutic agent.¹ Mice with intracranial tumors measuring five millimeters received fifteen milligrams of doxorubicin for each kilogram of body weight once a week.¹ Over six weeks, the size of the tumor decreased to less than one millimeter in the group receiving targeted liposomes, but did not decrease in the two of eight surviving mice receiving untargeted liposomes with doxorubicin.¹ There was a significant decrease in the tumor volume on contrast MRI images in the targeted liposome group, as seen in the figure.¹ Continue reading
UP TO 50 PERCENT OF BRAIN TUMORS RESISTANT TO STANDARD CHEMOTHERAPEUTIC AGENT TMZ
When a patient presents with a malignant glioblastoma, the current standard therapy is total resection surgery followed by radiation, either alone or in combination with temozolomide (TMZ) chemotherapy.1 Used to treat several types of cancer, orally-administered alkylating agent TMZ is known to inhibit cell reproduction by blocking the replication of DNA.2 Although it is less toxic than other alkylating agents, TMZ does not display efficacy in as many as 50 percent of brain tumors.3 Because of this, as well as the high rate of chemotherapy resistance in recurrent brain malignancies, there is an urgent need for new drugs for treatment-resistant tumors.4 Continue reading
Penn State Milton S. Hershey Medical Center recently completed its 1,000th Gamma Knife radiosurgery procedure. Gamma Knife radiosurgery uses a single dose of radiation instead of a surgeon’s scalpel to treat a wide range of diseases, including both benign and malignant tumors, Parkinson’s disease, vascular malformations and lesions that cause epilepsy.
Penn State Hershey’s 1,000th Gamma Knife patient was Robert Reynolds from Mifflintown, Juniata County. Reynolds was treated for lung cancer that had spread to his brain. Since undergoing the procedure, Reynolds has returned to work as a Juniata County commissioner.
“We were able to treat five lesions in Mr. Reynolds’ brain,” said Dr. Jonas Sheehan, director of neuro-oncology at Penn State Hershey. “His case is a great example of how our experienced neurosurgeons and radiation oncologists are able to provide advanced care that allows patients with complex conditions to enjoy a high quality of life.” Continue reading