Cancer Patients Who Experience Cognitive Decline After Radiation Treatment for Brain Metastases May Regain Full Neurocognitive Function, New Study Suggests

October 01, 2024

Nearly 40 percent of cancer patients who experienced memory loss, brain fog and other cognitive difficulties after radiation treatment for brain metastases regained full neurocognitive function within six months, according to a new analysis by radiation oncology researchers at the University of Maryland Greenebaum Comprehensive Cancer Center (UMGCCC).

The study also found that patients were more likely to recover from these cognitive side effects if they received highly targeted radiation treatments vs. standard whole-brain radiation. Researchers defined cognitive recovery as having no evidence of impairment based on a series of sophisticated cognitive tests.

The findings from an analysis of cognitive testing data from 288 patients in three large, randomized Phase III clinical trials were presented today at a press briefing at the annual meeting of the American Society for Radiation Oncology (ASTRO) in Washington, D.C. It was one of two studies by University of Maryland Department of Radiation Oncology researchers highlighted at the briefing.

Hua-Ren Ryan Cherng, MD, the lead author of the brain radiation study and a fifth-year radiation oncology resident at UMGCCC within the University of Maryland Medical Center (UMMC), said the results may help physicians counsel their patients about treatment options and recovery from potential cognitive side effects.

"No longer should we be viewing cognitive dysfunction as a permanent endpoint for patients," Dr. Cherng said. "It is not uncommon for patients to experience cognitive issues following radiation therapy, especially whole-brain radiation, but we didn't know how they would fare long-term. Now we have data that show that they can get better within months with no symptoms and sustain that recovery over time."

Brain metastases are cancers that have spread to the brain from other parts of the body. About 200,000 people are diagnosed with brain metastases each year in the U.S. Treatments include whole-brain radiation or more targeted treatments, such high-dose stereotactic radiosurgery or a type of whole-brain radiation that avoids treating the hippocampus, a key structure in the brain that controls cognition and memory.

With more targeted radiation, systemic therapies and earlier detection, these patients are living longer, and cognitive side effects are a major quality-of-life concern for them, Dr. Cherng said. "They still want to share memories and make new memories with their loved ones. Cognition is a critical part of their lives."

The researchers analyzed data from long-term cognitive testing from three clinical trials that measured neurocognitive outcomes two conducted by the North Central Cancer Trials Group and one by NRG Oncology.

Of the 288 patients in the study who experienced cognitive problems, 38 percent fully recovered at six months and 42 percent at one year. There were also patients who showed improvement on cognitive tests but had not achieved full recovery -- 73 percent at six months and 76 percent at one year. Some patients were followed for two years, and two-thirds of them continue to show no sign of cognitive issues.

Mark V. Mishra, MD, an associate professor and Vice Chair of Clinical Research in the Department of Radiation Oncology at the University of Maryland School of Medicine (UMSOM) and a radiation oncologist at UMGCCC, is the study's senior author.

The Greenebaum Comprehensive Cancer Center is located at UMMC, the academic flagship of the University of Maryland Medical System (UMMS), and is one of 57 National Cancer Institute (NCI)-designated cancer centers in the U.S.

Also featured today at the ASTRO press briefing was a study that explored factors that may influence Black patients' participation in cancer-related clinical trials. Nationally, Black individuals are underrepresented in clinical trials compared to Whites. Ninety-seven cancer patients — 30 percent of them Black — responded to questions on a survey between October 2023 and February 2024. Among the findings:

• Black patients were more than five times as likely to agree that death or illnesses were determined by God's will and that God determined wellness
• 20 percent of Black patients said they agreed that research harmed minority populations, compared to zero non-Black patients
• Black participants were 10 times more likely than non-Black participants to say that they felt they and the community had nothing to gain from participating in clinical research

"Our research has identified some really important themes that should be discussed with patients as part of the recruitment process, such as spirituality or faith, as well as recognizing the elephant in the room that is a justifiable mistrust stemming from structural racism and historical practices in clinical trial programs," said Charlyn Gomez, the study's lead author and a third-year medical student at UMSOM. "But on the positive side, we also found there is trust in the medical care team and perhaps we can build from there."

Melissa Ana Liriano Vyfhuis, MD, PhD, an associate professor of radiation oncology at UMSOM and a radiation oncologist and medical director of radiation oncology at The Cancer Center at the University of Maryland Capital Region Health in Largo, Md., an UMMS member organization, is the study's senior author.