Christina I. Tsien, MD
DISCUSSANT OF the NRG-CC001 trial, Christina I. Tsien, MD, Professor of Radiation Oncology at Washington University School of Medicine, St. Louis, underscored the importance of this research, noting that cognitive impairment affects nearly 50% of patients who undergo whole-brain radiation therapy. Nevertheless, said Dr. Tsien, additional time is needed to verify these outcomes.
“Median follow-up is still only 8 months, so we want to make sure that there is no difference in either intracranial control or overall survival between both groups with longer follow-up,” said Dr. Tsien. “The benefits of this approach have to be weighed against the potential protection of microscopic brain disease in this region, although the data so far have shown this to be extremely low.”
Dr. Tsien also noted that radiation-induced cognitive impairment is multifaceted as higher cognitive function is predominant in the prefrontal cortex, underlining the likelihood that neurocognitive decline reflects alterations in multiple brain regions, and not only the hippocampus. However, for patients with good performance status and a controlled primary with brain metastases requiring whole-brain radiotherapy, said Dr. Tsien, hippocampal-sparing whole-brain radiotherapy using intensity-modulated radiotherapy plus memantine should be considered.
"It’s a very complex era for patients with brain metastases,” said Dr. Tsien. “There are multiple options including best supportive care, stereotactic radiosurgery, hippocampal sparing whole-brain radiation, as well as novel systemic therapies including immunotherapy and targeted therapies, which require consideration of a careful balance between toxicity and outcome. While novel systemic therapies are quickly evolving, this study highlights that in patients who require whole-brain irradiation and who are predicted to live longer than 4 months, hippocampus-sparing whole-brain radiotherapy and memantine should be considered.” ■
DISCLOSURE: Dr. Tsien reported relationships with Merck and Varian.
