MRI surveillance improved cognition in small-cell lung cancer trial

Brain MRI surveillance without prophylactic cranial irradiation significantly improved cognitive failure–free survival compared with MRI surveillance plus irradiation in the randomized phase III SWOG S1827 MAVERICK trial involving patients with small-cell lung cancer. The international study found that the cognitive benefit was consistent among patients with both limited-stage and extensive-stage disease. At a preliminary analysis, there was no apparent difference in overall survival between the groups, although the investigators said the final survival analysis would be conducted after 190 deaths, compared with 128 recorded when the interim results were presented.

Researchers enrolled 304 patients with limited-stage or extensive-stage small-cell lung cancer who had completed initial therapy and had no brain metastases detected by MRI. Participants were randomly assigned to brain MRI surveillance alone or to MRI surveillance plus prophylactic cranial irradiation, known as PCI. Sixty-eight percent of the participants had limited-stage disease. Brain MRI scans were scheduled every three months during the first year and every six months during the second year, with standardized cognitive testing performed at the same intervals.

The trial’s primary endpoint was cognitive failure–free survival, defined as the time from randomization until either cognitive failure or death. Cognitive failure was a decline in performance on any one of a battery of six standard cognitive tests. After a median follow-up of 22 months among living patients, MRI surveillance alone was associated with significantly better cognitive failure–free survival than MRI surveillance plus PCI. The hazard ratio was 0.60, with a 90% confidence interval of 0.46–0.78 and a P value of 0.0005. The investigators reported that the benefit was similar in patients with limited-stage and extensive-stage disease and was not significantly affected by receipt of immunotherapy.

PCI was developed as a strategy to reduce the incidence of brain metastases in small-cell lung cancer. Older studies from the period before routine brain MRI reported an overall-survival advantage with PCI, leading it to become a standard treatment. The MAVERICK trial instead evaluated regular MRI surveillance, which can identify brain metastases earlier and permit treatment while avoiding irradiation-associated neurocognitive toxicity. Preliminary overall-survival results showed no apparent difference after 128 deaths: the hazard ratio for MRI surveillance alone was 0.90, with a 90% confidence interval of 0.67–1.20. Progression-free survival also did not differ significantly between groups. Because the survival analysis was preliminary and the planned event count had not yet been reached, these results do not establish definitive equivalence in overall survival.

Based on the reported findings, principal investigator Chad Rusthoven said the results support MRI surveillance alone for patients with small-cell lung cancer. SWOG Cancer Research Network led the National Cancer Institute-supported trial, which was conducted through the National Clinical Trials Network. The randomized design, standardized cognitive assessments and scheduled MRI surveillance allowed the researchers to compare the two strategies directly in patients who had completed initial therapy without detectable brain metastases. The strongest evidence from the reported analysis concerns the trial’s primary cognitive endpoint, while final overall-survival results remain pending.

Subject of Research: Randomized comparison of brain MRI surveillance and prophylactic cranial irradiation for cognitive and survival outcomes in small-cell lung cancer

Article Title: Brain MRI surveillance without prophylactic cranial irradiation improves cognitive outcomes in small cell lung cancer

Article References: Brain MRI surveillance without prophylactic cranial irradiation improves cognitive outcomes in small cell lung cancer. Original publication (Bibliographic details unavailable.)

Image Credits: AI Generated

DOI: Not provided

Keywords: small-cell lung cancer, brain MRI, prophylactic cranial irradiation, cognitive function, cognitive failure–free survival, overall survival, brain metastases, randomized clinical trial, SWOG S1827, MAVERICK trial, Brain, surveillance