Poorer Survival for Patients with Multifocal Glioblastoma at Diagnosis
“Two small previous studies were contradictory; our study appears to confirm observations that disease in patients with more than one lesion is particularly challenging and that these patients tend to have worse outcomes,” reported lead author Chirag G. Patil, MD, director of the Center for Neurosurgical Outcomes Research, Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California.
Survival analysis of 47 patients with multifocal glioblastoma multiforme and 47 single-lesion glioblastoma patients, matched for age, functional impairment scores, residual tumor margins, radiotherapy, and chemotherapy history, showed that median overall survival (OS) for the multifocal group was 6 months (95% CI, 4-10 months), versus 11 months (95% CI, 10-19 months) for single-tumor patients (log-rank test P=0.02).
“Patients with multifocal disease in the modern temozolomide era had 1-year and 2-year survival rates of only 28.5% and 4.3%, respectively,” the authors wrote.
Mortality hazard was twice as high for patients with multifocal glioblastoma as for those with a lone tumor, the authors report.
“We've known that certain independent factors, such as age at diagnosis, amount of residual tumor after surgery, and the patient's functional status are useful in predicting outcomes in patients with glioblastoma multiforme, but multifocal disease at time of onset has rarely been examined in this context,” noted Patil.
While the precise molecular mechanisms of glioblastoma multifocality remain unknown, “it is presumed that malignant glial cells in multifocal glioblastoma have an increased ability and propensity to disseminate along existing cytoarchitectural structures such as neurons, white matter tracks, and blood vessels,” the authors wrote.