More studies are needed to find the most effective dose of methotrexate and to find a combination therapy that will produce even better results, Batchelor said. "The question is whether adding other drugs will make patients do better," he said.
"We are looking for drugs that act against lymphoma and actually get into the nervous system," Batchelor said. "We have a new trial where we will be adding three additional drugs to methotrexate. We hope we are going to see even more patients achieve long-term remission."
One expert believes that, based on these findings, methotrexate could save many patients from having to undergo harmful brain radiation.
"Methotrexate is to date the most effective reported drug in primary central nervous system lymphoma," said Dr. Paul Graham Fisher, an associate professor of neurology and the Beirne Family Director of Neuro-Oncology at Packard Hospital at Stanford University.
This is encouraging because in some rare instances patients may not need radiation treatment, Fisher said. "As a cautionary note, the numbers of patients are small, and we need to see greater extension of this work, and also with monitoring patients for leukoencephalopathy (destruction of fibers covering nerve cells), apparently seen more widely when used in children with leukemia," he said.
Methotrexate is commonly used in chemotherapy and is also used in treating autoimmune diseases such as Crohn's disease, psoriasis and arthritis.
For more on primary central nervous system lymphoma, visit the U.S. National Cancer Institute.
SOURCES: Tracy Batchelor, M.D., associate professor, neurology, Harvard University, and executive director, Stephen E. &
All rights reserved