Preventive Chemotherapy Slashes the Risk of Lymphoma Spreading to the Central Nervous System
Certain types of lymphoma and certain patients with lymphoma are predisposed to the disease metastasizing in the brain.
However, preventive chemotherapy can reduce that risk from about 25% to 2 or 3%. Oncologist Charles M. Farber, PhD, MD, explains.
Why is it important to talk about systemic lymphoma in regard to the central nervous system?
Approximately 75,000 to 80,000 individuals are diagnosed with non-Hodgkin’s lymphoma – cancer of the lymphatic system including the lymph nodes – every year. We know certain lymphomas tend to enter the central nervous system and reach the brain. This includes aggressive lymphomas, high-grade lymphomas and individual subtypes such as Waldeyer’s ring lymphoma and mantle cell lymphoma. Patients whose disease is not confined to the lymph nodes and who are immunosuppressed are also predisposed to central nervous system lymphoma.
What does treatment for central nervous system lymphoma entail?
The central nervous system is like a sanctuary for cancer cells because most traditional chemotherapies cannot penetrate the blood-brain barrier (hence our saying in oncology, “Chemotherapy in the vein does not penetrate the brain”). While the blood-brain barrier naturally protects the central nervous system from bacteria and viruses, it doesn’t keep all pathogens out … or necessarily allow cancer-fighting drugs in. This requires us to take a more direct approach in administering chemotherapy to the central nervous system. Beyond chemotherapy, treatment can also entail surgical removal of the tumor(s) and/or targeted radiation therapy.
Is preventive therapy available?
Yes, preventive therapy is critical for individuals who are at high risk for central nervous system lymphoma. We start by proactively identifying those who are most likely to be affected and then administer a low dose of chemotherapy directly into the cerebrospinal fluid through a series of lumbar punctures. This enables the chemotherapy to penetrate the blood-brain barrier and enter the central nervous system. This preventive measure can reduce the likelihood of a patient developing brain metastases by approximately 90%.
How do you instill hope in patients facing a difficult prognosis despite these advancements?
I focus on sharing stories from other patients who have rallied and done much better than anticipated, even when they were in statistically tough situations. I also encourage them to believe in the power of positivity. Of course we don’t have statistics to measure that, but I will tell you people who have a positive outlook seem to do much better overall. I encourage them to fight on and be optimistic as we use every resource available – including new advances in medicine happening all the time – to provide the best possible outcome.