What is your approach to a patient with an advanced stage diffuse large B-cell lymphoma treated with chemotherapy alone (with a PET CR) who then develops an isolated CNS relapse?  

If the patient cannot tolerate methotrexate or further chemotherapy, how effective is radiation therapy (e.g. WBRT) in rendering the patient disease-free?  If they only have a single brain lesion, would you consider local RT over WBRT?  

Answer from: Radiation Oncologist at Academic Institution