Pivotal, Open-label, Randomized Study of Radiosurgery With or Without Tumor Treating Fields (TTFields) for 1-10 Brain Metastases From Non-small Cell Lung Cancer (NSCLC).

⁃ 18 years of age and older

⁃ Life expectancy of ≥ 3 months

⁃ New diagnosis of brain metastases from a histologically or cytologically confirmed primary or metastatic NSCLC tumor within 5 years of registration on the study. If the original histological proof of malignancy is greater than 5 years, then pathological confirmation is required (i.e.: from extra-cranial or intracranial disease).

• 1 inoperable brain metastasis or 2- 10 brain lesions per screening MRI, confirmed by contrast enhanced MRI amenable to SRS according to the following criteria:

⁃ a. largest tumor volume < 10 cc b. longest tumor diameter < 3 cm c. Cumulative volume of all tumors ≤ 15 cc 6. At least one measurable disease per study protocol 7. Patients must be receiving optimal therapy for their extracranial disease according to local practice at each center. Patients may continue on systemic therapy while receiving TTFields.

• Able to operate the NovoTTF-200M device independently or with the help of a caregiver 9. Clinical trials prior to enrollment are allowed, as long as no brain directed therapy was included (current treatment trials are exclusionary)