Brief Summary
This phase III trial compares proton craniospinal irradiation (pCSI) to involved-field radiation therapy (IFRT) for the treatment of breast or non-small cell lung cancer that has spread from where it first started to the cerebrospinal fluid filled space that surrounds the brain and spinal cord (leptomeningeal metastasis). Patients with leptomeningeal metastasis (LM) may develop multiple areas of nervous system (neurologic) impairment that can be life-threatening. Radiation therapy (RT) effectively relieves local symptoms due to LM. RT uses high energy radiography (x-rays), particles, or radioactive seeds to kill cancer cells and shrink tumors. IFRT is commonly used to treat symptoms of LM. IFRT is radiation treatment that uses x-rays to treat specific areas of LM and to relieve and/or prevent symptoms. pCSI uses protons that can be directed with more accuracy than x-rays which allows treatment of the entire central nervous system space containing the cerebrospinal fluid (CSF), brain, and spinal cord. The pCSI treatment could delay the worsening of LM. Giving pCSI may be better than IFRT in treating LM in patients with breast or non-small cell lung cancer.
Protocol Interventions
Procedure: Biospecimen Collection, Procedure: Computed Tomography, Procedure: Lumbar Puncture, Procedure: Magnetic Resonance Imaging, Procedure: Positron Emission Tomography, Radiation: Proton Beam Craniospinal Irradiation, Other: Quality-of-Life Assessment