Proton Craniospinal Radiation Therapy vs. Partial Photon Radiation Therapy for Leptomeningeal Metastasis From Solid Tumors

Inclusion Criteria:

Patient with solid tumor malignancy with leptomeningeal metastases established radiographically and/or through CSF cytology
Patients who are candidates for radiation therapy for the treatment of leptomeningeal metastases
Patients of all ages
KPS ≥ 60 for participants ≥ 16 years old, and Lansky ≥ 60 for participants < 16 years old
For adult patient, the patient/ legally authorized representative is able to provide informed consent. For pediatric patient, a parent is able to provide informed consent.

Adequate bone marrow function:

Hemoglobin > 8g/dL
Absolute neutrophil count >1,000/mm
Platelet count > 100,000/mm
Female subjects must either be of non-reproductive potential (i.e. pediatric patients, OR postmenopausal by history [≥ 60 years old, or with no menses for >1 year without an alternative medical cause], OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy) or must have a negative serum pregnancy test within 2 weeks prior to starting treatment.
Patient at reproductive potential must agree to practice an effective contraceptive method.

Exclusion Criteria:

Patient with multiple, serious major neurologic deficits per physician/investigator assessment including encephalopathy
Patient with extensive systemic disease and without reasonable systemic treatment options
Patient who is unable to undergo MRI brain and spine with gadolinium contrast
Previous radiotherapy to the intended treatment site that precludes developing a treatment plan that respects normal tissue tolerances
Pregnant or lactating women.