Study of Proton Radiation to the Brain and Spinal Cord for Patients With Leptomeningeal Metastases

Inclusion Criteria:

- Female subjects must either be of non-reproductive potential (i.e. post-menopausal by
history: >/= 60 years old and 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 with solid tumor malignancy with leptomeningeal metastases established
radiographically and/or through CSF cytology.

- KPS ≥ 60.

- Age ≥ 10 years.

- For adult patient, the patient is able to provide informed consent. For pediatric
patient, a parent is able to provide informed consent.

- Patient at reproductive potential must agree to practice an effective contraceptive
method.

- Adequate bone marrow function:

- Hemoglobin ≥ 8g/dL

- Absolute neutrophil count ≥500/mm^3

- Platelet count ≥ 100,000/mm^3

Exclusion Criteria:

- Patient with multiple, serious major neurologic deficits 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.