Laser Ablation After Stereotactic Radiosurgery for Patients With Metastatic Brain Tumors. (LAASR)

Patients will have been already, as part of normal clinical practice, schedulled for NeuroBlate/AutoLITT based neurosurgery to treat metastatic brain tumors that have previously been treated with Stereotactic Radiosurgery (SRS), but have developed either progression or radiation necrosis (as assesed by MRI) of the SRS treated tumors.

Inclusion Criteria:

1. Up to 3 target supratentorial metastatic lesions (up to 5 cm in maximum dimension perpendicular to planned primary trajectory axis) previously treated with SRS, with radiological evidence of progression, pseudoprogression or radionecrosis. Subject may have up to 5 non target lesions present. Non target lesions must be small (less than 3 mm) or not expected (in Investigator's judgment) to contribute to symptomology during the course of the study or confound interpretation of radiological and clinical measures.
2. Target tissue/tumors treatable with one or two NeuroBlate trajectories per tumor.
3. Patient and condition amenable to NeuroBlate, but surgery is not preferred (due to lack of mass-effect, tumor located in an eloquent region, or circumstances where, in the PI-neurosurgeon's judgment, resection could result in long-lasting neurological deficits).
4. Patients with stable systemic primary malignancy.
5. KPS ≥ 70.
6. Age >18 years.
7. Tumor clearly defined on gadolinium enhanced T1 or MP-RAGE, or comparable MRI sequence with midline shift < 1 cm.

8. Minimum interval since last drug therapy:

   1. 2 weeks since last non-cytotoxic therapy,
   2. 3 weeks since last Avastin treatment,
   3. 3 weeks must have elapsed since the completion of a non-nitrosourea containing chemotherapy, and
   4. 6 weeks since the completion of a nitrosourea containing chemotherapy regimen.
9. Patients must be able to provide written informed consent.

Exclusion Criteria:

1. Females who are pregnant or breast feeding.
2. Leptomeningeal metastases.
3. Uncontrolled infectious process.
4. Symptoms due to mass effect of the tumor (with steroid treatment), including marked edema, significant midline shift (e.g., > 5 mm) or high intracranial pressure, where surgical debulking in the first 30 days post NeuroBlate treatment would be required for therapy.
5. Uncontrolled hypertension (systolic >180 mm Hg), angina pectoris, or cardiac dysrhythmia, or recent (within 6 weeks) history of intracranial hemorrhage.
6. Serious infection, immunosuppression or concurrent medical condition (chronic or acute in nature) that may prevent safe participation or ability to meet follow-up requirements.
7. Abnormal absolute neutrophil count (ANC<1500/mm3), or PT and aPTT (>1.5x institutional upper limit), platelets (<100,000/mm3) or hemoglobin (<10 gm/dL), or the administration of antiplatelet agents within 7 days prior to treatment.
8. Inadequate bone marrow, liver and renal function (e.g., total bilirubin > 1.5 x ULN; AST, ALT > 2.5 x ULN; alkaline phosphatase > 2.5 x ULN; serum creatinine > 1.5 x ULN).
9. Patients whose physical dimensions cannot be accommodated in the MRI scanner or patients with contraindications to MRI imaging such as pacemakers, non-compatible aneurysm clips, shrapnel and other internal ferromagnetic objects.
10. Other concurrent medical or other condition (chronic or acute in nature) that in the opinion of the investigator may prevent safe participation or otherwise render this patient ineligible for the study.
11. Patients with treatable tumors (those of the size described in the first Inclusion Criterion) involving the posterior fossa (brainstem and cerebellum) will be excluded as will patients where the anticipated treatment margin will be within 5 mm of critical intracranial structures (e.g., primary branches of cerebral vessels, dural sinuses, hypophysis or cranial nerves).