Correct!
2. Metastatic brain tumors that have 4-anaplastic lymphoma kinase (ALK) translocations will respond to crizotinib
Among patients with lung cancer, 50% have brain metastases. Prophylactic cranial irradiation has been shown to be beneficial in small cell lung cancer, but there is not enough data for NSCLC. Surgical resection should be considered in those with solitary brain metastasis and good prognosis characteristics. Whole brain radiotherapy (WBRT) should be considered after surgical resection to reduce local recurrence and the risk of developing additional brain metastases. However, WBRT does not offer substantial benefit NSCLC patients with a poorer prognosis based on prognostic scores.
Stereotactic radiosurgery is a technique of radiation delivery that allows for a greater single-dose fractionation of radiation-thereby reducing radiation dose to surrounding brain tissue and theoretically causing fewer neurocognitive side effects that WBRT. It should be used in patients who are not surgical candidates and have 1-4 brain metastases. Stereotactic radiosurgery can be considered as an alternative to surgical resection. Systemic agents (i.e., radiosensitizing medications and cytotoxic drugs) do not improve meaningful outcomes.
Recently, chemotherapy has been shown to benefit two molecular defined populations of NSCLC patients. EGFR mutations can be treated with EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib or erlotinib. EGFR inhibitors have an intracranial response approaching 80%.
Tumors with 4-anaplastic lymphoma kinase (ALK, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase) translocations respond to crizotinib. Unfortunately, brain metastasis do not respond well to crizotinib despite an excellent effect on extracranial disease. This may due to the poor penetration of crizotinib through the blood-brain barrier in some patients.
Our patient was started on levetiracetam (Keppra) and dexamethasone. Radiation oncology was consulted and the underwent mapping for whole-brain radiation. She was discharged with follow-up with oncology to consider chemotherapy.
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