In a small but compelling retrospective case series of nine EGFR mutant lung cancer patients with brain or leptomeningeal metastases that occurred despite conventional dosing of an EGFR inhibitor, patients were treated with high dose “pulsatile” erlotinib (1,500 mg weekly) and a CNS partial response rate of 67% (6 of 9 patients) was noted; however, median time to CNS progression was only 2.7 months (36). Here, EGFR is linked to lung carcinoma.