Lapatinib Ditosylate Concentration and Activity within Tumors in Patients with Neurofibromatosis Type 2 or Acoustic Schwannoma Undergoing Surgery

Inclusion Criteria

• Patients must meet diagnostic criteria for NF2 including presence of bilateral VS (10 patients) or idiopathic VS without evidence of genetic syndrome (10 patients)
• VS surgery determined clinically necessary by the treating physician and scheduled within 4 weeks
• Normal cardiac left ventricular ejection fraction (LVEF) by multiple-gated acquisition (MUGA) scan or transthoracic echocardiogram
• Patients must have a Karnofsky performance status >= 60% (i.e. the patient must be able to care for himself/herself with occasional help from others)
• Absolute neutrophil count >= 1,000/mm^3 (unsupported)
• Platelet count >= 75,000/mm^3 (unsupported)
• Hemoglobin >= 8 g/dL (transfusion support allowed)
• Creatinine =< 1.5 times upper limit of normal (ULN) OR glomerular filtration rate >= 70 ml/min
• Bilirubin =< 1.5 times ULN
• Alanine aminotransferase (ALT) =< 2.5 times ULN
• Patients must be able to provide written informed consent
• Any neurologic deficits must be stable for >= 1 week
• Patients must be able to swallow tablets
• Patients with the potential for pregnancy or impregnating their partner must agree to follow acceptable birth control methods to avoid conception; women of childbearing potential must have a negative pregnancy test
• Patients must suspend the use of P450 inducing or P450 suppressing agents for a minimum of 10 days prior to starting lapatinib
• Patients must be able to undergo a pre-surgical magnetic resonance imaging (MRI) brain

Exclusion Criteria

• Patients with serious concurrent infection or medical illness, which would jeopardize the ability of the patient to receive the treatment outlined in this protocol with reasonable safety
• Patients who are pregnant or breast-feeding
• Patients receiving concurrent therapy for their tumor (i.e. chemotherapeutics or investigational agents, radiation or immunotherapy) within 4 weeks of the first dose of the study drug
• Patients with a concurrent or prior malignancy are ineligible unless they are patients with curatively treated carcinoma-in-situ or basal cell carcinoma of the skin; patients who have been free of disease (any prior malignancy) for >= five years are eligible for this study
• Patients cannot have received cytochrome P450-inducing anticonvulsants (enzyme-inducing antiepileptic drugs [EIADs]; e.g., phenytoin, carbamazepine, phenobarbital, primidone, oxcarbazepine) or similar agents (e.g., rifampin) or P450 inhibiting agents (ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole) within 10 days prior to starting lapatinib
• Significant gastrointestinal disorder(s), in the opinion of the principal investigator (e.g., Crohn’s disease, ulcerative colitis, extensive gastric resection)
• Neurologic deficits that are rapidly progressing; all neurologic signs and symptoms must have been stable for a week prior to first dose
• Patients cannot have known cardiac disease (either arrhythmia or congestive heart failure) requiring treatment