Patient description: The patient is a 35-year-old woman with myasthenia gravis, class IIa. She complains of diplopia and fatigue and weakness that affects mainly her upper limbs. She had a positive anti-AChR antibody test, and her single fiber electromyography (SFEMG) was positive. She takes pyridostigmine 60 mg three times a day. But she still has some symptoms that interfere with her job. She is a research coordinator and has 3 children. Her 70-year-old father has hypertension. She does not smoke or use illicit drugs. She drinks alcohol occasionally at social events. Her physical exam and lab studies were not remarkable for any other abnormalities. BP: 110/75 Hgb: 11 g/dl WBC: 8000 /mm3 Plt: 300000 /ml Creatinine: 0.5 mg/dl BUN: 10 mg/dl Beta hcg: negative for pregnancy

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Advanced Digestive System Neuroendocrine Neoplasm Duodenal Neuroendocrine Tumor G1 Functional Pancreatic Neuroendocrine Tumor Gastric Neuroendocrine Tumor Intermediate Grade Lung Neuroendocrine Neoplasm Low Grade Lung Neuroendocrine Neoplasm Nonfunctional Pancreatic Neuroendocrine Tumor Thymus Neoplasm Histologically or cytologically confirmed low or intermediate grade, unresectable well differentiated foregut neuroendocrine tumors (thymic, bronchopulmonary, gastric, duodenal and pancreatic); patients with multiple neuroendocrine tumors associated with MEN1 syndrome will be eligible Patients must have radiographically measurable disease Pancreatic neuroendocrine patients must have had progression after prior therapy; patients with other foregut neuroendocrine tumors must have had progressive disease over the last 12 months, irrespective of prior therapy; patients with both functional (who may continue somatostatin analogues as required for control of related symptoms) and non-functional tumors are eligible; in patients who have previously received therapy, the number of prior lines of therapy should not be more than 2 lines of systemic therapy not including somatostatin analogues Written informed consent must be obtained prior to any screening procedures Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 A sufficient interval must have elapsed between the last dose of prior anti-cancer therapy (including cytotoxic and biological therapies and major surgery) and enrollment, to allow the effects of prior therapy to have abated: a) cytotoxic or targeted chemotherapy: greater than or equal to the duration of the cycle of the most recent treatment regimen (a minimum of 3 weeks for all regimens, except 6 weeks for nitrosoureas and mitomycin-C); b) biologic therapy (e.g., antibodies): greater than or equal to 4 weeks Absolute neutrophil count (ANC) greater than or equal to 1.5 x 10^9/L Hemoglobin (Hgb) greater than or equal to 9 g/dL Platelets greater than or equal to 100 x 10^9/L Serum total bilirubin less than or equal to 1.5 x upper limit of normal (ULN)  Patient has a known hypersensitivity to LEE011 or any of its excipients Patients with known or suspected brain metastases; however, if radiation therapy and/or surgery has been completed and serial evaluation by computed tomography (CT) (with contrast enhancement) or magnetic resonance imaging (MRI) over a minimum of 3 months demonstrates the disease to be stable and if the patient remains asymptomatic, then the patient may be enrolled; such patients must have no need for treatment with steroids or anti-epileptic medications Patients with concurrent malignancies or malignancies within 3 years prior to starting study drug (with the exception of tumors common to a single genetic cancer syndrome, i.e. MEN1, MEN2, von Hippel-Lindau [vHL], tuberous sclerosis complex [TSC] etc., or adequately treated, basal cell skin cancer, squamous cell carcinoma, non-melanoma skin cancer or curatively resected cervical cancer) Patient is not able to swallow oral medication and/or has impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of the study drugs (e.g., ulcerative diseases, uncontrolled nausea, vomiting, diarrhea, malabsorption syndrome, or small bowel resection) Known diagnosis of human immunodeficiency virus (HIV) or hepatitis C (testing is not mandatory) Patient has any other concurrent severe and/or uncontrolled medical condition that would, in the investigator's judgment, contraindicate patient participation in the clinical study (e.g. chronic pancreatitis, chronic active hepatitis, etc.) Patient who has received radiotherapy within less than or equal to 4 weeks or limited field radiation for palliation within less than or equal to 2 weeks prior to starting study drug, and who has not recovered to grade 1 or better from related side effects of such therapy (exceptions alopecia) and/or in whom greater than or equal to 30% of the bone marrow was irradiated Patient has had major surgery within 14 days prior to starting study drug or has not recovered from major side effects (tumor biopsy is not considered as major surgery) Impaired cardiac function or clinically significant cardiac diseases, including any of the following: a) history of acute coronary syndromes (including myocardial infarction, unstable angina, coronary artery bypass grafting, coronary angioplasty, or stenting) or symptomatic pericarditis less than 12 months prior to screening b) history of documented congestive heart failure (New York Heart Association functional classification III-IV) c) documented cardiomyopathy d) patient has a left ventricular ejection fraction (LVEF) less than 50% as determined by multiple gated acquisition (MUGA) scan or echocardiogram (ECHO) at screening e) history of ventricular, supraventricular, nodal arrhythmias, or any other cardiac arrhythmias, long QT syndrome or conduction abnormality within 12 months prior to starting study drug f) congenital long QT syndrome or a family history of corrected QT interval (QTc) prolongation g) on screening, inability to determine the corrected QT for Fridericia (QTcF) interval on the electrocardiogram (ECG) (i.e.: unreadable or not interpretable) or QTcF > 450 msec (using Fridericia's correction); all as determined by screening ECG (mean of triplicate ECGs) Systolic blood pressure greater than 160 mmHg or less than 90 mmHg at screening