Everolimus in Treating Patients With Previously Treated Unresectable or Metastatic Esophageal Cancer or Stomach Cancer

Inclusion criteria: * Diagnosis of adenocarcinoma of the upper gastrointestinal tract * Metastatic or unresectable disease * Received 1-2 prior chemotherapy or biological therapy regimens for unresectable or metastatic disease * Measurable disease in ≥ 1 dimension by CT scan or MRI * Patients whose only measurable lesion is a metastatic lymph node are eligible provided they have permission from the principal investigator * ECOG performance status 0-1 * Life expectancy \> 3 months * ANC ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm\^3 * Hemoglobin ≥ 9 g/dL * Total bilirubin ≤ 1.5 times upper limit of normal (ULN) * AST and ALT ≤ 2.5 times ULN (≤ 5.0 times ULN if there is liver metastasis) * Creatinine clearance \> 60 mL/min * Fasting serum cholesterol \< 300 mg/dL or \< 7.75 mmol/L\* * Fasting triglycerides \< 2.5 times ULN\* * INR ≤ 3.5 (for patients on warfarin) * Negative pregnancy test * Fertile patients must use effective contraception during and for ≥ 4 months after completion of study treatment (oral, implantable, or injectable contraceptives are not considered effective contraception for this study) * More than 30 days since prior chemotherapy, surgery, radiotherapy, or investigational agents Exclusion Criteria: * uncontrolled diabetes mellitus, defined as fasting serum glucose \> 1.5 times ULN * severely impaired lung function * known HV infection * active, bleeding diathesis * unstable angina pectoris, symptomatic congestive heart failure, or myocardial infarction w…