Sirolimus in Treating Patients With Solid Tumors That Are Metastatic or Cannot Be Removed By Surgery

PRIMARY OBJECTIVES: I. To describe the magnitude, inter-individual variability and time course of sirolimus-induced changes in fasting serum glucose and triglycerides. SECONDARY OBJECTIVES: I. To assess candidate genetic variants for their correlation with changes in fasting glucose and/or triglycerides. II. To assess tumor response by the Response Evaluation Criteria In Solid Tumors (RECIST, version 1.1) and explore whether there is any correlation between response and changes in fasting glucose and/or triglycerides. III. To assess toxicity by the Common Terminology Criteria for Adverse Events (CTCAE, version 4.0) and explore whether there is any correlation between toxicities and changes in fasting glucose and/or triglycerides. IV. To quantify and determine the functional status of circulating regulatory T cells (Tregs) before and during treatment. OUTLINE: Patients receive sirolimus orally (PO) on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.