Temsirolimus in Treating Patients With Locally Advanced or Metastatic Breast Cancer

PRIMARY OBJECTIVES: I. To determine the overall activity (as defined by complete response \[CR\] + partial response \[PR\] + stable disease \[SD\] for \>= 24 weeks) of a weekly 25 mg intravenous dose of temsirolimus in patients with locally advanced or metastatic breast cancer. II. To compare the activity of temsirolimus in patients with locally advanced or metastatic breast cancer whose primary tumors have mutations in the PIK3CA or PTEN gene with those whose tumors do not have a mutation in the PIK3CA gene. III. To examine correlations between antitumor activity of temsirolimus and alterations in expression of genes in the PI3K pathway in primary tumor biopsy specimens. OUTLINE: Patients receive temsirolimus intravenously (IV) over 30 minutes weekly. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.