PRIMARY OBJECTIVES:
I. To evaluate the effect of dexamethasone (Dex) treatment in patients with relapsed non-small cell lung cancer (NSCLC) using 3'-fluorothymidine (FLT) positron emission tomography (PET) as measured by changes in tumor maximum standardized uptake value (SUVmax).
SECONDARY OBJECTIVES:
I. Assess the reversibility of Dex-mediated changes in tumor FLT retention following the withdrawal of Dex.
II. Measure tumor Glucocorticoid Receptor alpha expression (GRα) from recent patient biopsy samples.
III. Analyze blood samples obtained during imaging to determine serum Dex concentration and for senescence markers in circulating tumor cells.
OUTLINE:
Patients receive dexamethasone orally (PO) twice daily (BID) on days 1-5. Patients undergo 3 fluorothymidine F-18 (18F)-FLT PET scans. One scan within 7 days prior to the start of dexamethasone, one scan on day 3 after the 5th dose of dexamethasone, and one scan 6-9 days after the last dose of dexamethasone.
