 Evaluation of response to systemic therapy is dependant on clinical and radiographic changes assessed prior to and after several cycles of systemic therapy. The response rate for lung cancer to systemic therapy ranges from 30 - 85, depending on histology and other clinical factors, but difficult to predict in individual patients. Spermine-spermidine acetyl transferase SSAT1 activity is up-regulated in many cancers and may be a marker of response to therapy. Metabolism of acetyl amantadine AA is reflective of SSAT1 activity. In order to determine if change in SSAT1 activity is predictive of response to systemic chemotherapy, we propose the following pilot clinical trial. A total of 20 volunteer patients - 10 patients with adenocarcinoma of the lung and 10 patients with small-cell histology will be included. Eligibility includes patients with adenocarcinoma and small-cell lung cancer who are at AJCC stage III or IV at diagnosis. Volunteers will be informed that this study is examining the possibility that we can detect a therapeutic response by a change in their excretion of AA before it can be detected by conventional patient assessment methods. The chemotherapy regimen will be selected by the treating physician and will not be influenced by participation in this clinical trial. The usual treatment regimen for the entities described above is a platinum-based doublet, often cis-platin with etoposide or gemcitabine administered for 4 to 6 cycles. The therapeutic response rates with these drug regimens is about 40 for adenocarcinoma and 70 for small-cell carcinoma. Clinical response is usually assessed between the second and third cycles of chemotherapy. 