RATIONALE: Studying samples of blood in the laboratory from patients undergoing treatment for non-small cell lung cancer may help doctors predict how patients will respond to treatment.

PURPOSE: This laboratory study is looking at proteomic patterns in stored blood samples from patients undergoing treatment for non-small cell lung cancer.

OBJECTIVES:

Primary

• To develop a serum proteomic classifier using matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry analysis of blood samples from patients with non-squamous cell non-small cell lung cancer to predict benefit, in terms of survival and time to progression, from treatment with bevacizumab in combination with carboplatin and paclitaxel.

Secondary

• To better quantitate candidate biomarkers by using more advanced mass spectrometric technologies, including multiple-reaction monitoring and heavy-labeled peptides.

OUTLINE: Previously collected pre-treatment samples of serum or plasma are randomly selected from patients enrolled on protocol ECOG-4599 (i.e., 60 from the bevacizumab arm and 30 from the control arm). Samples are analyzed by matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry to identify patterns from protein spectra that correlate with patient survival.

DISEASE CHARACTERISTICS:

• Available serum and plasma samples from patients with previously untreated locally advanced, metastatic, or recurrent non-squamous cell non-small cell lung cancer

• Enrolled on clinical trial ECOG-4599

  • Treated with carboplatin and paclitaxel with or without bevacizumab

PATIENT CHARACTERISTICS:

• Not specified

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

Samples submitted for research from patients participating in E4599