Phase II Trial of Enzastaurin Plus Carboplatin and Gemcitabine (ECoG) in Bevacizumab-Ineligible Patients and Enzastaurin Plus Carboplatin, Gemcitabine and Bevacizumab (B-ECoG) in Bevacizumab-Eligible Patients With Advanced Non-Small Cell Lung Cancer (NSCLC)

RATIONALE: Enzastaurin may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Drugs used in chemotherapy, such as carboplatin and gemcitabine, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Giving enzastaurin together with carboplatin and gemcitabine, with or without bevacizumab, may kill more tumor cells.

PURPOSE: This phase II trial is studying how well giving enzastaurin together with carboplatin and gemcitabine, with or without bevacizumab, works in treating patients with recurrent, stage IIIB, or stage IV non-small cell lung cancer.