Erlotinib in Treating Patients With Advanced Non-Small Cell Lung Cancer, Ovarian Cancer, or Squamous Cell Carcinoma of the Head and Neck

PRIMARY OBJECTIVES: I. To determine if a significant correlation exists between the length of the CA dinucleotide repeat polymorphism in the EGFR gene and observed toxicity in patients treated with OSI-774. SECONDARY OBJECTIVES: I. To study the pharmacodynamic effects of OSI-774 on EGFR activity and MAP kinase signaling using skin as a surrogate tissue. II. To determine if interindividual variation of OSI-774 pharmacokinetics is related to a previously described CYP3A5 genetic polymorphism. III. To evaluate whether toxicity or inhibition of EGFR phosphorylation correlates with OSI-774 AUC in patients treated with OSI-774. IV. To describe the observed anti-tumor response and toxicities in patients with advanced solid tumors treated with single agent fixed dose of OSI-774. OUTLINE: This is a multicenter study. Patients are stratified according to length of CA dinucleotide repeat polymorphism (short vs medium vs long). Patients receive oral erlotinib on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.