Inclusion Criteria:

- Female

- Diagnosis of adenocarcinoma of the lung

- Patient has had at least one core biopsy of her tumor

- Must be willing to undergo epidermal growth factor receptor (EGFR) mutation testing
of her tumor

- Stage IV or IIIB non-small cell lung cancer

- Non-smoker or former smoker. Non-smoker is defined as a person who smoked 100 or less
cigarettes in her lifetime while a former smoker is defined as a person who has quit
smoking one or more years ago.

- Three or more weeks since last radiation therapy

- Three or more weeks since last major surgery

- Must at least be able to walk and capable of taking care of herself although unable
to carry out work activities

- Life expectancy of 8 weeks or more

- Blood tests that show kidneys, liver and bone marrow to be working adequately

- Women of child-bearing potential must agree to use adequate contraception prior to
study entry and for the entire time enrolled in study

Exclusion Criteria:

- Prior exposure to Tarceva (OSI-774, erlotinib)

- Uncontrolled central nervous system problems

- Prior chemotherapy regimen

- Difficulty swallowing

- A disease or disorder that interferes with ability to digest and absorb food

- Incomplete healing of previous oncologic or other major surgery

- Significant medical history or unstable medical condition such as heart failure,
active infection, uncontrolled high blood pressure

- Pregnant or breast feeding

- A medical condition that could make it unsafe for patient to participate in this
study