A Pharmacokinetic Study of Erlotinib in Cancer Patients With Advanced Solid Tumors, With Adequate and Moderately Impaired Hepatic Function

Inclusion Criteria: * Histologically confirmed advanced solid tumor (measurable or nonmeasurable) that is potentially responsive to erlotinib or for which no effective therapy is available, * Cohort 1: Adequate hepatic function: bilirubin \<= ULN, ALT (SGPT) and AST (SGOT) \<= 1.5 x ULN or Cohort 2: Moderate hepatic function: 7-9 as assessed by the Child-Pugh System, ECOG Performance Status 0-2 * Life expectancy \>= 12 weeks, * Prior radiation permitted provided that 4 weeks (or 2 weeks for palliative radiation) has elapsed and patients have recovered from acute toxic effects of radiotherapy, * Prior chemotherapy permitted provided that 4 weeks has elapsed and patients have recovered from acute toxic effects of chemotherapy, * Adequate hematopoietic and renal function: ANC \>= 1.5 x 10\^9/L, platelets \>= 75 x 10\^9/L, and creatinine \<= 1.5 x ULN, Exclusion Criteria: * Use of tobacco or nicotine-containing products within 4 weeks of Day 1 and while on study, * Use of a CYP3A4 inhibitor or inducer within 14 days prior to Day 1 and until Day 5, * Use of a warfarin-derivative anticoagulant within 14 days prior to Day 1 and until Day 5, * Encephalopathy \>= grade 2, * Significant history of cardiac disease unless well-controlled, * Active or uncontrolled infections or serious illnesses or medical conditions that could interfere with the patient's ongoing participation, * Concurrent anticancer therapy or any other investigational agents within 4 weeks of Day 1 and while on study, * Symptomatic brain metastases that are not stable, require steroids, are potentially life-threatening, or that have required radiation within the last 4 weeks, * Gastro-intestinal abnormalities, including inability to take oral medication, requirement for IV alimentation, active peptic ulcer or prior surgical procedures affecting absorption.