Gemcitabine and Carboplatin Followed by Paclitaxel in Treating Patients With Stage III or Stage IV Non-Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically confirmed non-small lung cancer (NSCLC) of any of the following histologic types: * Squamous cell * Adenocarcinoma * Large cell carcinoma * Unspecified * Evidence of at least 1 of the following criteria: * Newly diagnosed inoperable stage IIIB (pleural effusion) disease * Patients with stage III disease who are unable to undergo combined modality therapy * Stage IV disease * Recurrent non-small cell lung cancer regardless of site * Diagnosis based on sputum cytology acceptable if confirmed by an independent pathologic review * Patients must have measurable or evaluable disease * Measurable or evaluable disease must be outside the previous radiation field or a new lesion must be present * Patients with brain metastases are eligible, provided they are either asymptomatic (no neurological symptoms or signs, no evidence of midline shift), or controlled (i.e., after surgical resection or radiotherapy/radiosurgery), and off all steroid therapy for at least two weeks with no evidence of progression by symptoms or radiologic imaging PATIENT CHARACTERISTICS: * ECOG performance status of 2 or 3 OR HIV-positive OR underwent prior status post organ transplantation * No active serious infection (except for HIV infection) * No symptomatic, untreated malignant pericardial effusion * No congestive heart failure * No other serious underlying medical condition that would otherwise impair their ability to receive protocol treatment * Absolute granulocyte count ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm \^3 * Creatinine clearance ≥ 40 mL/min * Creatinine ≤ 1.8 mg/dL * Bilirubin \< 1.5 mg/dL * SGOT ≤ 2 times upper limit of normal * Not pregnant or nursing * Negative pregnancy test * Males or females of reproductive potential may not participate unless they have agreed to use effective barrier contraceptive methods * No prior malignancy within the past 5 years except for adequately treated basal cell or squamous cell skin cancer or carcinoma in situ of the cervix PRIOR CONCURRENT THERAPY: * See Disease Characteristics * Prior chemotherapy is not allowed * At least three weeks since prior radiotherapy and recovered from all toxicities * At least three weeks must have elapsed from major surgery and recovered from all adverse effects of surgery * No prior colony-stimulating factors or interferon * No concurrent hormonal, biologic, or radiotherapy to measurable lesions * Patients may receive concurrent palliative radiotherapy to small-field nonmeasurable sites of disease (e.g., painful bony metastases)