Pemetrexed, Carboplatin, and Bevacizumab as First-Line Therapy in Treating Older Patients With Stage IIIB or Stage IV Non-Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed nonsquamous cell non-small cell lung cancer (NSCLC) * Stage IIIB (with pleural effusion) or IV disease * Squamous cell carcinomas not allowed * Adenosquamous histology allowed * Clinically significant effusion (e.g., symptomatic pleural effusion or ascites) allowed provided it is drained before study treatment * No symptomatic pleural and/or peritoneal effusion (≥ grade 2 dyspnea, as defined by NCI CTCAE v3.0 criteria) that is not amenable to drainage * If effusion produces clinically significant measurable objective changes, such as hypoxia or estimated volume \> 500 mL, effusion should be drained even if asymptomatic * Measurable disease, defined as ≥ 1 lesion with longest diameter ≥ 2.0 cm by conventional techniques or ≥ 1.0 cm by spiral CT scan * If the sole site of disease is in a previously irradiated field, must have evidence of disease progression/recurrence within the irradiated field OR presence of a new lesion outside the irradiated field * No symptomatic, untreated, or uncontrolled CNS metastases * CNS metastases that were previously treated with whole brain radiotherapy (WBRT) allowed * Willing to enroll in NCCTG-N0392 PATIENT CHARACTERISTICS: * ECOG performance status 0-1 * Life expectancy ≥ 12 weeks * ANC ≥ 1,500/mm³ * Platelet count ≥ 100,000/mm³ * Hemoglobin ≥ 9 g/dL * Total bilirubin ≤ 1.5 times upper limit of normal (ULN) OR direct bilirubin normal * AST and ALT ≤ 3 times ULN (≤ 5 times ULN if liver has tumor involvement) * Creatinine clearance ≥ 45 mL/min * Not pregnant or nursing * Fertile patients must use effective contraception during and for 3 months after completion of study treatment * Able to take folic acid, vitamin B\_12 supplementation, or dexamethasone * Able to complete questionnaire(s) alone or with assistance * Willing to provide biologic specimens as required by the study * Willing to return to NCCTG participating center for follow-up * No clinically significant infection * No serious, nonhealing wounds, ulcers, or bone fractures * No seizure disorder * No second primary malignancy within the past 5 years, except for any of the following: * Carcinoma in situ of the cervix * Nonmelanomatous skin cancer * History of melanoma allowed only if diagnosed and definitively treated ≥ 5 years ago with no subsequent evidence of recurrence * Low-grade (Gleason score ≤ 6) localized prostate cancer (no nodal involvement) * Previously treated stage I breast cancer * No concurrent severe and/or uncontrolled medical condition, including any of the following: * Hypertension, labile hypertension, or history of poor compliance with antihypertensive medication * Angina pectoris * Congestive heart failure within the past 3 months, unless ejection fraction \> 40% * Myocardial infarction within the past 6 months * Cardiac arrhythmia * Diabetes mellitus * Interstitial pneumonia or extensive, symptomatic interstitial fibrosis of the lung * Active or recent history of hemoptysis \> ½ teaspoon per event * Ongoing or active infection * Psychiatric illness/social situation that would limit compliance with study requirements * No abdominal fistula, gastrointestinal perforation, or intra-abdominal abscess within the past 12 months * No diverticulitis within the past 12 months * No stroke within the past 6 months * No significant traumatic injury within the past 8 weeks * Not at greater than normal risk of bleeding PRIOR CONCURRENT THERAPY: * See Disease Characteristics * No prior radiotherapy to \> 25% of bone marrow * More than 2 weeks since prior radiotherapy and recovered (alopecia allowed) * At least 2 weeks since prior WBRT * At least 3 days since prior gamma knife radiosurgery (without WBRT) for brain metastases * More than 4 weeks since prior administration of live or attenuated viral vaccine * More than 8 weeks since prior major surgery (e.g., laparotomy) or open biopsy (\> 4 weeks since minor surgery) * Insertion of a vascular access device allowed * No prior chemotherapy or systemic therapy for advanced lung cancer, except neoadjuvant or adjuvant chemotherapy * No NSAID's 2 days prior to (5 days for long-acting NSAID's), the day of, and 2 days following protocol treatment * More than 12 months since prior neoadjuvant therapy, adjuvant therapy, systemic chemotherapy, chemoradiotherapy, immunotherapy, or biologic therapy * No concurrent anticoagulants * Low-dose warfarin or heparin for deep venous thrombosis prophylaxis allowed