G-CSF and Pegfilgrastim in Treating Neutropenia in Patients Undergoing Radiation Therapy and Chemotherapy for Limited Stage Small Cell Lung Cancer

RATIONALE: Drugs used in chemotherapy, such as cisplatin and etoposide, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Radiation therapy uses high-energy x-rays to kill tumor cells. Colony-stimulating factors, such as G-CSF or pegfilgrastim, may increase the number of immune cells found in bone marrow or peripheral blood and may help the immune system recover from the side effects of chemotherapy and radiation therapy.

PURPOSE: This phase II trial is studying G-CSF and pegfilgrastim to see how well they work in treating neutropenia in patients undergoing combination chemotherapy and radiation therapy for limited stage small cell lung cancer.

OBJECTIVES:

Primary

* To evaluate the safety and efficacy of filgrastim (G-CSF) in reducing grade 4 neutropenia or grades 3-4 febrile neutropenia in patients with limited stage small cell lung cancer treated with radiotherapy and concurrent chemotherapy comprising cisplatin and etoposide.

Secondary

* To evaluate the safety and efficacy of pegfilgrastim in reducing grade 4 neutropenia or grades 3-4 febrile neutropenia in patients treated with adjuvant chemotherapy comprising cisplatin and etoposide.
* To estimate the incidence of dose modifications or treatment delays in patients treated with this regimen.
* To estimate the incidence of esophagitis, pneumonitis, and other non-hematological adverse events in patients treated with this regimen.
* To estimate the incidence of grade 4 thrombocytopenia in patients treated with this regimen.
* To estimate the median and two-year rate of progression-free and overall survival of patients treated with this regimen.

After completion of study therapy, patients are followed every 3 months for one year, every 6 months for 2-3 years, and then annually for up to 5 years.

Eligibility Criteria:
DISEASE CHARACTERISTICS:

* Histologically or cytologically confirmed small cell carcinoma of the lung

  * Limited stage disease, defined as any of the following:

    * Tumor confined to one hemithorax
    * T4 tumor not based on malignant pleural effusion
    * N3 disease not based on contralateral supraclavicular involvement
* No complete tumor resection
* Measurable or evaluable disease
* Pleural effusion allowed provided the following conditions are present:

  * Effusion is too small to tap under CT guidance and is not evident on chest x-ray
  * Effusion appears only after a thoracotomy or other invasive procedure
* Must have certification by a Radiation Oncologist that the tumor can be encompassed by limited radiotherapy fields without significantly compromising pulmonary function
* No distant metastases

PATIENT CHARACTERISTICS:

* Zubrod performance status 0-1
* ANC (absolute neutrophil count) ≥ 1,800 cells/mm³
* Platelet count ≥ 100,000 cells/mm³
* Hemoglobin ≥ 10.0 g/dL (transfusion or other intervention to achieve hemoglobin ≥ 8.0 g/dL allowed)
* Total bilirubin ≤ 1.5 mg/dL
* AST (aspartate aminotransferase) or ALT (alanine amino transferase ) ≤ 2 times the upper limit of normal (ULN)
* Alkaline phosphatase \< 2.5 times ULN (\< 5 times ULN if judged by the investigator to be related to liver metastases)
* Serum creatinine ≤ 1.5 mg/dL
* Creatinine clearance ≥ 50 mL/min
* FEV1 (Forced Expiratory Volume) obtained pre- or post-bronchodilator must be ≥ 1.5 liters/second
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception during and for ≥ 60 days after the last study treatment
* No prior invasive malignancy, except non-melanomatous skin cancer or other micro-invasive malignancy, or carcinoma in situ of the breast, oral cavity, or cervix, unless the patient has been disease-free for a minimum of 3 years
* No weight loss \> 5% for any reason within the past 3 months
* No severe, active comorbidity, defined as follows:

  * Unstable angina and/or congestive heart failure requiring hospitalization within the past 6 months
  * Transmural myocardial infarction within the past 6 months
  * Acute bacterial or fungal infection requiring intravenous antibiotics
  * Chronic Obstructive Pulmonary Disease exacerbation with FEV1 (forced expiratory volume) \< 1.5 liters/second or other respiratory illness requiring hospitalization or precluding study therapy within the past 30 days
  * Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects
  * AIDS (HIV testing not required for entry into this protocol)
* No prior allergic reaction to the study drugs

PRIOR CONCURRENT THERAPY:

* No prior systemic chemotherapy for lung cancer

  * Prior chemotherapy for a different cancer is allowed, provided it was completed ≥ 5 years prior to registration
* No prior radiotherapy to the region of the study cancer that would result in overlap of radiotherapy fields
* No concurrent intensity-modulated radiotherapy
* No concurrent amifostine