RATIONALE: Specialized radiation therapy that delivers a high dose of radiation directly to the tumor over a shorter period of time may kill more tumor cells and cause less damage to normal tissue.

PURPOSE: This phase II trial is studying the side effects of hypofractionated 3-dimensional radiation therapy and to see how well it works in treating patients with newly diagnosed stage I, stage II, or stage III non-small cell lung cancer.

OBJECTIVES:

Primary

• To evaluate the acute and long-term radio-induced toxicity (any organ) of hypofractionated 3-dimensional conformal radiotherapy in patients with newly diagnosed stage I-III non-small cell lung cancer.

Secondary

• To assess the radiological tumor response rate at 3 months after completion of radiotherapy.
• To assess the actuarial freedom from thoracic progression rate.

OUTLINE: Patients are stratified according to combined lung volume at 25 Gy (≤ 30% vs > 30%). Patients are assigned to 1 of 3 treatment groups.

• Group 1: Patients undergo hypofractionated 3-dimensional conformal radiotherapy 5 days a week for 24 fractions (total of 72 Gy).
• Group 2: Patients undergo hypofractionated 3-dimensional conformal radiotherapy 5 days a week for 22 fractions (total of 66 Gy).
• Group 3: Patients undergo hypofractionated 3-dimensional conformal radiotherapy 5 days a week for 20 fractions (total of 60 Gy).

After completion of study treatment, patients are followed up every 3 months for 2 years and then every 6 months thereafter.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed newly diagnosed non-small cell lung cancer meeting 1 of the following stage criteria:

  • Stage I or II disease

    • Medically inoperable or patient refused surgery

  • Stage IIIA or IIIB disease (no pleural effusions)

• Radiation dose parameters must satisfy the required study dose-volume constraints

PATIENT CHARACTERISTICS:

• Karnofsky performance status 70-100%
• Weight loss ≤ 10% within 3 months before diagnosis
• No other malignancy within the past 5 years, except nonmelanoma skin cancer
• No clinically significant cardiovascular disease (e.g., hypertension [blood pressure > 150/100 mm Hg], myocardial infarction or stroke within the past 6 months, or unstable angina)

PRIOR CONCURRENT THERAPY:

• No concurrent chemotherapy