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

PURPOSE: Phase I trial to study the effectiveness of specialized high-dose radiation therapy in treating patients who have stage I non-small cell lung cancer and lung dysfunction.

OBJECTIVES:

• Determine the maximum tolerated course of accelerated 3-dimensional conformal radiotherapy in patients with stage I non-small cell lung cancer with pulmonary dysfunction.
• Determine the short-term and long-term toxicity of this regimen in these patients.
• Determine local tumor control, failure-free survival, and overall survival in patients treated with this regimen.
• Determine the effect of radiotherapy dose volume relationships and pre-treatment pulmonary function studies on the incidence of pulmonary toxicity in these patients.

OUTLINE: This is a dose-escalation, multicenter study.

Patients receive accelerated 3-dimensional (3-D) conformal radiotherapy daily 5 days a week for 3.5-6 weeks.

Cohorts of 8 patients receive escalating fractions of accelerated 3-D conformal radiotherapy until the maximum tolerated course is determined. The maximum tolerated course is defined as the course at which no more than 2 patients develop at least grade 3 dose-limiting toxicity and no more than 1 patient develops at least grade 4 dose-limiting toxicity.

Patients are followed at 3 weeks, 6 weeks, 3 months, every 3 months for 2 years, and then every 6 months for 3 years.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed stage I (T1-2, N0) non-small cell lung cancer (NSCLC)

  • Squamous cell carcinoma
  • Basaloid carcinoma
  • Adenocarcinoma
  • Bronchoalveolar carcinoma
  • Adenosquamous carcinoma
  • Large cell carcinoma
  • Large cell neuroendocrine carcinoma
  • Giant cell carcinoma
  • Sarcomatoid carcinoma
  • Non-small cell carcinoma not otherwise specified

• Tridimensionally measurable solitary parenchymal lung lesion no greater than 4 cm in diameter by chest CT scan (lung windows)

• No metastatic disease or hilar or mediastinal lymphadenopathy

  • Must have mediastinoscopy* (anterior, cervical, or both) if mediastinal lymph nodes are greater than 1.0 cm in diameter by chest CT scan

    • No positive lymph nodes on mediastinoscopy* NOTE: *Patients may have positron-emission tomography in lieu of mediastinoscopy provided there is no fludeoxyglucose F 18 uptake in the mediastinum and hilum

• Poor surgical risk, as defined by 1 of the following:

  • High risk due to nonpulmonary reasons, such as renal failure, cardiac failure, or hepatic dysfunction and deemed by thoracic surgeon to be unsuitable for lobectomy

  • Pulmonary dysfunction indicated by one or more of the following:

    • FEV_1 less than 40% of predicted
    • DLCO less than 50% of predicted
    • Oxygen dependent
    • Chronic PaCO_2 greater than 45 mm Hg
    • VO_2 less than 15 mL/kg/min

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• 0-2

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception
• No weight loss of more than 10% within the past 6 months
• No other active (less than 30% risk of relapse after completion of prior therapy) malignancy except nonmelanoma skin cancer

Chemotherapy:

• No prior chemotherapy for NSCLC

Radiotherapy:

• No prior chest radiotherapy