OUTLINE: This is a dose escalation study. Patients are stratified by the percentage of total lung volume (TLV) receiving greater than 20 Gy of radiation (less than 25% vs 25% to less than 37% vs at least 37%). As of 7/1/1999, the third stratum closed to accrual. Patients receive 3-dimensional conformal radiotherapy (3D-CRT) 5 days a week for either 6-7 weeks, 7-8 weeks, or 9-10 weeks (depending on the cohort). Within each TLV stratum, cohorts of 15-36 patients receive escalating doses of 3D-CRT until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which less than 15% of patients experience dose limiting toxicity. Patients are followed every 3 months for 1 year, every 4 months for 1 year, every 6 months for 3 years, and then annually thereafter.