• Acute and late toxicity (with identification of predictive factors of toxicity) [ Designated as safety issue: Yes ]
• Local control [ Designated as safety issue: No ]
• Patterns of recurrence [ Designated as safety issue: No ]
• Overall survival (OS) [ Designated as safety issue: No ]
• Second cancers [ Designated as safety issue: No ]
• Prognostic and predictive factors of treatment effect on DFS and OS [ Designated as safety issue: No ]
• Cost per recurrence-free year of life [ Designated as safety issue: No ]

• Acute and late toxicity (with identification of predictive factors of toxicity)
• Local control
• Patterns of recurrence
• Overall survival (OS)
• Second cancers
• Prognostic and predictive factors of DFS and OS
• Cost per recurrence-free year of life

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. Giving radiation therapy after surgery may kill any tumor cells that remain after surgery. It is not yet known whether giving radiation therapy after surgery is more effective than no radiation therapy in treating patients with non-small cell lung cancer.

PURPOSE: This randomized phase III trial is studying radiation therapy to see how well it works compared to no radiation therapy in treating patients with non-small cell lung cancer that has been completely removed by surgery.

OBJECTIVES:

Primary

• Compare the disease-free survival of patients with completely resected non-small cell lung cancer treated with conformal thoracic radiotherapy vs no radiotherapy.

Secondary

• Determine the toxicity, in particular cardiac and pulmonary toxicity, of these regimens in these patients.
• Compare the local control in patients treated with these regimens.
• Determine patterns of recurrence in patients treated with these regimens.
• Determine the overall survival of patients treated with these regimens.
• Assess second cancers in patients treated with these regimens.
• Assess prognostic factors and predictive factors of treatment effect on disease-free survival and overall survival of patients treated with these regimens.
• Determine the cost per recurrence-free year of life.

OUTLINE: This is a multicenter, randomized study.

Patients are stratified according to participating center, prior chemotherapy (neoadjuvant alone vs adjuvant vs none), number of lymph nodes involved (0 vs 1 vs ≥ 2), histology (squamous cell vs other), and use of pretreatment positron emission tomography scans (yes vs no). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Beginning within 4-8 weeks after surgery or 2-4 weeks after chemotherapy, patients undergo adjuvant thoracic conformal radiotherapy once daily, 5 days per week, for 6 weeks.
• Arm II: Patients do not undergo adjuvant thoracic radiotherapy. After completion of study therapy, patients are followed periodically for up to10 years.

PROJECTED ACCRUAL: A total of 700 patients will be accrued for this study.

• Procedure: adjuvant therapy
• Procedure: observation
• Radiation: 3-dimensional conformal radiation therapy

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed non-small cell lung cancer

  • N2 mediastinal nodal involvement prior to neoadjuvant chemotherapy OR at the time of surgery in the absence of neoadjuvant chemotherapy

• Completely resected disease by lobectomy, bilobectomy, or pneumonectomy (absence of positive margins or extracapsular extension in a node removed separately)

  • Has undergone mediastinal lymph node exploration (lymph node sampling or complete dissection of lymph nodes at levels 4, 7, and 10 in case of right-sided thoracotomy and at levels 4 [if accessible], 5, 6, 7, and 10 in case of left-sided thoracotomy)
• No documented metastases
• No major pleural or pericardial effusion
• No synchronous contralateral lung cancer
• No clinical progression during post-operative chemotherapy

PATIENT CHARACTERISTICS:

• Not pregnant or nursing
• Fertile patients must use effective contraception
• WHO performance status 0-1
• Post-operative FEV_1 > 1 L (or > 35% theoretical value, PO_2 ≥ 70 mm Hg, and PCO_2 < 45 mm Hg)

• No severe cardiac disease within the past 6 months, including the following:

  • Arrhythmia
  • Congestive heart failure
  • Infarction
  • Pacemaker
• No severe pulmonary disease within the past 6 months
• No weight loss ≥ 10% within the 6 months before surgery
• No other prior or concurrent neoplasm, except for basal cell carcinoma of the skin or carcinoma in situ of the cervix
• No severe or uncontrolled systemic disease
• No familial, social, geographic, or psychological conditions that would preclude study participation

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• Prior chemotherapy allowed (neoadjuvant and/or adjuvant chemotherapy)
• No prior chest radiotherapy
• No concurrent chemotherapy during radiotherapy