RATIONALE: Learning about the effects of radiation therapy on the body's muscles, organs, and bones in patients with stage III non-small cell lung cancer may help doctors plan the best treatment.

PURPOSE: This clinical trial is studying the effects of radiation therapy on the body in patients with stage III non-small cell lung cancer.

OBJECTIVES:

Primary

• To determine energy and protein consumption on an average radiotherapy treatment day using the multiple pass method 24-hour analysis of food recall at baseline and treatment end.
• To compare energy and protein by mouth intake from baseline to treatment end.
• To measure and compare diet quality from baseline to radiotherapy treatment end by Healthy Eating Index (HEI) score.
• To determine lean body mass versus fat mass using a bioelectrical impedance analysis machine.
• To compare body fat to lean body mass percentage at baseline with that at radiotherapy treatment end.
• To correlate energy and protein consumption with lean body mass at baseline and treatment end.
• To determine the change in appetite throughout radiotherapy by comparing data obtained by interview at baseline and radiotherapy treatment end.
• To determine the change in performance level (Karnofsky percentage) associated with the radiotherapy through a series of questions asked at baseline and treatment end.

OUTLINE: Patients receive radiotherapy as planned for 7 weeks. Patients undergo an interview on treatment day 1 (before initiation of radiotherapy) and treatment day 35 (after completion of radiotherapy) regarding recent food consumption history and appetite. Patients' standing weight and height are measured on these days and their body composition, measured with a bioelectrical impedance analysis (BIA) device, are also taken. Patients' Karnofsky performance score are obtained from their medical record.

DISEASE CHARACTERISTICS:

• Diagnosed with stage III non-small cell lung cancer (NSCLC)

• Plan to begin radiotherapy for NSCLC

  • Radiotherapy is the only planned therapy for this cancer

• No brain metastases

PATIENT CHARACTERISTICS:

Inclusion criteria:

• Must be able to stand without assistance

Exclusion criteria:

• Unable to comply with study requirements
• Native language other than American English
• Pacemaker or implanted defibrillator

PRIOR CONCURRENT THERAPY:

Exclusion criteria:

• Receiving chemotherapy in combination with radiotherapy
• Concurrent megace or steroids

Primary care center