OBJECTIVES: I. Determine the objective response rate in elderly patients with stage IIIB or IV non-small cell lung cancer treated with oral vinorelbine. II. Determine the time to progression in patients treated with this drug. III. Determine the toxicity of this drug in these patients. IV. Determine whether there is a perceived preference for this oral administration in these patients. V. Determine the quality of life of these patients when treated with this drug. VI. Assess individual variation in responses, pharmacokinetic parameters, and/or biological correlates in patients treated with this drug.