ABSTRACTStage I non-small cell lung cancer (NSCLC) is a localized disease without metastasis; therefore, it can be treated effectively with local therapies. Pulmonary resection is the most frequent treatment, performed as pulmonary wedge resection, segmentectomy, lobectomy, or pneumonectomy. Some retrospective clinical studies of pulmonary wedge resection suggest that its outcome may be inferior to that of anatomical pulmonary resection, whereas other recent studies, which assess surgical margin status, leveled acceptable outcomes. Since the outcome of pulmonary wedge resection for lung cancer may depend on tumor size, distance from the surgical margin to the tumor, tumor size/margin distance ratio, and margin cytology results, a prospective study assessing these parameters is ongoing. This will allow us to identify the clinical implications of these factors and predict which patients are likely to have a good outcome.