Bronchoalveolar carcinoma is one of the four histologic subtypes of adenocarcinoma and its incidence is increasing. It grows in a lepidic fashion along the alveolar septa without invasive growth. The lack of invasive growth is an essential criterion based on data indicating that patients may be curable by surgical resection. The revised definition seems to be suitable for its solitary nodular form but less for multifocal or pneumonic-type form. High-resolution lung CT-scan is necessary to evaluate pulmonary involvement because of the high frequency of multifocal disease at initial presentation and because of the presence of ground glass opacity that could be one of the first manifestation of cancer bronchiolo-alvéolaireon CT. Therapeutic management does not differ from the one of non small cell lung cancer. Solitary nodules are treated by surgical resection with a good prognosis while multifocal and/or pneumonic forms are treated by systemic chemotherapy with a worse prognosis.