Lung Adenocarcinoma In Situ

**Semantic type:** Neoplastic Process

**Definition:** A localized non-invasive adenocarcinoma of the lung measuring 3 cm or less. It is characterized by a pure lepidic growth pattern and the lack of stromal, vascular, or pleural invasion.

**Synonyms:** - Bronchioloalveolar Carcinoma - Lung AIS