Adenocarcinoma in situ

In situ pulmonary adenocarcinoma (AIS)—previously included in the category of "bronchioloalveolar carcinoma" (BAC)—is a subtype of lung adenocarcinoma. It tends to arise in the distal bronchioles or alveoli and is defined by a non-invasive growth pattern. [Source: Wikipedia ]

Synonyms
Bronchiolo-alveolar carcinoma