Bronchioloalveolar carcinoma

Bronchioloalveolar carcinoma (BAC) is a rare type of lung cancer. It occurs more frequently among never-smokers, women and Asians.

By definition, BAC is not an invasive tumor. Therefore, pathologists classify it as a form of carcinoma in situ (CIS). However, unlike other forms of CIS, its behavior is malignant, often lethal. Major surgery, either a lobectomy or a pneumonectomy, is needed to control it, and recurrences are frequent. For this reason, oncologists classify it among the other malignant tumors, which are invasive tumors.

Classification
Bronchioloalveolar carcinoma is a sub-type of lung adenocarcinoma. However it is distinct from other lung adenocarcinomas by different clinical features, prognosis and response to treatment.