Information about the epidemiology of AIS is limited, due to changes in definition of this disease and separation from BAC category. Under the new, more restrictive WHO criteria for lung cancer classification, AIS is now diagnosed much less frequently than it was in the past. Recent studies suggest that AIS comprises between 3% and 5% of all lung carcinomas in the U.S. Incidence The incidence of bronchiolo-alveolar carcinoma has been reported to vary from 4–24% of all lung cancer patients. An analysis of Surveillance epidemiology and End results registry ( SEER) by Read et al. revealed that although the incidence of BAC has increased over the past two decade it still constitutes less than 4% of NSCLC in every time interval. This difference in the incidence has been attributed to complex histopathology of cancer. While pure BAC is rare, the increase in incidence as seen in various studies can be due to unclear histological classification till WHO came up with its classification in 1999 and then in 2004. Another distinguishing feature about BAC is that it afflicts men and women in equal proportions, some recent studies even suggest slightly higher incidence among women.
Adenocarcinoma in situ of the lung
Epithelial-myoepithelial carcinoma of the lung
Salivary gland–like carcinoma of the lung
Minimally invasive adenocarcinoma of the lung
Sarcomatoid carcinoma of the lung
Mucinous cystadenocarcinoma of the lung
Adenocarcinoma of the lung
Pulmonary sclerosing pneumocytoma