atypical adenomatous hyperplasia

Atypical adenomatous hyperplasia (AAH) of the lung is a putative precursor lesion of adenocarcinoma of the lung. This entity replaces part of a spectrum of the former bronchoalveolar carcinoma (BAC).

Pathology

AAHs are represented by localized small cell proliferation, usually measuring ≤0.5 cm, of mildly to moderately atypical type II pneumocytes and/or Clara cells that line along the alveolar walls, alveolar septae, or respiratory bronchiole . Subgrading of those lesions according to the spectrum of cellularity and atypia is not recommended .

Radiographic features 

Their radiographic appearances can be somewhat variable but have been commonly described as ground-glass nodules measuring less than 5 mm , opposed to adenocarcinomas in situ, which are also pre-invasive lesions, that tend to be larger.

Siehe auch:

• Milchglasherd
• In Situ Adenokarzinom der Lunge
• adenomatöse Hyperplasie Leber

und weiter:

• nichtkleinzelliges Lungenkarzinom