atypical adenomatous hyperplasia
atypical adenomatous hyperplasia
Pathology lungA term of art for what is essentially dysplassia of type-II cells in the lungs, which corresponds to a small but prominent focus of plump cells lining the air spaces. AAH is often an incidental finding in lungs resected for carcinoma, characterised by firm, 1–5-mm diameter white nodules surrounded by a polygon of interstitial fibrosis—hyperchromatic enlarged cuboidal eosinophilic pneumocytes which are neither papillary nor desquamate, sharply demarcated from surrounding lung. Some develop into bronchoalveolar carcinoma, a relatively indolent malignancy and essentially a carcinoma in situ of the lungs.
Pathology prostate
A localised proliferation of small (prostate) acini, which mimics prostate carcinoma, usually lacks cytological atypia, and has basal cells at the transition zone of the prostate. It is distinguished from well-differentiated CA by a relative lack of nuclear or nucleolar enlargement, infrequent crystalloids and a fragmented, but partially intact, basement membrane. AAH is more common in older patients with larger prostates, greater degree of nodular hyperplasia, more cancer and, if malignant, with higher Gleason scores.