atypical squamous metaplasia
atypical squamous metaplasiaA metaplasia seen on various epithelial surfaces which have been subjected to ongoing “insults” that differ from the milieu to which those epithelia are usually exposed.
ASM, tracheobronchial mucosa Often associated with cigarette smoking and an increased risk of cancer. ASM may also be associated with fungal infections and granulomatous disease.
ASM, uterine cervix Heterogeneous group of lesions, up to two-thirds of which contain HPV. It is a difficult diagnosis to make, given that the nuclei are very subtly abnormal and even less abnormal than even mild (immature) metaplastic dysplasia. As in squamous atypia, the nuclei are enlarged into the range of 70–120 µm. The nuclear membranes are smooth or only slightly irregular, and the chromatin is fine and evenly distributed, without granularity.