Squamous metaplasia
Bronchial squamous metaplasia. H&E stain. (WC/Yale Rosen)
Squamous metaplasia, abbreviated SM, is a benign transformation of an epithelium to a squamous morphology.
Immature squamous metaplasia is important to recognize, as it can histologically mimic high-grade squamous intraepithelial lesion (HSIL).
It is seen in a number of contexts - including:
- Squamous metaplasia of the uterine cervix.
- Squamous metaplasia of the urinary bladder.
- Squamous metaplasia of lactiferous ducts (SMOLD).
- Squamous metaplasia of the amnion.
- Squamous metaplasia of the endometrium.[1]
- Squamous metaplasia of the bronchial epithelium.
- Squamous metaplasia of the anus.