Histomorphological and Immunohistochemical Reappraisal of Cutaneous Adnexal Tumours: A Hospital Based Study

Table 7

Salient histopathological features of follicular tumours.

Proliferating trichilemmal tumour	(i) Tumour lobules of squamous epithelium; (ii) Epithelium in centre abruptly changed into amorphous keratin; (iii) Epidermoid keratinization resembling squamous eddies with nuclear atypia and individual cell keratinisation
Pilomatricoma	(i) Tumour made of epithelial islands in a cellular stroma, located in dermis containing two types of cells; (ii) Basophilic cells round to elongated; (iii) Shadow cells that had distinct border with loss of nucleus and calcification seen
Trichilemmoma	(i) Verrucous hyperplasia with lobular formations extending into the dermis; (ii) Many cells demonstrating clear cytoplasm (PAS positive)
Trichofolliculoma	(i) Keratin filled cysts lined by squamous epithelium; (ii) Numerous secondary (immature) hair follicles emanating from the cyst wall
Trichoepithelioma	(i) Superficial dermal lesion with prominent stroma; (ii) Horn cyst of variable sizes; (iii) Basaloid epithelial formations; (iv) No retraction artifact