The cytology of giant solitary trichoepithelioma

Abstract

Giant solitary trichoepithelioma (GST) is a rare trichogenic tumor, which may present as a pigmented lesion. An 80-year-old man was diagnosed to have giant solitary trichoepithelioma on fine-needle aspiration cytology. The cytological findings represented the histological features. The recognition of GST is important because of its close resemblance to basal cell carcinoma and other skin adnexal tumors - clinically, cytologically and histologically.

Keywords: FNAC; Giant solitary trichoepithelioma; basal cell carcinoma; microcystic adnexal carcinoma; trichoblastoma.

Figure 1

Smears showing frond-like pattern of basaloid epithelial cells(H and E; MGG, ×100)

Figure 2

Smear showing papillary mesenchymal body (H and E, ×100)

Figure 3

Smears showing uniform basaloid cells arranged as nests and adenoid pattern (H and E, ×400)

Figure 4

Microphotograph of FNAC smears showing abrupt keratinization (H and E, MGG ×400)

Figure 5

Smears showing melanin pigmentation (H and E ×400)

Figure 6

Section showing epithelial islands with follicular differentiation, fibrotic stroma is closely associated with epithelial islands, retraction artefact is absent (H and E, ×400)