In hair germ tumors, hair follicle development is partially or complet
ely recapitulated. The trichoblastoma represents a purely epithelial t
umour within this group of tumours. We identified a trichoblastoma sho
wing exclusively adenocystic features in a 32 years old woman. This va
riant has been very rarely described in the literature. We review the
history of hair germ tumors and discuss the problems of their classifi
cation.