dermal tumor with a grenz zone between the tumour and the
tumour islands in the dermis ;
May extend into the
Combination of solid
and cystic areas ;
Cystic spaces form as
a result of tumour cell degeneration ;
stroma varies from delicate vascularized fibrous tissue to
dense hyalinized collagen ;
connection may be present ;
Foci of squamous
differentiation and intracytoplasmic lumina ;
are often present which is of little prognostic significance.
Two types of cells
cell type is polyhedral with a rounded nucleus and slightly
basophilic cytoplasm. The second cell type is generally round with
Clear cell ; Poroid
; Oncocytic ; Epidermoid, and Pigmented.
Images of Clear cell Hidradenoma:
Images of Poroid Hidradenoma:
hidradenomas are characterized by prominent clear cells which is
present in less than one third of hidradenomas. Mucus producing
cells are found in some cases. The clear cells contain
glycogen and periodic acid-Schiff-positive, diastase-resistant
material, but no lipid.
hidradenomas are well circumscribed , non-encapsulated tumours
composed of predominantly poroid cells.
this variant resembles an eccrine poroma.
hidradenomas- cytological atypia or infiltrative margins; higher
rate of recurrence and malignancy.
The significance of atypical nuclear changes
in benign eccrine acrospiromas: a clinical and pathological study
of 18 cases.J
Cutan Pathol. 1984 Feb;11(1):35-44.