Hydradenoma Papilliferum (HP)

Epidemiology and Etiology:

·

Common sites:

· Restricted to:

· Eyelids

· Axillae

· Genitoperineal skin

Gross features:

· Nodular

· Bluish red

· Dermal lesion

· < 3 cm usually

·

Histologic features:

· Circumscribed

· Proliferation of large papillae within a cystic space within the dermis

· Smaller tubules may be seen at the periphery

· Cuboidal to low columnar epithelium with decapitation secretion

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

·

Other features:

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References:

· Silverberg SG, DeLellis RA, Frable WJ, LiVolsi VA, Wick MR. Silverberg's Principles and Practice of Surgical Pathology and Cytopathology: 2-Volume Set. 4th ed. Churchill Livingstone; 2005.