Vulva
Benign skin adnexal tumors
Eccrine spiradenoma

Author: Nicole Riddle, M.D. (see Authors page)

Revised: 13 February 2016, last major update February 2016

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Eccrine spiradenoma [title] vulva
Cite this page: Eccrine spiradenoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/vulvaeccrinespiradenoma.html. Accessed April 24th, 2017.
Definition / General
  • Benign adnexal tumor with eccrine differentiation, may be derived from the secretory coil
  • See also topic in Skin-nonmelanocytic tumor chapter
Essential Features
  • Solitary, painful, slowly growing, pink-gray lesion, often > 1cm
  • Well circumscribed, round / oval cell nests ("blue balls") in dermis or subcutaneous tissue
  • Small basaloid cells on the outside and larger polygonal cells with vesicular nuclei and prominent nucleoli towards the center
Terminology
  • Also known as spiradenoma
Epidemiology
  • Rare in vulva
  • Commonly during reproductive age
Sites
  • Trunk > Scalp
  • Genital area rare (clitoris, labia majora)
Etiology
  • May be associated with CTNNB1 or CYLD gene mutations (Brooke-Speigler syndrome)
Clinical Features
  • Painful, slow growing mobile nodule. treated by excision
  • Rarely linear, zosteriform or Blaschko line type configuration
  • Malignant transformation: rapid growth, ulceration, discoloration
Prognostic Factors
  • Excellent prognosis (benign lesion), unless malignant transformation
Case Reports
Clinical Images

Images hosted on PathOut server:

Missing Image

Breast skin



Image hosted on Other server:

Missing Image

Scalp

Gross Description
  • Pink–gray or tan nodule, usually solitary
Micro Description
  • Well circumscribed, round-oval cell nests ("blue balls") in dermis or subcutaneous
  • Closely packed basaloid cells in organoid arrangement – more polygonal in center
  • Delicate fibrovascular capsule
  • No epidermal connection
  • May see ductal structures or squamoid areas
  • Lymphocytes common throughout lesion
  • Dilated intervening vessels may occur, sometimes so marked as to mimic vascular tumor
  • Cystic degeneration may occur
  • Malignant transformation: highly atypical cells, infiltrating, with numerous mitoses; sarcomatous features may be seen; often residual benign spiradenoma present
Micro Images

Images hosted on Other servers (site unspecified):

Missing Image Missing Image

Basophillic cells

Missing Image

Two tumor cell types

Missing Image

Prominent, dilated vessels

Missing Image Missing Image

Interspersed lymphocytes

Missing Image

Edematous change

Missing Image

Thin, fibrous capsule

Missing Image

Duct-like structures

Missing Image

PAS+

Missing Image

CK+

Cytology Description
  • Small cells with scant cytoplasm, hyperchromatic nuclei, no or minimal atypia, very rare mitoses
Cytology Images

Images hosted on Other servers:

Missing Image Missing Image

Images courtesy of Nicole Riddle, M.D.

Positive Stains
Differential Diagnosis
  • Cylindroma: small islands of tumor cells with 'jigsaw puzzle' pattern; thick, eosinophilic, material around cell clusters
Additional References