Hidradenoma Explained

Hidradenoma
Synonyms:	Acrospiroma, cystadenoma, hydrocystadenomas
Field:	Dermatology

Hidradenoma refers to a benign adnexal tumor of the apical sweat gland.^{[1] [2]} These are 1–3 cm translucent blue cystic nodules. It usually presents as a single, small skin-colored lesion, and may be considered closely related to or a variant of poromas.^[3] Hidradenomas are often sub-classified based on subtle histologic differences, for example:^[4]

• Eccrine acrospiroma
• Clear-cell hidradenoma or acrospiroma
• Nodular hidradenoma or acrospiroma
• Solid-cystic hidradenoma

Discussion of sweat gland tumors can be difficult and confusing due to the complex classification and redundant terminology used to describe the same tumors. For example, acrospiroma and hidradenoma are synonymous, and sometimes the term acrospiroma is used to generally describe benign sweat gland tumors. In addition, a single lesion may contain a mixture of cell-types. There has also been a change in understanding about how tumors that were previously believed to strictly derive from specific sweat gland types may, in fact, derive from both eccrine or apocrine glands.^{[5] [6]}

Hidradenomas are by definition benign, with malignant transformation very rare. When tumors show malignant characteristics, they are known as hidradenocarcinoma.^[7] Surgical excision is usually curative and local recurrences are rare, although malignant tumors may metastasize.

See also

• Spiroma
• List of cutaneous conditions
• List of cutaneous neoplasms associated with systemic syndromes

Notes and References

1. Laws RA, English JC, Elston DM . Acrospiroma: a case report and review . Cutis . 58 . 5 . 349–51 . November 1996 . 8934076 .
2. Obaidat NA, Alsaad KO, Ghazarian D . Skin adnexal neoplasms--part 2: an approach to tumours of cutaneous sweat glands . Journal of Clinical Pathology . 60 . 2 . 145–59 . February 2007 . 16882695 . 1860616 . 10.1136/jcp.2006.041608 .
3. Lim JS, Kwon ES, Myung KB, Cheong SH . Poroid Hidradenoma: A Two-Case Report and Literature Review . Annals of Dermatology . 33 . 3 . 289–292 . June 2021 . 34079192 . 8137338 . 10.5021/ad.2021.33.3.289 .
4. Al-Adawi SS, Al-Qasabi B, Al-Bahri M, Aljarrah A, Al-Aghbari S . Clear Cell Hidradenoma of the Breast Diagnosed on a Core Needle Biopsy: A case report and review of the literature . Sultan Qaboos University Medical Journal . 20 . 3 . e357–e361 . August 2020 . 33110653 . 7574794 . 10.18295/squmj.2020.20.03.017 .
5. Book: Rook's Textbook of Dermatology. 8th. John Wiley & Sons Ltd.. 2010. 978-1-4051-6169-5. Chichester, West Sussex. Griffiths. C. Cox. N. Breathnach. S. 3 . Burns. T . vanc . 53. Tumours of the Skin Appendages: Eccrine or aprocrine/follicular tumours.
6. Book: Rook's Textbook of Dermatology. 8th. John Wiley & Sons Ltd.. 2010. 978-1-4051-6169-5. Chichester, West Sussex. Griffiths. C. Cox. N. Breathnach. S. 3 . Burns. T . vanc . 53. Tumours of the Skin Appendages: Eccrine gland tumours.
7. Hernández-Pérez E, Cestoni-Parducci R . Nodular hidradenoma and hidradenocarcinoma. A 10-year review . Journal of the American Academy of Dermatology . 12 . 1 Pt 1 . 15–20 . 1985 . 2984259 . 10.1016/s0190-9622(85)70002-3 .