Skin nonmelanocytic tumor

Carcinoma (nonadnexal)

Adenosquamous carcinoma

Editorial Board Member: Sara C. Shalin, M.D., Ph.D.
Ghassan A. Tranesh, M.D.
Hong Qu, M.D.

Topic Completed: 1 January 2015

Minor changes: 14 October 2020

Copyright: 2002-2022,, Inc.

PubMed Search: Adenosquamous carcinoma [title] skin

Ghassan A. Tranesh, M.D.
Hong Qu, M.D.
Page views in 2021: 4,503
Page views in 2022 to date: 308
Cite this page: Tranesh, G. Adenosquamous carcinoma. website. Accessed January 23rd, 2022.
Definition / general
  • Frequent confusion in the literature regarding this entity in the head and neck and high grade mucoepidermoid carcinoma (Int J Clin Exp Pathol 2014;7:1809)
  • More common in organs where adenocarcinoma arises frequently, including stomach, intestines and uterus (Oncol Lett 2014;7:1941)
Pathophysiology / etiology
  • Although its pathogenesis is largely unknown, 4 hypotheses have been proposed:
    1. Malignant transformation of both squamous and glandular-like cells originating from pleiotropic epithelial stem cells
    2. Tumorigenesis of squamous metaplasia in columnar epithelium
    3. Transdifferentiation of adenocarcinoma to squamous cell carcinoma
    4. Coexistence of both carcinomas (World J Surg Oncol 2013;11:124)
  • Neoplasm composed of an admixture or separate areas of squamous cell carcinoma and adenocarcinoma
  • Criteria for squamous cell carcinoma component are 2 or more of these features:
    • Intercellular bridging
    • Keratin pearl formation
    • Parakeratotic differentiation
    • Individual cell keratinization
    • Cellular arrangement showing a pavementing or mosaic pattern
  • Criterion for adenocarcinoma component is demonstration of intracytoplasmic mucin
  • World Health Organization Classification does not require intracytoplasmic mucin for diagnosis of adenocarcinoma in the presence of true glandular formation (Int J Clin Exp Pathol 2014;7:1809)
Case reports
  • Surgical excision or Mohs microsurgery are common treatment options (Head Neck Pathol 2011;5:108)
  • Locoregional recurrence is not uncommon
Clinical images

Images hosted on other servers:

Fig 3: recurrent tumor of shoulder

Various images

Gross description
  • White nodular infiltrate into subcutaneous tissue
Microscopic (histologic) description
  • Infiltrative islands of squamous cell carcinoma with admixed mucin-containing glandular structures, adenomatous changes and acinar formation
  • Glandular structures lined by low columnar epithelium, sometimes lined by an eosinophilic cuticle (ductular differentiation)
  • Perineural invasion relatively common (Arch Dermatol 2009;145:1152)
Microscopic (histologic) images

Images hosted on other servers:

Fig 1: infiltrative nests
and keratinizing
cysts are admixed with
glandular elements

Fig 2: CK903 (high molecular
weight keratin) stains the
tumor, CEA highlights
glandular differentiation

Positive stains
Differential diagnosis
Back to top
Image 01 Image 02