trichoepithelioma

Definition : Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma.

Images

 Trichoepithelioma

• https://twitter.com/RyanHickMD/status/720951675310047232
• https://twitter.com/mariaramir/status/714933405629198340
• https://twitter.com/JMGardnerMD/status/599210445744943104
• https://twitter.com/JMGardnerMD/status/599200913853587458
• https://twitter.com/juanbarcia/status/566378732622209024
• https://twitter.com/TheSagePatel/status/529712828757061632
• https://twitter.com/drshahinhameed/status/742390802496684033

 stroma-stroma retraction in trichoepithelioma

• https://twitter.com/RyanneMDMBA/status/673310047049408512

 small trichoepithelioma

• https://twitter.com/ASDPTweets/status/733642848189489153

 desmoplastic trichoepithelioma : cords/nests basaloid cells, sclerotic stroma, horn cysts with keratin

• https://twitter.com/mariaramir/status/714933005920378882
• https://twitter.com/JMGardnerMD/status/539428205296640000

 Trichoepithelioma CK20+ Merkel cells (usually absent in BCC)

• https://twitter.com/DermpathMGH/status/745579787800952832

 Stromal hyaline droplets in a trichoepithelioma

• https://twitter.com/RikiSotillo/status/854307415000588288

Synopsis

 multilobular basaloid tumor
 palisaded nuclei
 fibrocellular stroma.

Differential diagnosis

 basal cell carcinoma (BCC)

• In Trichoepithelioma: CK20+ Merkel cells (usually absent in BCC)
• https://twitter.com/DermpathMGH/status/745579787800952832

Digital cases

 UI:910 - Trichoepithelioma

See also

 cutaenous tumors

References

 Diagnostic utility of immunohistochemistry in distinguishing trichoepithelioma and basal cell carcinoma: evaluation using tissue microarray samples. Tebcherani AJ, de Andrade HF Jr, Sotto MN. Mod Pathol. 2012 Jun 8. PMID: 22684216