Case Number : Case 2298 - 4 April 2019 Posted By: Raul Perret

Epithelioid hemangioma

Epithelioid hemangioma

I'm not sure if those are vascular spaces.

What about Langerhans Cell Histiocytosis

Cutaneous epithelioid angiomatous nodule- which has more solid areas of epithelioid endothelial cells and less conspicuous vessels. CEAN is considered a distinct lesion or related lesion in the spectrum of epithelioid hemangioma/ALHE

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12 hours ago, Alex-Ventura-Leon said:

I'm not sure if those are vascular spaces.

What about Langerhans Cell Histiocytosis

Agree...it could be a pulmonary lesion, we don't know CPC. So my first spot is LCH.

Really interesting. So is a Pseudomyogenic Hemangioendothelioma.

I am envious of Raul. He has all the good immunos.

This lesion clearly show vascular formation, even highlighted by CD31. I think pseudomyogenic hemangioendothelioma, despite the name, usually does not really form vascular channels. I think a subset of epithelioid hemangioma harbors a translocation involving FOSB gene, although with a different partner. I can't keep track with all these translocations but I have learned a lot from Raul. 

I'm learning a lot from Raul, too, about these new entry in molecular diagnostic tools. So, if FOSB positivity is in keeping also with epithelioid hemangioma, I favor this one. 

Found this interesting art : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4229947/

Dear all, 

As most of you proposed, I signed this case out as Epithelioid Hemangioma. Although most histological features were typical, this case also showed necrosis (not shown) and an unusually large size (5 cm). Taking into account these facts, I performed FOSb in order to confirm the diagnosis (diffuse and strong staining is seen in around 50-60% of EH based on some series) and rule out other mimickers like epithelioid angiosarcoma and epithelioid hemangioendothelioma that are FOSb negative. It is important to note that even though I favoured the dx on microbiopsy, I suggested a surgical excision due to the atypical features aforementioned.

Ps. Pseudomyogenic hemangioendothelioma is also positive for FOSb but morphology is completely different.