Case Number : Case 2497 - 31 January 2020 Posted By: Dr. Richard Carr

Angiosarcoma.

 Of course epithelioid angiosarcoma is a possibility but some images make me also consider recurrent Hodgkin (cutaneous Hodgkin?). Awaiting IHC.

angiosarcoma

Looks epitheioid angiosarcoma. But waiting for the trick and immunos! 

This is a challenging and controversial case.

Reported initially as a fibrohistiocytic lesion in keeping with an aneurysmal fibrous histiocytoma (CD34 negative, also negative for PanK, SMA, S100, MelanA with scattered macrophages. No other vascular markers performed.

I was asked to review a small dermal local recurrence at two years  which showed widespread CD31 positive staining, CD34 neg.

My differential of this relatively small dermal based lesion including: epithelioid angiomatous nodule or epithelioid haemangioendothelioama (favoured).

Colleagues in Friedricshafen kindly reviewed the case (Thomas Mentzel) and opined this was epithelioid angiosarcoma (CAMTA1 and HHV8 negative, CD31 & ERG +ve). They were not happy with the presence of mitotic activity, some apoptosis.

I confess I was uncomfortable with the implication of a high grade angiosarcoma for such a small dermal tumour.

Raul Perret commented for me (on selected images) as follows: Dear Rick, Based on these images, I am personally in favour of an intermediate malignancy vascular tumor (rarely metastasizing) and would have suggested (as TM) complete excision and clinical follow-up. I thought of pseudomyogenic hemangioendothelioma and composite hemangioendothelioma but I confess morphology is not completely clear cut. Personally, I would have added FOSb immunohistochemistry (typically positive in pseudomyogenic hemangioendothelioma). It is important to remark that vascular tumors are one of the most difficult areas in Pathology so we can all commit mistakes. Hope I helped a little.  Big hug, Raul

Interestingly the case was subsequently reviewed by one of our National experts in the UK and they favoured epithelioid haemangioendothelioma.

I guess we learn from this that such cases are challenging and there is not necessarily agreement between experts.