Journal Club Summary:

Hair follicle “bulges” (der Wulst) are commonly seen in dermpath sections. How they differentiate from BCC – usually vertically oriented, surrounded by normal dermis, prominent basement membrane, no mitoses, no atypia and lack of myxoid stroma. Normal structure of hair follicles in the central facial skin.

PEH (Pseudoepitheliomatous hyperplasia) can be associated with many different types of lesions. Here is a nice summary table from @SGottesmanMD.

Most dermpathJC participants agree that verrucous carcinoma can be quite impossible to distinguish from pseudoepitheliomatous hyperplasia in certain scenarios. This is where additional clinical information may be helpful.

Pseuodsarcomatous fibroepithelial polyp – fatty core which shows pleomorphic lipoblast-like cells which have similarity to pleomorphic lipomas and some deep soft tissue sarcomas (liposracoma). These changes are thought to be of a degenerative nature. They are very rare as most dermpathJC participants have never seen such changes in fibroepithelial polyps. @JMGardnerMD is wondering if some of these are in the pleomorphic fibroma/lipoma spectrum, and would be cool to do RB1 on a specimen like this. Additional reading about loss of retinblastoma in pleomorphic fibroma: https://www.ncbi.nlm.nih.gov/m/pubmed/28543636/

Acroangiodermatitis of Mali aka dermatitis hemostatica aka Bluefarb-Stewart syndrome aka pseudo-Kaposi sarcoma. Here’s another useful table from @SGottesmanMD.

Reactive angioendotheliomatosis (term used in several different ways and is still confusing to most participants)

• Reactive vascular proliferation
• Reactive histiocytes proliferation filling dilated vessels

And last but not least, basaloid, follicular and sebaceous induction over a dermatofibroma. Photos by @JMGardnerMD, @SGottesmanMD and @KUSAURAP

Hope you have a happy New Year and we will see you January 24th, 2019 at 9pm EST for another exciting dermpath journal club.

Kind regards,

Silvija Gottesman, MD