Case Number : Case 1029 - 3rd June Posted By: Guest

? Atypical melanocyte proliferation within basal layer , ? Focal supra basal ascent... Or ? basal keratinocyte atypia? I think I will do Melan A first for this lesion...

This is not an easy case. I´m thinking there is some atypical keratinocytes at the basal layer with palisade Deep sections could show us a superficial CBC

Inspired by the comment of Dr Igor, may be the empty spaces are clue of BCC, mucinous artefacts !!!!!!

Difficult...not sure if the epidermal changes are significant or dermal!
Wondering about the nature of the superficial dermal vacuoles ?lymphatics ?pseudolipomatosis cutis

My first impression is superficial lymphatic malformation, aka lymphangioma circunscriptum, but the typical clinical presentation of grouped vesicle-like papules doesn’t fit on an impression of squamous cell carcinoma. I’m not sure about relevant epidermal abnormalities. Looking forward for new insights.

Bowen's ??

[size=4]Agree this is a challenge. I'd consider an unusual presentation of lichen aureus / pigmented purpura, or MF. As Igor suggested, the edge of an epidermal neoplasm such as BCC or SCC in situ, although the epidermis looks more reactive than neoplastic to me.[/size]

[size=4]The centrally atrophic epidermis looks like benign reactive inflammatory changes, with sparse lymphocyte exocytosis, spongiosis, hypergranulosis, hydropic changes, and compact hyperkeratosis. There is a lichenoid chronic inflammatory infiltrate (focally hyperchromatic lymphocytes, and more peripheral aggregates of plasma cells or lymphoplasmacytoid cells) with scattered clear, slightly refractile, oil-droplet-like, focally compartmented spaces with what appears to be foamy histiocyte (or adipocyte-like) vesiculated large pale nuclei at the periphery; these agree with this might represent adipose tissue, foreign-body oil, pseudolipomatosis vs.lymphangioma. There is subtle sparse brown pigment in the dermis, which may be non-specific melanin from inflammation, vs. hemosiderin [last photo]. [/size]

Mycosis fungoides.a typical variant.

I think this is superficial lymphangioma (lymphangioma circumscriptum). Sometimes, the epidermis overlying these lesions looks warty, which is true in our case and also explains the clinical presentation.

Lymphangiectasia.

What about lichen planus like keratosis?

I was all the time worried about the basal layer !!!!

I think we saw similar fat cells high in the dermis (anatomically located on the calf) last week in a "lichenoid keratosis" or regression reaction in a superficial BCC. Not sure I would put to much emphasis on them but fun to speculate.