Case Number : Case 1478 -23 February Posted By: Guest

Epithelioid blue nevus. There´s a odd basophilic colagen that looks like solar elastosis. If this is a solar elastosos, maybe the age of the patient is wrong or the slides are from other patient. If this blue colagen in fact is not colagen, but a myxoid matrix, this may be an associated myxoma in the context of the Carney complex.

Cellular Blue naevus.

Agree with Igor's comment about solar elastosis.

Cellular blue naevus. Yes, the amount of solar elastosis is certainly odd for the age!

In an epithelioid blue nevus I would expect marked pigmented epithelioid melanocytes. I think this biphasic pattern, with nests of pale cells compartmentalized by septa rich in melanophages is more in keeping with a cellular blue nevus.

Agree with the blue nevus type of lesions, if someone called this either deep penetrating nevus or cellular blue nevus I would accept it, I think there is morphological support for either of these lesions. From my point of view it is myxoid change of the stroma that we see. Bothers me that the deep limits are compromised....

epithelioid blue nevus

I see an entirely intradermal melanocytic lesion below an elastotic actinic wrap, with two cellular populations: one with non nested heavy pigmented spindle or round cells; and the other with nested less pigmented, epithelioid melanocytes with clear large cytoplasm. Some cell show a egg-fried appearance...I favor an  Epithelioid Blue Nevus.

Cellular blue nevus. I also found the blueish look of the dermis odd...

Hi everyone, for some reason the wrong history was uploaded. Here is the correct history:

74 year old man with a pigmented lesion of the left nose clinically thought to be a blue nevus. I'll leave it up for one more day to see if anyone has any new thoughts before posting our diagnosis.

My apologies for the tardy update--bad winter storm in Michigan has everyone going crazy!

I was thinking DPN on the original history (I was not sure it was elastosis or mucin!) now I want to see a melanA to rule out lentigo maligna. I would express a some uncertainty and have it fully excised.  Did not think it had the classical cytology of epithelioid blue / pigmented epithelioid melanocytoma / pigment synthesising melanoma / low grade hypermelanotic dermal melanoma etc. so I would probably say DPN-like lesion of uncertain malignant potential but favouring benign behaviour.

Given the age of the patient, we too were very cautious about the diagnosis. Our final diagnosis was atypical melanocytic proliferation with deep penetrating nevus-like features; we asked that the lesion be fully excised. No residual was present on the re-excision and the patient is currently being followed. We did not do any further stains as the biopsy was very small.