Blue naevus

Case 326   Sept 2011 (P. McKee)  M 31  brown lump hip 

Only high power views.  Thought could be part of Bednar tumour, but no real cytological atypicality.  Pigment more melanin than haemosiderin for aneurysmal DF. 

Case 566  9.8.12 (C. Fletcher/P. McKee)  no clinical detail – grossly pigmented epithelioid form 

Three views only.  Extreme melanisation obscures cellular detail.  However, apparently no pleomorphism, macronucleoli or mitoses. 

Case 786   21.6.13 (R. Carr)  F 16 foot ? Spitz 

“Hypopigmented” BN.  S100-ve (common in BN); Melan-A +ve (dendritic pattern) 

S100 looked +ve to me, but in comparison to epidermal Langerhans’ cells it was considered –ve. 

DD: "cellular" neurothekeoma - do CD63, D2-40, and NSE. 

Case 1149  18.11.14  (U. Sundram)  F 24 rapidly enlarging pigmented lesion hand ?malignant 

Superficial typical blue naevus.  Deeper cellular/epithelioid blue naevus/melanocytoma.  Seemed to cause some diagnostic concern amongst commentators. 

Case 1552  7.6.16  (U. Sundram)  F 29 pigmented lesion buttock 

Called cellular, but I don’t think so.  Both BN and DPN can show periadnexal spread as here. 

Case 2387  22.8.19  (L. Yu)  M 16 foot 

Case 2138  20.8.18 (L. Yu)  F 20 scalp – some suggested cellular, but not really.