Case Number : Case 2832- 14 May 2021 Posted By: Dr. Richard Carr

Kamino’s bodies. Maturation. Epidermal rete ridge hyperplasia. The mitosis are probably superficial and near the epidermal rete ridge. A challenging case. 

Favor an AST, but I’m not able to rule out nevoid melanoma. 

Atypical spitzoid. Difficult to say benign or melanoma. 

Agree not an easy case. We favoured SSMM with some Reed-like features. I thought these were mainly colloid bodies rather than the typical pale pink Kamino bodies. Quite a compact naevoid dermal component with variation in morphology and up to 5 mitoses /mm2. p16 is the IHC and it's a complete null in the lesion is a great concern with the other features mentioned. BRAF IHC can be useful in such cases to exclude Spitz lesion but I was not happy to call this a Spitz tumour.

On 17/05/2021 at 15:31, Dr. Richard Carr said:

BRAF IHC can be useful in such cases to exclude Spitz lesion but I was not happy to call this a Spitz tumour.

Can I ask if PRAME immunostain of some help in such cases?

It should be helpful yes.