Case Number : Case 2784- 9 March 2021 Posted By: Iskander H. Chaudhry

was he on any therapy with anti-PD-1 medications. Looks like lichenoid dermatitis

The lichenoid infiltrate includes more plasma cells than might be expected for a "normal" lichenoid inflammatory pattern.  There is pigment in the dermis which I think might be tattoo rather than pigmentary incontinence of melanin. 

I think this may be an infective problem.  This includes the possibility of an atypical mycobacterium from infected tattoo material, and of course syphilis must be excluded, although the clinical details are not really suggestive of that.  Certainly the skin needs to be cultured for bacteria, atypical bacteria and fungi.

Lichenoid tattoo reaction. 

I also think that there is a exogenous pigment in some images.

So agree with Vincenzo: Lichenoid Tattoo reaction.

Dr Chaudhry:

Thank you for your comments. The final diagnosis is tattoo-associated, pseudolymphomatous lymphoid reaction pattern

Saulite I, Pekar-Lukacs A, Kerl K, Cozzio A, Hoetzenecker W, Guenova E. Pseudolymphomatous Reaction to Red Tattoo Pigment. Case Rep Dermatol. 2018;10(2):162-168. Published 2018 Jun 14