Case Number : Case 2167 - 28 September 2018 Posted By: Dr. Richard Carr

This is the classical case impossible to hit for me. Anyway my first spot is Mycosis Fungoides, hypopigmnted variant. 

I agree with hypopigmented micosis fungoides

Spongiotic changes in epidermis with lymphocytic infiltrate around sweat glands

Could it be lichen striatus [ i do not want to commit on MF ]

I won't jump to the diagnosis of MF straightway considering the age and clinical picture. The clinical picture suggests lichen striatus. Histology supports it with parakeratosis,  mild acanthosis, spongiosis and a dermal lymphocytic infiltrate around vessels and eccrine glands. The lymphocytes in the epidermis do not look abnormal to call it MF. Not surprisingly,  lichen striatus has been called a chameleon! 

Is the patient Indian?

lichen striatus

The lymphocyte exocytosis is not prominent enough for me to consider MF. Although the lichenoid lymphocytic infiltrate is rather mild, given the peri-eccrine involvement (I think Richard is giving us a hint here), I favor lichen striatus. However if this is a long standing process (longer than 1-2 years) I would also consider ILVEN.

Well done!!! I omitted the clinical suggestion of lichen striatus hoping to get the pitfall diagnosis. Naughty me!

I agree with lichen striatus being the favoured clinicopathological diagnosis with the syringotropic clue (but that is also a clue to MF of course).

I'd say you're a true skilled dermatopatologist for thinking of this diagnosis we don't see too often.

I'm sure patient is South Asian if not Indian.

I'd like to thank the kind dermatology colleague for the clinical image not to mention in handing me the correct diagnosis as blind I was considering MF.