Case Number : Case 1652 - 25 October Posted By: Guest

A nice case from Dr Uma Sundram to test your skills.

Cheers, Geoff

I am thinking of panfolliculoma. We have areas resembling TE (image 2), areas with infundibular keratinization (image 4), image 3 I think represents isthmic differentiation (cells with abundant esinophilic cytoplasm and a focus of abrupt compact keratin). The last image shows ghost cells reminiscent of pilomatricoma. So I think this fits with panfolliculoma. 

Agree, pan-folliculoma.

Why not a Trichofolliculoma?...Trichofolliculomas also show pan follicular differentiation,  but the first image also shows a central cystically dilated infundibulum with radiating elements, typically seen with TF. This feature helps to differentiate from panfolliculoma as also the predominance of follicular germinative cells in PF. ( not seen here and which is why panfolliculoma usually mimic Trichoblastomas) 

Ofcourse, there is a cystic variant of panfolliculoma, which some consider as a variant of trichofolliculoma itself!

 I have similar case , looking for final diagnosis....

My impression was the same Arti had. I though of trichofolliculoma, it looks like an hamartomatous lesion centered on a dilated follicle surrounded and probably connected with smaller follicles. To diagnose a panfolliculloma I prefer to see well defined nodular tumors with solid lobules and more clear cut differentiation towards the different components of the hair follicle.

I see secondary and tertiary follicles radiating from a central one...and sincerely the last fig seems a keratin granuloma for me, or something like.

So agree with Trichofolliculoma

There are rather follicular germinative buds than vellus hair follicles radiating from the central crateriform structure lined by both infundibular and isthmic follicular epithelium. Agree with panfolliculoma.

Trichofolliculoma.

Trichfolliculoma 

Nice to see Robeldo back in this forum!!

What puzzeld me the clinical picture! Both TF or PF will be presented with a papule! Why this psoriasiform lesion with a pearly telangeictatic papule mimicking BCC! Parakeratosis inside the follicle with hypogranulosis. Looking again, could this be a case of Bowen (psoriasiform patch) that has been involved the pilosebacous follicle (the papule)? What about ki67?

Check this link.

https://www.ncbi.nlm.nih.gov/pubmed/17667180#

Great discussion as always. We went with trichofolliculoma for reasons discussed by arti. The patient has a background of actinic keratoses in that area which muddled the clinical picture.