Case Number : Case 1461 - 29 January Posted By: Guest

Apocrine adenocarcinoma. DD, metastasis from a breast primary.

Agree with apocrine carcinoma vs mets.

Thought about ceruminous gland adenocarcinoma too, but this should be in realtion to EAC and 'helical rim' probably not the right site for this.

I have asked dermpathpro team to replace these images with my originals which show a subtle but important difference.  Hopefully this will happen before the IHC is posted.

If metastatic, i would think to a Salivary Duct High Grade Carcinoma...but a primary cutaneous hydroadenocarcinoma is my first diagnosis. Angiolymphatic invasion is a typical findings.

I vote for metastatic carcinoma. If the patient is a man, from prostate, if a woman, from the breast.

And the new images???

Yeah makes me think of metastatic adenocarcinoma, I would consider lung primary too. I will wait to see the other images

Okay looks like my original images have not made it on.  Basically they showed nice interstitial (blue-tinged) mucin around the tumour islands (these images have had the contrast upped and unfortunately the subtle clue is not really appreciable).  Now you have the IHC too.... time to re-think.  I'm still hoping the original images will get posted.

I agree that primary cutaneous mucinous carcinoma is a great option. Still we cannot rule out a metástasis as there is no in situ component in this images and we dont know the clinical. Also particular is the fact that the mucin is not abundant so this case should correspond to the mixed variant with and extensive invasive ductal component. On the other hand, even if there is an adenoid variant of BCC and even one with true glandular differentiation I dont see other features typical of BCC in this images so I would discard this dx.

 I would love to see the complete lesion...

Odd that EMA is completely negative (for primary mucinous Ca). Given that the mucin was surrounding tumour islands and  BerEP4 is strongly positive,  BCC with pseudo glandular pattern is a possibility.

But difficult to explain LV invasion and the deep location of tumour!  Looking forward to the answer!

Well done Arti (again!) I only showed you the shave margin.  It was a solitary, indolent lesion (clinically BCC), from the ear that looked like a fairly typical all be it infiltrative and slighly metatypical basal cell carcinoma.  Confirmed by moderate BerEP4 with peripheral accentuation (no luminal staining) and completely negative EMA in the basaloid cells (most unusual for any type of adenocarcinoma and almost a specific pattern for BCC).  I was surprised to see this very isolated lymphovascular invasion when I was cutting innumerable levels to see if tumour was clear of the shave margin.  I have only seen lymphovascular invasion a couple of times with BCC (thousands of cases reported).  I suspect we may miss it or it is just very rare.  Given the slightly metatypical look I guess there is a moderate risk for metastasis and patient is having radiotherapy (instead of a re-exision) and will be followed up as for an SCC.  There was no glandular differentiation (just pseudoglandular). Try to remember an old adage that "uncommon variants of common lesions are still more common than rarities" (although not necessarily on Dermpathpro!).