Case Number : Case 1825 - 26 May - Dr Richard A Carr Posted By: Guest

Wrap up your week with this excellent Spot Diagnosis Case from Dr Richard A Carr - extra images to follow at 6pm.

Geoff Cross - DermpathPRO Projects

Microcystic adnexal carcinoma

Due to topography, histology and size I think we should consider digital papillary adenocarcinoma. I must recognize though that if I find this lesion in the scalp I would call it tubular adenoma

Syringoid eccrine carcinoma

Agree with Raul's diagnosis: Digital Papillary Adenocarcinoma 

there is invasive stromal desmoplasia.  

Digital pap adenocarc was my first impression (putting location in the context). 

Agree with Digital papillary adenocarcinoma.

Hoping clinical information of “nodule on hand” means “nodule on finger”, I favor digital papillary adenocarcinoma.

I would have also called this digital papillary adenocarcinoma.
(Does anyone still use Helwig's historic term "aggressive digital papillary adenoma" on certain occasions?)

I was delighted to see Richard's Ki67 highlighting the fact that a significant proportion of the p63+ cells are proliferating. 
In my opinion, this implies that digital papillary adenocarcinoma is more likely an adenomyoepithelioma / adenomyoepithelial carcinoma (or malignant adenomyoepithelioma, if you prefer) than... a breast carcinoma analogue. In the later scenario, the myoepithelial cells should have been negative.
Looking forward for your comments.

We had a great UK National EQA meeting yesterday in sunny East Birmingham. Wonderful talks on infectious pathology from Werner Kempf (Zurich). Well we have a bank holiday this Monday so I might not be able to clarify the exact location till Tuesday. I'll let this case run a bit for more opinions following the IHC.

I would go for a digital papillary adenocarcinoma. These tumours always come up with p63 ( useful in distinguishing from a hidradenoma, not a differential here). Ki67 can highlight upto 30% cells in the proliferation pool.

7 hours ago, Dimitris Chatzianastasiou said:

I would have also called this digital papillary adenocarcinoma.
(Does anyone still use Helwig's historic term "aggressive digital papillary adenoma" on certain occasions?)

I was delighted to see Richard's Ki67 highlighting the fact that a significant proportion of the p63+ cells are proliferating. 
In my opinion, this implies that digital papillary adenocarcinoma is more likely an adenomyoepithelioma / adenomyoepithelial carcinoma (or malignant adenomyoepithelioma, if you prefer) than... a breast carcinoma analogue. In the later scenario, the myoepithelial cells should have been negative.
Looking forward for your comments.

I do not like to use this term. This lesion has been shown to have malignant behaviour (recurrence, deep infiltration and possibility of distant spread, the latter quite infrequent but reported). Moreover, the overlap of morphological findings with the so called "adenomas" has been stressed in the past several times. 

Regarding the case, I think the immunos do not help too much. The lesion should be completely excised in order to have a complete picture of the neoplasm and performing an accurate diagnosis.

Thank you for your comment Raul; I totally see your point and I agree. I would have consciously avoided the term.
The immunostains, and particularly the percentage of Ki67 expressing p63+ cells, were interesting for me on a histogenetic, not a diagnostic or prognostic basis, given the discussion on an article from 2014: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131995/ 

Hi all,

First of all, it is my great pleasure to be here and always enjoy the shared cases presented here by friends and colleagues. What these photomicrographs show are not those of so-called aggressive digital papillary adenocarcinoma (ADPA) rather they represent for what being called as "eccrine papillary adenoma". The later lesion should not be mistaken for ADPA. The main difference between these two lesions is the pattern of myoepithelial cells. In so-called papillary eccrine adenoma (like this example), the myoepithelial cells surround individual tubules and ducts (highlighted by p63 in last photo).  In so-called ADPA, myoepithelial cells are intermingled with epithelial cells. Epithelial cells form ducts and tubules that are mixed with sheets of myoepithelial cells in between. As you probably know Sheng and I have a different opinion on so-called papillary eccrine adenoma. Please check our articles on this topic at https://www.ncbi.nlm.nih.gov/pubmed/24274672 and http://www.derm101.com/wp-content/uploads/dp0402a04.pdf 

3 hours ago, Masoud Asgari said:

Hi all,

First of all, it is my great pleasure to be here and always enjoy the shared cases presented here by friends and colleagues. What these photomicrographs show are not those of so-called aggressive digital papillary adenocarcinoma (ADPA) rather they represent for what being called as "eccrine papillary adenoma". The later lesion should not be mistaken for ADPA. The main difference between these two lesions is the pattern of myoepithelial cells. In so-called papillary eccrine adenoma (like this example), the myoepithelial cells surround individual tubules and ducts (highlighted by p63 in last photo).  In so-called ADPA, myoepithelial cells are intermingled with epithelial cells. Epithelial cells form ducts and tubules that are mixed with sheets of myoepithelial cells in between. As you probably know Sheng and I have a different opinion on so-called papillary eccrine adenoma. Please check our articles on this topic at https://www.ncbi.nlm.nih.gov/pubmed/24274672 and http://www.derm101.com/wp-content/uploads/dp0402a04.pdf 

 

Hello Masoud and thank you for sharing your expert opinion. I have read the articles you provided which are indeed really interesting. Personally, I think  the most important point is to be cautious when we find this kind of histology in acral sites (mainly fingers and toes) and always recommend complete excision (As I know that Richard did). Have you ever found any evidence of malignant transformation in the so called in-situ lesions? (either immunos like p53, cyclin d1 or by molecular biology) and a final question, have you ever tried other myoepithelial markers in the the tumors that did not express p63? (like we do in breast using smooth muscle actin and calponin). Thanks again  

Hi Raul, 

Yes, in our collection, we have few examples of papillary (eccrine or apocrine) adenocarcinoma in situ that also have an invasive component.These lesions should be considered as a true invasive papillary adenocarcinoma. The invasive component in our examples lies mostly in the deep part of the lesion; it composed of ducts and tubules that are smaller in size and irregular (geometric) in shape (compare with in situ component) and shows an infiltrative pattern. Staining with myoepithelial markers fail to demonstrate the presence of myoepithelial cells at the outermost part of ducts and tubules within an invasive component. The approach here is the same as one being used in breast ductal epithelial lesions. At least two myoepithelial markers such as p63, calponin, SMA or others should be used for evaluation of myoepithelial layer.

Treatment for papillary adenocarcinoma in situ is conservative but complete excision of the lesion to ensure the lesion is totally removed. 

fantastic case . Thanks for sharing the articles and the discussion. 

Looks like tubular apocrine carcinoma

Great discussion. My diagnosis: favouring a tubular papillary adenoma. I interpreted it as a relatively circumscribed lesion with even spacing of tubules some with micropapillary lining. I was re-assured by the pattern of p63 staining. However as Raul rightly pointed out I recommended complete excision given the difficulty of diagnosis on a part-biopsy. I suppose we could apply the same criteria for asking for complete excision as for other mitotically active benign lesions not least  in this case the difficulty of the differential diagnosis and possibility for malignant transformation.

From Kazakov's Adnexal book: Tubular apocrine adenoma (papillary eccrine adenoma) is a neoplasm in which micropapillary or rarely true papillary projections are seen but the tumour is well circumscribed, and composed of ductal structures with a distinct two cell layer. Solid areas and back-to-back glands are not present. In addition, the cystic ductal structure in DPA (digital papillary adenocarcinoma) are usually larger and more dilated than those in tubular adenoma.