Extramammary Paget Disease (EMPD)

Had a case today about EMPD which actually was an old case from last year. It made me open my notes, and voila! Another bunch of pearls of wisdom.

1. EMPD has similar features as glandular cells eg vacuolated.

2. Differential diagnosis of EMPD to keep in mind:

i. Porocarcinoma

ii. Bowen disease

3. However, Bowen disease is CK5/6 positive, and EMPD is negative.

4. Another useful immunohistochemistry is p63. P63 is supposed to be positive for primary EMPD and negative for secondary EMPD.

Point number 4 caused me a headache because it was negative although clinically and histologically it does look like primary EMPD. But like a certain teacher once said, trust your immunohistochemistry like you trust your spouse. You can love them 100%, but you cannot trust them 100%.

Holy moly!

Comments

8 L's and DRUGS

I am so happy that I found an educational gem by Sullivan Nicolaides Pathology , a private pathology lab in Australia. There are some videos of live lectures that one can find here. I am particularly excited (and maybe starstruck) to find Professor David Weedon's lectures here -- as I am particularly fond for Dermatopathology. A particular thing I learned today from Professor David Weedon was a checklist mnemonic for perivascular infiltrate in the skin: 8L's and DRUGS Light reaction Lymphoma (and pseudo) Leprosy Lues Lichen striatus Lupus erythematosus Lipoidica (and incomplete granuloma annulare) Lepidoptera (arthropods etc) Dermatophyte Reticular erthymatous mucinosis Urticaria Gyrate erythema Scleroderma

How to gross a Whipple's specimen

Just mentioning presence of a Whipple's specimen in the lab would bring throngs of histopathology trainees to observe the grossing of the specimen. It is associated with intimidating combination of organs, many margins to remember, and last but definitely not least, the lament of a trainee saying: "Where is the tumour??" When I was a second year Pathology Masters student (first year Histopathology trainee), a senior trainee taught us a simplified way to gross a Whipple's specimen. It is the same as any other textbook, but the lack of wordiness (as compared to the textbook) make it less intimidating. (Picture from www.pancreapedia.org) 1. Margins Stomach (proximal margin) Duodenum (distal margin) Uncinate (Soft tissue margin) Anterior pancreas Common...

Dermatopathology Pearls

Some pointers taken from the Dermatopathology RCPA Quality Assurance Programme: 1. Glomus tumour : It can occur in other places other than the nailbed. Other variants may be glomangioma, glomangiomyoma and symplastic glomus tumour. Malignant glomus tumour is a rare entity. A differential is spiradenoma. 2, Fixed drug eruption : Composed of a combination of erythema multiforme -like changes, mixed inflammatory infiltrate, and melanophages in the superficial dermis. Here is a nice explanation on the clinical features . 3. Chondrodermatitis nodularis helicis Painful nodule typically in the upper part of ear in older males. 4. Naevus cell rests in lymph nodes. Apparently it is not that uncommon (22% of lymphadenectomies in a large study). 5. Superficial acral fibromyxoma Circumscribed but non encapsulated lesions, typically at fingers and toes. Strongly CD34 positive. Differentials include: 1. Low grade fibromyxoid sarcoma: Deep soft tissue lesion, ...

The Histopathologoid

Search This Blog