Michael P. Lee, MD

03/29/2020

For anyone intubating C19 patients, a Atlanta local acrylic case company has made these protective shields free to hospitals.

Message me if interested.

04/15/2019

Sorry for the recent lack of posts. Be back at it soon.

04/10/2019

Spot dx unk #18. Ans choices in desc. Discussion tomorrow.

What is the diagnosis? A. Pityriasis rosea. B. Tinea corporis. C. Erythema multiforme. D. Rowell’s syndrome. E. Pityriasis lichenoides. F. Mycosis fungoides.

04/09/2019

Cutaneous lymphadenoma - currently believed to be variant of trichoblastoma - is a benign tumor most commonly on the head and neck of older individuals. They are typically biopsied to rule out BCC and other common malignancies.

These tumor are similar to other variants/derivatives of trichoblastoma, complete with CK20+ Merkel cells within tumor islands. Similar to trichoepitheliomas, the periphery of the tumor islands are positive for BCL2, differentiating it from BCC (diffuse staining of tumor).

The prior belief that these lesions were derived from pilosebaceous and sweat glands are fair assumptions since many of the tumor islands may show ductal like epithelium as well as sebocyte like cells.

Microscopically:
1. Dermal tumor composed of pale staining islands with dark blue rim, not dissimilar from clear cell BCC from low power.
2. Embedded in dense fibrous stroma.
3. Tumor cells show large nuclei with vesicular (translucent due to peripheral dispersion of chromatin) chromatin and prominent nucleoli. No mitotic figures.
4. Admixed with lymphocytes T>B
5. Basaloid rim of cells without clefting
6. Ductal like structures are negative for CEA but positive for EMA.

04/09/2019

New video on Cutaneous Lymphadenoma. Great job everyone for making the diagnosis. For those interested, there's a lymphoepithelial like carcinoma at end for comparison.

Cutaneous lymphadenoma - currently believed to be variant of trichoblastoma - is a benign tumor most commonly on the head and neck of older individuals. They...

04/09/2019

04/08/2019

Spot Dx Unknown 17. What is the diagnosis: Discussion tomorrow

A. Clear Cell Basal Cell Carcinoma B. Clear Cell Dermal Duct Tumor. C. Cutaneous Lymphadenoma. D. Mixed Tumor E. Trichilemmal Carcinoma

04/07/2019

Scary cells don’t always imply bad behavior.

This is an Atypical fibroxanthoma (AFX), a tumor that develops on the sun damaged skin of older people. While it is often rapidly growing, has bizarre multinucleated and pleomorphic cells with numerous mitotic figures, it is generally well circumscribed and removal of the lesion is typically curative (rare to recur or metastasize).

*Caveat* if tumor extends deeply into subcutis or invades other structures, consider undifferentiated pleomorphic sarcoma, which can be histopathologically and immunohistochemically indistinguishable (in fact, some consider AFX as a superficial variant of UPS).

04/04/2019

New vid on Sweet's disease. unknown 16.

If you eat too many SWEET CHERRY RED (color of the lesions) jolly ranchers, you may get a fever. This is Sweet's syndrome (aka acute febrile neutrophilic der...

04/04/2019

This is Sweet's syndrome (aka acute febrile neutrophilic dermatosis) - a somewhat uncommon lesion that typically presents after a URI. These lesions are red, hot, and quite tender. Patient's typically have an associated fever. The skin lesions are characteristically red and often lifted.

Sweets is an autoinflammatory neutrophilic dermatosis when one's own immune system damages tissue. There is also an association with other autoinflammatory conditions like rheumatoid arthritis, Lupus, as well as HLA B54.

Microscopically:
1. Neutrophils often diffusely through dermis
2. Massive subepidermal edema causing lifting of the skin
3. Fragmentation of the neutrophils (karyorrhexis)
4. Red cell extravasation
5. Occasional vasculitis (LCV)

04/02/2019

New vid on Trichofolliculoma up now on youtube

Momma and her babies! This is a trichofolliculoma, a benign follicular hamartoma most common on the head and neck. The presence of multiple hairs emptying th...