Thursday, January 24, 2008

Reed Nevus

Abstract: 11 yo boy with long history of black lesion left arm
History: The lesion has been present for years, little change but patient and parent are worried bout it.
O/E: 5 mm diameter papule with a peculiar serrated border

Clinical Photo(s)

Dermoscopic Image

Lab: N/A

Diagnosis or DDx: Reed Nevus (aka Pigmented spindle cell nevus)
Questions: For interest
Reason(s) Presented: When I first saw this patient, I thought it was a blue nevus. I sent the history and digital images to a few friends. Drs. Ian McColl and Stelios Minas thought it was a Reed nevus and recommended excision. Biopsy was done and confirmed their opinion.
References: The Reed Nevus is considered a variant of the Spitz nevus. It presents as a well-circumscribed deeply pigmented nodule on the extremities of young adults. Under the microscope, it resembles the Spitz nevus but is composed of spindled melanocytes with heavy melanin pigmentation. As in a Spitz nevus, this nevus is symmetrical with maturation and lack of deep dermal mitotic figures. Excision of suspected Reed nevi is recommended. For more information see: The Doctor's Doctor

Sunday, January 13, 2008

Pigmented lesion on left sole in a 66-year-old man

A 66-year-old man presented with a 6-month history of pigmented lesion on the left sole. It appeared to be increasing in size.

Examination of the skin showed a localized area of elongated pigmented hyperkeratotic plaque 1.0 x 0.5 cm on the sole of the right foot. The margin of the lesion was not well defined. It was non tender. Regional nodes were not enlarged.

A biopsy of the lesion was done.

Section shows skin composed of mainly epidermis with little underlying dermis. Marked hyperkeratosis is seen. Nests of atypical melanocytic cells are seen in the papillary dermis. The tumour cells are polygonal in shape, have vesicular nuclei with prominent nucleoli and eosinophilic cytoplasm. Some of the cells contain melanin pigment. Transepidermal migration of cells is also seen. Masson Fontana stain for melanin is positive. Features are suggestive of malignant melanoma. He was referred to plastic surgery for complete wide excision

Wednesday, December 26, 2007

Equestrian Cold Panniculitis (ECP)

We are resurrecting the DermPath blog which was started in 2005 by Dr. Ian McColl. It was a great idea, but it took the rest of us a few years to catch up with Ian. Hopefully, its time is NOW.

ECP is an uncommon disorder seen predominantly in female equestrians during the winter months. Recently, we presented a case on VGRD. We would like to present the dermatopathology here with some salient comments by H.R. Byers of Boston University's Dermatopathology Department. It appears that there's more to the story here than simple "panniculitis." Randy Byers kindly sent us the following photomicrographs. We believe this is the most complete collection of microscopic images of ECP on the web.

Dr. HR Byer's Comments:
Skin Pathology Laboratory, Boston University
The biopsies from the plaque and nodule show similar findings. These are:
• Parakeratosis, a flattened epidermis and basal cell layer vacuolization.
• Squamatization of the basal cell layer
• Necrotic keratiocytes
• Moderate to dense superficial and deep perivascular infiltrate

The differential diagnosis includes: chilblain lupus. It is interesting that a biopsy of dermis is sufficient for the diagnosis of ECP and does not require "panniculitis" given the clinical history. Nonetheless, in this case there is some inflammation identified in the fat around the eccrine glands.


4x Superficial

4x Deep

10 x Superficial

10 x Deep

20x Superficial

20x Deep

40x Superficial

40x Deep

Wednesday, July 20, 2005

This was a biopsy of a pink nodule on the shoulder.

The Answer

Sunday, April 03, 2005