Dermatoscopic Pointillism

The patient is a 45 yo woman who presented with a new lesion on the right malar eminence.  It looked innocuous, perhaps, a lentigo.  The dermatoscopic image revealed a pointillist pattern.  One of our VGRD members, Dr. Phung Huynh described “pointillist nevus” some years ago.  While this is not a nevus, it shows a similar pattern.

A 3 mm punch biopsy was taken to establish what this lesion is and it is being presented for interest since I could find no reference to this phenomenon in PubMed.

For Art's Sake

Pathology: The biopsy shows a focal lichenoid lymphocytic infiltrate, scattered colloid bodies and melanophages consistent with lichen planus-like keratosis (LPLK).

 

Reference:

1. Pointillist nevi.

Huynh PM, Glusac EJ, Bolognia JL. J Am Acad Dermatol. 2001 Sep;45(3):397-400. PubMed.

2.  Dermoscopy of lichen planus-like keratosis: a model of inflammatory regression.  Bugatti L, Filosa G. J Eur Acad Dermatol Venereol. 2007 Nov;21(10):1392-7.  PubMed.

Nevi of Interest

In this post, we will present photos of interesting pigmented tumors.  Please feel free to send us interesting photos with brief captions.

7/25/2015
1) 15 y.o. girl with a 6 mm diameter congenital nevus on upper back.  Looks benign to me but has an interesting play of color.

2) 10 y.o. girl with a planaria shaped nevus on the right 4th toe.  Pigment globules likely represent growth.

3) 14 yo girl last seen 10 years ago.  Congenital nevus noted on l. upper back then, 9 mm diameter.  7.28.15 the lesion is 20 mm diameter. It has find terminal hairs.  There are two (?) satellite lesions near to it, the largest being 7 mm diameter.  The new lesion has a peculiar pattern dermatoscopically.  Still, I think it is benign.  I gave them a follow-up for 6 months.

Eccrine Hidrocystoma (Dermatoscopic Image)

The patient is a 21 year-old woman who has noticed a blue-purple papule on the bulb of the nose for two to three months.  If traumatized, it extrudes a clear fluid.

O/E:  There is a two mm in diameter bluish papule on the nose.  It was punctured with a # 11 blade and a drop of crystal clear fluid was extruded.

Dermatoscopic image shows a blue papule with a dark center and a paler periphery.

Diagnosis:  Probable Eccrine Hidrocystoma.

Plan:  This could be excised with a 2-mm punch biopsy.  It could also be observed.

Reference:

A Bluish Pigmented Cystic Lesion of the Nose.

Kluger N, et.al. Acta Derm Venereol. 2010 Sep;90(5):555-6.

Dermatoscopic Dilemmas

The dermatoscope is a source of endless wonder.  Here are two cases seen in the past week.

1. Congenital Nevus of Special Site

This 5 month old bi-racial (Black/Caucasian) foster infant was noted to have a slowly enlarging pigmented lesion in his left crural fold since around one month of age.

photo taken by Dr. Yoon Cohen

Question/Comment: Would anyone do anything other than follow this child?  Is the gray veil significant? The symmetrically distributed brown clods are to my mind markers for a benign growing nevus (cobblestone pattern).  There is no pertinent literature about growth in small congenital nevi.  Melanoma, in this age group and ethnicity, is exceedingly rare.

2. Unusual Subungual Hematoma

A 72 yo woman noted nail pigmentation that appeared shortly after knee replacement surgery.  I do not know if she had been anticoagulated after surgery, but the information would help.  The subungual color under the cuticle may be an example of a "pseudo-Hutchinson sign."

1 month follow-up

Note:  The one month follow-up shows distal progression of pigmented area confirming the clinical impression of subungual hematoma.

Question/Comment: The fact that this appeared shortly after surgery strongly suggests trauma rather than neoplasia.  If the patient was anticoagulated during surgery, that would be one more helpful historical fact.  The pattern of the long band could be called the "tadpole sign" -- I wonder if it is specific for subungual hematoma.

References:
1. Precursors to melanoma and their mimics: nevi of special sites.

Elder DE. Precursors to melanoma and their mimics: nevi of special sites. Mod Pathol. 2006 Feb;19 Suppl 2:S4-20.  Free Full Text.

2. Dermnet.nz.org has good sections on dermtoscopy: Introduction to Dermatoscopy   Dermatoscopic Features 

3. Overview of Nail Dermatoscopy