A case posted to the IDS forum by Landi Christian
Age: 55 years, Sex: female, Location: nail finger 1, right
Clinical history: This black stripe developed in 2 years after a "fungal infection"...
Diagnosis: Complete excision performed today
Question: Could it be anything different?
Answers (comments):
Giuseppe Argenziano (11/13/2010 8:55:42 AM):
hmmm very suspicious...
Landi Christian (11/13/2010 9:31:59 AM):
At a second glance I realized that this is a sort of pseudo Hutchinson's sign due to the transparency and thickness of the lateral fold's stratum corneum. BTW great and appealing new architecture of this site!
Muir James (11/13/2010 10:20:01 PM):
Irregular shape, width and pigmentation. Should be bad at this age.
Fox Gary (11/13/2010 11:55:48 PM):
I wonder if those shark fins are somehow analogous to streaks elsewhere. Is there anything micro-anatomically that could give rise to those?
Christain, could you elaborate on your excision? Did your excision include the lateral nail matrix? Were you able to see a well defined lesion clinically?
Pyne John (11/14/2010 4:10:56 AM):
Bad guy until proven otherwise.
Sundaramoorthy Srinivasan (11/14/2010 4:22:53 AM):
This looks as if a sub unugual melanoma starting from the medial edge of the nail matrix. If that is not the case it could be just a collection of fungal spores like in Tinea nigra.
Landi Christian (11/14/2010 11:29:36 AM):
It was clinically defined, Gary. This was the excision.
Zalaudek Iris (11/15/2010 8:19:47 AM):
I do not think about melanoma here because of the sharp lateral demarcation. I am curious whether there is overlying hemorrhage on an infection..
Burns John (11/16/2010 3:01:51 PM):
Agree with IZ that with the "shark-tooth-like" pattern this would make me wonder about subungal hemorrhage; comparable to an the air fluid level phenomenon. The time frame for hemorrhage is not quite right, unless repetitive trauma or as IZ mentioned a concomitant infection + recent trauma. I guess you could clip the nail and ensure there is melanin in the plate. If so then a bx is warranted, if not then confirm hemorrhage with a clip and guiac + culture. However, since the bx is done I will wait on the path. Thanks for the case.
Histo for the case
Diagnosis: A couple of pathologist were involved: in situ melanoma. We will soon perform full-thickness skin grafting after total nail unit, as suggested by:
Duarte AF, Correia O, Barros AM, Azevedo R, Haneke E. Nail matrix melanoma in situ: conservative surgical management. Dermatology. 2010;220(2):173-5
Nail matrix melanoma
Nail matrix melanoma is a type of acral melanoma. Early lesions may show widening pigmented bands, irregular in spacing and varying in colour (including pink or red in amelanotic melanoma). A positive Hutchinson's sign refers to pigment arising on the skin adjacent to the nail, which is rare in benign naevi. Micro–Hutchinson sign was defined by the visibility on dermoscopy of a pigmentation of the periungual tissues that could not be seen with the naked eye. Changes may be observed by dermoscopy before they are evident clinically. Single pigmented bands should be followed by dermoscopy after several months.