Bullous malignant melanoma: an unusual differential diagnosis of a hemorrhagic friction blister.
BACKGROUND
A 66-year-old woman presented to our outpatient clinic with a 3 x 2.5-cm tense, hemorrhagic-appearing bulla on her forefoot. Histopathology and immunohistochemistry confirmed a transtumoral-transepidermal blister formation within an advanced acrolentiginous malignant melanoma (MM).


OBJECTIVE
To study bullous malignant melanoma.


METHODS
Blistering in MMs represents a rare but clinically important pitfall in clinical differential diagnosis. The blisters are typically due to the disruption of the cohesion between neoplastic cells and keratinocytes, but physical friction may also contribute.


RESULTS
Hemorrhagic blistering is, in many cases, a relatively insignificant finding in which frictional forces are imposed.


CONCLUSIONS
The case reported here underscores that in rare cases MMs, particularly if acrally located, can be complicated by hemorrhagic blistering. Because of the life-threatening consequences, one should be aware of this rare differential diagnosis.
Vogt
Thomas
T
Department of Dermatology, University Hospital of Regensburg, Regensburg, Germany. Thomas.Vogt@klinik.uni-renesburg.de
Brunnberg
Stephanie
S
Hohenleutner
Ulrich
U
Landthaler
Michael
M
D000368:Aged; D001768:Blister / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008545:Melanoma / Q000473:pathology* / Q000556:secondary; D012878:Skin Neoplasms / Q000473:pathology*