Negative pigment network: an additional dermoscopic feature for the diagnosis of melanoma.
BACKGROUND
The negative pigment network (NPN) is seen as a negative of the pigmented network and it is purported to be a melanoma-specific structure.


OBJECTIVE
We sought to assess the frequency, sensitivity, specificity, and odds ratios (ORs) of NPN between melanoma cases and a group of control lesions.


METHODS
Digitalized images of skin lesions from 679 patients with histopathological diagnosis of dermatofibroma (115), melanocytic nevus (220), Spitz nevus (139), and melanoma (205) were retrospectively collected and blindly evaluated to assess the presence/absence of NPN.


RESULTS
The frequency of occurrence of NPN was higher in the melanoma group (34.6%) than in Spitz nevus (28.8%), melanocytic nevus (18.2%), and dermatofibroma (11.3%) groups. An OR of 1.8 emerged for the diagnosis of melanoma in the presence of NPN as compared with nonmelanoma diagnosis. Conversely, for melanocytic nevi and dermatofibromas the OR was very low (0.5 and 0.3, respectively). For Spitz nevi the OR of 1.1 was not statistically significant. When comparing melanoma with dermatofibroma, melanocytic nevus, and Spitz nevus, we observed a significantly higher frequency of multicomponent pattern (68.1%), asymmetric pigmentation (92.9%), irregularly distributed NPN (87.3%), and peripheral location of NPN (66.2%) in melanomas.


CONCLUSIONS
Further studies can provide the precise dermoscopic-histopathologic correlation of NPN in melanoma and other lesions.


CONCLUSIONS
The overall morphologic pattern of NPN, such as the irregular distribution and the peripheral location of NPN, along with the multicomponent pattern and the asymmetric pigmentation could be used as additional features in distinguishing melanoma from Spitz nevus and other benign lesions.
Centro di Riferimento Oncologico, National Cancer Institute, Aviano, Italy. Electronic address: pizzichetta@cro.it.
Maria A
MA
Pizzichetta
Centro di Riferimento Oncologico, National Cancer Institute, Aviano, Italy.
Renato
R
Talamini
Dermatology Section, Memorial Sloan Kettering Cancer Center, New York, New York.
Ash A
AA
Marghoob
Dermatology Research Center, University of Queensland, School of Medicine, Princess Alexandra Hospital, Brisbane, Australia.
H Peter
HP
Soyer
Dermatology and Skin Cancer Unit, Arcispedale Santa Maria Nuova, Istituto di Ricovero e Cura a Carattere Scientifico(IRCCS), Reggio Emilia, Italy.
Giuseppe
G
Argenziano
Istituto Dermopatico Immacolata, IRCCS, Rome, Italy.
Riccardo
R
Bono
Division of Dermatology, Pordenone Hospital, Pordenone, Italy.
M Teresa
MT
Corradin
Department of Dermatology, University of Florence, Florence, Italy.
Vincenzo
V
De Giorgi
Division of Dermatology, Merano Hospital, Merano, Italy.
Marian A
MA
Gonzalez
Department of Dermatology, University of Miami, Miami, Florida.
Isabel
I
Kolm
New York University School of Medicine, New York, New York.
Andrew W
AW
Kopf
Melanoma Unit, Department of Dermatology, Hospital Clinic, Institut d'Investigacions Biomediques August Pi i Sunyer, Barcelona, Spain.
Joseph
J
Malvehy
Department of Dermatology, University of Siena, Siena, Italy.
Niccolò
N
Nami
Department of Dermatology, University of Miami, Miami, Florida.
Margaret
M
Oliviero
Department of Dermatology, University of Modena and Reggio Emilia, Modena and Reggio Emilia, Italy.
Giovanni
G
Pellacani
Melanoma Unit, Department of Dermatology, Hospital Clinic, Institut d'Investigacions Biomediques August Pi i Sunyer, Barcelona, Spain.
Susana
S
Puig
Department of Dermatology, University of Miami, Miami, Florida.
Harold
H
Rabinovitz
Department of Dermatology, University of Siena, Siena, Italy.
Pietro
P
Rubegni
Department of Dermatology, University of Modena and Reggio Emilia, Modena and Reggio Emilia, Italy.
Stefania
S
Seidenari
Skin Cancer Unit, Istituto Tumori Romagna, Meldola, Italy.
Ignazio
I
Stanganelli
Centro di Riferimento Oncologico, National Cancer Institute, Aviano, Italy.
Andrea
A
Veronesi
Medical University of Graz, Graz, Austria.
Iris
I
Zalaudek
Division of Dermatology, Merano Hospital, Merano, Italy.
Pierfrancesco
P
Zampieri
Sydney Melanoma Diagnostic Center, Royal Prince Alfred Hospital and Discipline of Dermatology, University of Sydney, Sydney, Australia.
Scott W
SW
Menzies
D000328:Adult; D046169:Dermoscopy; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000473:pathology*