Pigmented nodular melanoma: the predictive value of dermoscopic features using multivariate analysis.
BACKGROUND
Nodular melanoma (NM), representing 10-30% of all melanomas, plays a major role in global mortality related to melanoma. Nonetheless, the literature on dermoscopy of NM is scanty.


OBJECTIVE
To assess odds ratios (ORs) to quantify dermoscopic features of pigmented NM vs. pigmented superficial spreading melanoma (SSM), and pigmented nodular nonmelanocytic and benign melanocytic lesions.


METHODS
To assess the presence or absence of global patterns and dermoscopic criteria, digitized images of 457 pigmented skin lesions from patients with a histopathological diagnosis of NM (n = 75), SSM (n = 93), and nodular nonmelanocytic and benign melanocytic lesions (n = 289; namely, 39 basal cell carcinomas, 85 seborrhoeic keratoses, 81 blue naevi, and 84 compound/dermal naevi) were retrospectively collected and blindly evaluated by three observers.


RESULTS
Multivariate analysis showed that ulceration (OR 4.07), homogeneous disorganized pattern (OR 10.76), and homogeneous blue pigmented structureless areas (OR 2.37) were significantly independent prognostic factors for NM vs. SSM. Multivariate analysis of dermoscopic features of NM vs. nonmelanocytic and benign melanocytic lesions showed that the positive correlating features leading to a significantly increased risk of NM were asymmetric pigmentation (OR 6.70), blue-black pigmented areas (OR 7.15), homogeneous disorganized pattern (OR 9.62), a combination of polymorphous vessels and milky-red globules/areas (OR 23.65), and polymorphous vessels combined with homogeneous red areas (OR 33.88).


CONCLUSIONS
Dermoscopy may be helpful in improving the recognition of pigmented NM by revealing asymmetric pigmentation, blue-black pigmented areas, homogeneous disorganized pattern and abnormal vascular structures, including polymorphous vessels, milky-red globules/areas and homogeneous red areas.
Division of Medical Oncology - Preventive Oncology, Centro di Riferimento Oncologico, National Cancer Institute, Via Franco Gallini, 2, 33081, Aviano, Italy.
M A
MA
Pizzichetta
Department of Dermatology, University of Vienna, Vienna, Austria.
H
H
Kittler
Skin Cancer Unit, Istituto Tumori Romagna (IRST), Meldola, Italy.
I
I
Stanganelli
Istituto Dermopatico Immacolata, IRCCS, Rome, Italy.
R
R
Bono
Department of Dermatology, Fondazione Ospedale Maggiore Policlinico IRCCS, Milan, Italy.
S
S
Cavicchini
Department of Dermatology, University of Florence, Florence, Italy.
V
V
De Giorgi
Clinic of Dermatology, IRCCS San Martino - Ist, Genoa, Italy.
G
G
Ghigliotti
Dermatologic Clinic, Department of Medical Sciences, University of Turin, Turin, Italy.
P
P
Quaglino
Department of Dermatology, University of Siena, Siena, Italy.
P
P
Rubegni
Skin Cancer Unit, Arcispedale Santa Maria Nuova IRCCS, Reggio Emilia, Italy.
G
G
Argenziano
Unit of Epidemiology and Biostatistics, Centro di Riferimento Oncologico, National Cancer Institute, Via Franco Gallini, 2, 33081, Aviano, Italy.
R
R
Talamini
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002280:Basal Cell Carcinoma / Q000473:pathology; D002648:Child; D046169:Dermoscopy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D017492:Keratosis, Seborrheic / Q000473:pathology; D008297:Male; D008545:Melanoma / Q000473:pathology*; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000473:pathology; D015588:Observer Variation; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000473:pathology*; D055815:Young Adult