Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan.
OBJECTIVE
To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma.


METHODS
Multicenter, retrospective study.


METHODS
University hospitals in Japan.


METHODS
Patients with melanocytic lesions on acral volar skin. A total of 712 melanocytic lesions (103 malignant melanomas, including 36 in situ lesions, and 609 melanocytic nevi) were consecutively collected from the files of 3 hospitals. Diagnoses of all the lesions had been determined histopathologically.


METHODS
Dermoscopic examination.


METHODS
The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the major dermoscopic patterns seen in benign and malignant melanocytic lesions on acral volar skin.


RESULTS
The parallel ridge pattern and irregular diffuse pigmentation showed extremely high specificity (99.0% and 96.6%, respectively) and very high negative predictive value (97.7% and 97.5%, respectively) in malignant melanoma. For melanoma in situ, the positive predictive value and diagnostic accuracy of the parallel ridge pattern were significantly higher than those of irregular diffuse pigmentation (P = .009 and P = .006, respectively). In melanocytic nevi, the specificity and positive predictive value of the parallel furrow pattern and/or the latticelike pattern were found to be very high (93.2% and 98.3%, respectively).


CONCLUSIONS
Dermoscopy is immensely helpful in differentiating malignant melanomas from melanocytic nevi on acral volar skin. Moreover, the parallel ridge pattern aids in detecting acral melanomas in early, curable stages.
Saida
Toshiaki
T
Department of Dermatology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan. tosaida@hsp.md.shinshu-u.ac.jp
Miyazaki
Atsushi
A
Oguchi
Shinji
S
Ishihara
Yasushi
Y
Yamazaki
Yoriko
Y
Murase
Sumio
S
Yoshikawa
Shusuke
S
Tsuchida
Tetsuya
T
Kawabata
Yasuhiro
Y
Tamaki
Kunihiko
K
D000328:Adult; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008499:Medical Records; D008545:Melanoma / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D008853:Microscopy / Q000379:methods*; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology