Association between Breslow thickness and dermoscopic findings in acral melanoma

Background: Dermoscopy is a useful tool for the diagnosis of acral melanomas (AMs). However, little is known about the influence of tumor thickness on the dermoscopic findings of AM. Objective: To investigate the affect Breslow thickness (BT) has on the dermoscopic patterns of AM. Methods: Data on cases of AM on the glabrous skin were collected from 4 university hospitals. We investigated the frequency of each dermoscopic feature of AM according to the BT. Statistical analysis was performed to investigate the association between the specific dermoscopic patterns and BT. Results: Multivariable analysis revealed that the colors red (odds ratio [OR] 16.482, 95% confidence interval [CI] 3.605-99.016); blue (OR 7.092; 95% CI 1.707-37.435); and white (OR 5.048, 95% CI 1.152-22.897) were more common in AM with BT >2 mm than those with BT ≤2 mm. Regarding patterns, atypical vascular (OR 34.589, 95% CI 6.458-305.852); blue-white veils (OR 9.605, 95% CI 1.971-72.062); and ulcers (OR 5.084, 95% CI 1.145-24.152) were more frequently detected in cases with BT >2 mm than those with BT ≤2 mm. Limitations: A retrospective study design and small sample size. Conclusion: This study showed an association between dermoscopic patterns and tumor thickness among patients with AM. Dermoscopy can be a useful adjuvant tool for predicting BT in AM.