TOPLINE:

A meta-analysis of 41 studies found that parallel ridge and multicomponent patterns were the most significant dermoscopic features associated with acral lentiginous melanoma (ALM), whereas parallel furrow and latticelike patterns were most commonly linked to benign acral nevi.

METHODOLOGY:

• Researchers conducted a meta-analysis of 41 studies (27 cross-sectional, 9 diagnostic accuracy, and 5 cohort studies) comprising 8845 acral nevi and 801 ALMs.
• Of the included lesions, 2182 benign acral nevi were confirmed by histology and 702 were congenital melanocytic nevi; 45 melanomas were reported as amelanotic or hypomelanotic.
• Primary outcomes were the prevalence of dermoscopic features, including parallel ridge, parallel furrow, latticelike, multicomponent, and other pigmentation patterns.

TAKEAWAY:

• The parallel ridge pattern was the most sensitive (sensitivity, 79.6%) and specific (specificity, 99.4%) dermoscopic marker for ALM, occurring in 79.6% of melanomas vs 0.6% of nevi (P < .001). However, about 20% of ALMs lacked the ridge pattern, indicating that its absence should not be used to exclude cancer.
• The multicomponent pattern was more frequent in ALM than in nevi (45.8% vs 5.0%; P = .01), corresponding to 95.0% specificity and 45.0% sensitivity.
• Both parallel furrow (pooled prevalence, 51.8% vs 8.9%; P < .001) and latticelike patterns (pooled prevalence, 13.0% vs 2.7%; P < .001) were significantly more common in nevi than in ALM, and both patterns showed high specificity for benign acral lesions (91.1% and 97.3%, respectively).
• Researchers found no differences in the fibrillar, homogeneous, globular, reticular, and nontypical patterns between nevi and ALMs.

IN PRACTICE:

“This systematic review and meta-analysis confirms that a hierarchy of dermoscopic features exists in the diagnosis of ALM,” the authors wrote. Although rare, ALM “often carries a worse prognosis, partially due to delayed recognition and the heterogeneity of its clinical presentation. By clarifying which dermoscopic patterns most reliably distinguish ALM from benign acral lesions, this study provides evidence-based criteria to support earlier recognition, facilitate timely treatment, and improve clinical outcomes,” they added. 

SOURCE:

The study was led by Chidimma J. Okwara, MD, Department of Dermatology, Baylor College of Medicine, Houston, and was published online on March 11 in JAMA Dermatology.

LIMITATIONS:

The analysis was limited by heterogeneity across studies, retrospective single-center design, and small cohorts. Additionally, skin phototype was underreported.

DISCLOSURES:

This research received partial support from a National Institutes of Health/National Cancer Institute support grant and utilized the Biostatistics Resource Group. The authors reported having no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.