Melanoma risk greater in melanocytic lesions with peripheral globules on lower limbs

Melanocytic lesions in the lower extremities that are marked by peripheral globules should be closely watched for melanoma development, according to a study.

“Morphology and biology of nevi with peripheral globules are well known, while that of melanomas with peripheral globules remain unclear,” Ana F.A. Moraes, MD, of the department of cutaneous oncology at A.C. Camargo Cancer Center in São Paulo, Brazil, and colleagues wrote.

The researchers retrospectively analyzed 401 melanocytic lesions with peripheral globules to compare dermoscopic characteristics of nevi and melanomas with peripheral globules.

By investigating the dermoscopic patterns and structures of the lesions, the researchers hoped to identify features that were most likely to differentiate melanoma from nevi.

Results showed that among 179 lesions that were excised, 10.22% were melanoma, while 34.42% were melanocytic nevi. The most common site of melanoma lesions was in the lower extremities (P < .01), while nevi were most commonly found on the trunk.

Melanomas were more likely to have a disorganized pattern, while nevi were more organized. Disorganized lesions were more likely to be excised (OR = 4; P < .01).

In addition, melanomas were marked by blotches, atypical dots and globules, or atypical vessels (P < .01), according to the study.

More than 60% of the melanoma lesions were found in individuals aged 30 to 50 years.

Inclusion bias resulting from the retrospective study design may limit the applicability of the findings.

“We concluded that melanocytic lesions with [peripheral globules] must be carefully assessed in middle-aged individuals from 30 to 50 years of age, with special attention to those located on the lower limbs,” the researchers concluded. “When found, [peripheral globules] should not be labeled as a malignant structure, and other features from the patient and the lesion may be considered.”