Growth-Curve Modeling of Nevi With a Peripheral Globular Pattern

Abstract

IMPORTANCEAlthough nevi with a peripheral rim of globules (peripheral globular nevi [PGN]) observed with dermoscopy are associated with enlarging melanocytic nevi, their actual growth dynamics remain unknown. Because change is a sensitive but nonspecific marker for melanoma, beginning to understand the growth patterns of nevi may improve the ability of physicians to differentiate normal from abnormal growth and reduce unnecessary biopsies.OBJECTIVE To study the growth dynamics and morphologic evolution of PGN on dermoscopy.

The study of nevi in children: Principles learned and implications for melanoma diagnosis

“…The growth rate of nevi with peripheral globules is comparable to the growth rate of some melanomas. 33,45 Unlike melanoma, nevi with peripheral globules grow symmetrically and do not develop any new structures or colors as they grow, lack melanoma-specific structures, and the peripheral globules become smaller and eventually disappear once nevus growth ceases. In patients >50 years, nevi with peripheral globules are rare, the incidence of melanoma among new or changing lesions is relatively high, and this dermoscopic pattern should prompt consideration of biopsy.…”

The BRAF and NRAS mutation prevalence in dermoscopic subtypes of acquired naevi reveals constitutive mitogen‐activated protein kinase pathway activation

“…Acquired naevi are a heterogeneous group that can be classified to have unique dermoscopic patterns that correspond to distinct microanatomical growth patterns . These distinct subsets of acquired naevi are also distinguished by their time of onset, life cycle and relative melanoma risks . Zalaudek et al .…”

“…These naevi are postulated to be an indicator for the de novo development of melanoma, corresponding to observed melanoma risk increasing almost linearly with naevus counts . On the other hand, the transient peripheral rim of globules (PG) dermoscopic pattern is recognized as the growth phase of naevi but does not indicate malignant transformation …”

Defining the Molecular Genetics of Dermoscopic Naevus Patterns

“…5c, d). Longitudinal dermoscopic studies found that PG naevi exhibit symmetrical enlargement over time, which implies that growth does not always indicate malignant transformation [37, 38]. Naevi with a peripheral rim of globules constitute 49% of enlarging naevi, with the relative risk of enlargement to be 28-fold higher (95% confidence interval) for naevi with a peripheral rim of globules than naevi without a peripheral rim of globules [36].…”

“…Naevi with a peripheral rim of globules constitute 49% of enlarging naevi, with the relative risk of enlargement to be 28-fold higher (95% confidence interval) for naevi with a peripheral rim of globules than naevi without a peripheral rim of globules [36]. Further, a study examining the growth pattern of PG naevi reported 96% ( n = 116) of lesions enlarged at some point during sequential monitoring, but these lesions display a decrease in number of the PG over time [38]. After a period of growth, PG naevi lose their rim of globules as the larger peripheral junctional nests extend horizontally to manifest either a reticular pattern (e.g., reticular naevus) or a mixed pattern with central globules/structureless area with a peripheral network [35].…”