Melanosis Vulvar, lesion de aspecto aparatoso, pero de bajo riesgo.

Clinical and Dermoscopic Features of Vulvar Melanosis

JAMA Dermatology

TAKE-HOME MESSAGE

• In this observational cohort study in Italy spanning from 1998 to 2019, 129 women with vulvar melanosis were followed for a median of 13 years. Most women were premenopausal; the most common location for vulvar melanosis was the labia minora (43%); and 70% of lesions were smaller than 1 centimeter. Although nearly one-third of patients had slow evolution of the lesion, this ultimately stabilized, and no malignancy was noted in any of the patients' lesions during the follow-up period. In all 47 patients (36%) who underwent biopsy, vulvar melanosis was the final diagnosis. The most common dermoscopic pattern observed (75%) was homogenous or non-homogenous diffuse pigmentation in various shades of brown (100%) or black (60%), with only the rare presence of other colors and absence of other distinguishing features.

• Slow enlargement and change in brown–black pigment was not associated with malignant evolution of vulvar melanosis in this cohort.

– Caroline K. Crabtree, MD

Written by

Kelly H. Tyler MD, FACOG, FAAD

Benign vulvar melanosis can appear alarming on clinical exam because it is often darkly pigmented or even black, and many patients are unaware of its presence and cannot provide history regarding change or stability. The authors performed an excellent study outlining the key dermoscopic features of vulvar melanosis, especially with regard to features which differentiate it from vulvar melanoma.

The authors found that, if on dermoscopy a pigmented vulvar lesion is either a homogenous or non-homogenous black or brown color, lacks red, gray, or blue colors, and/or lacks typical dermoscopic parameters for melanocytic lesions (pigment network, dots and globules, pseudopods, and streaks), the clinician can diagnose vulvar melanosis with confidence and avoid biopsy. Most importantly, none of their patients with vulvar melanosis developed melanoma during the 20-year follow-up period, indicating that vulvar melanosis is indeed a benign entity with an extremely low risk of malignant transformation.

Although a small number of patients with vulvar melanosis in this study eventually developed an inflammatory vulvar dermatosis (such as lichen sclerosus), I personally see a large number of patients with either active or previously active inflammatory vulvar diseases who have vulvar melanosis; so, perhaps future studies are warranted to confirm this association.

Abstract

Importance

Vulvar melanosis is a common pigmentary change that accounts for most pigmented vulvar lesions. It presents as single or multiple asymptomatic macules or patches of varying size and color that may be asymmetric with poorly defined borders. The differential diagnosis of melanocytic lesions includes melanoma, which creates anxiety for patients and the physicians who diagnose the condition and treat the patients.

Objective

To evaluate the clinical and dermoscopic features of vulvar melanosis and their changes over time.

Design, Setting, and Participants

In this cohort study, patients with vulvar melanosis were recruited and followed up in the Department of Dermatology, University of Florence, Florence, Italy, between January 1, 1998, and June 30, 2019. Data on patient characteristics and on both the clinical and dermoscopic features of the vulvar lesions were collected. Each lesion was photographed clinically and dermoscopically at initial evaluation and at annual follow-up visits.

Main Outcomes and Measures

The clinical, dermoscopic, and histopathologic features of vulvar melanosis and their changes over time.

Results

This cohort study included 129 women (mean age at diagnosis, 46 years [range, 19-83 years]) with vulvar melanosis. A total of 87 patients (67%) with vulvar melanotic lesions were premenopausal, and 84 patients (65%) had received some type of hormone therapy. The most frequent location for vulvar melanosis was the labia minora (55 [43%]), followed by the labia majora (33 [26%]). In 39 of 129 cases (30%), the lesions increased in size and changed color after initial evaluation but ultimately stabilized. No malignant evolution was documented in any patient during a median follow-up of 13 years (range, 5-20 years).

Conclusions and Relevance

This study suggests that vulvar melanosis was a benign entity, and changes in lesions over time did not signify malignant transformation. An association between hormonal status and vulvar melanosis may be hypothesized.

JAMA Dermatology

Clinical and Dermoscopic Features of Vulvar Melanosis Over the Last 20 Years

JAMA Dermatol 2020 Aug 12;[EPub Ahead of Print], V De Giorgi, A Gori, L Salvati, F Scarfì, P Maida, L Trane, F Silvestri, F Portelli, F Venturi, P Covarelli, D Massi