ORIGINAL ARTICLE
Evaluation of large clinically atypical vulvar pigmentation
with RCM: atypical melanosis or early melanoma?
C. Theillac,
1
E. Cinotti,
2,3
J. Malvehy,
4
S. Ronger Savle,
1
B. Balme,
5
P. Robinson,
6
J.L. Perrot,
2,3
C. Douchet,
7
A.C. Biron Schneider,
2
L. Alos,
8
A. Garcia,
8
A. Barreiro,
4
B. Labeille,
2,3
G. Duru,
9
S. Dalle,
1
L. Thomas,
1
S. Debarbieux
1,3,
*
1
Dermatology Department, Centre Hospitalier de Lyon Sud, Hospices civils de Lyon, Universit e Claude Bernard Lyon 1, Pierre B enite,
France
2
Dermatology Department, University Hospital of Saint-Etienne, Saint-Etienne, France
3
Pour le Groupe Imagerie Cutan ee Non Invasive de la Soci et e Franc ßaise de Dermatologie, Paris, France
4
Dermatology Department, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
5
Pathology Department, Centre Hospitalier de Lyon Sud, Lyon, France
6
DRCI, Hospices Civils de Lyon, Lyon, France
7
Pathology Department, University Hospital of Saint-Etienne, Saint-Etienne, France
8
Pathology Department, Hospital Clinic of Barcelona, Barcelona, Spain
9
Department of Biostatistics, Universit e Claude Bernard Lyon 1, Villeurbanne, France
*Correspondence: S. Debarbieux. E-mail: sebastien.debarbieux@chu-lyon.fr
Abstract
Background Vulvar melanosis can occasionally be clinically challenging by mimicking an early melanoma.
Objective To report our experience of initial evaluation and follow-up in this peculiar subset of vulvar melanosis using
reflectance confocal microscopy (RCM).
Methods We retrospectively evaluated 18 consecutive cases referred for atypical vulvar pigmentation or for which mel-
anoma was considered and that underwent both RCM examination and histopathological assessment. In 13 cases with
available dermoscopic pictures, RCM classification was compared to dermoscopic diagnosis, and in all cases, the den-
sity of melanocytes was evaluated on biopsies using MelanA immunostaining.
Results Among the 18 atypical pigmented lesions, 17 vulvar melanosis and one melanoma were histologically deter-
mined. RCM concluded a benign vulvar melanosis in 10 of 17 cases, whereas dermoscopy did so in three of 12 cases.
RCM identified the only early malignant lentiginous melanoma. In several cases of vulvar melanosis, RCM could identify
foci of melanocytic hyperplasia in an otherwise benign pattern.
Conclusions In this clinically and dermoscopically challenging subset of vulvar pigmentations, RCM appears relevant
for initial extensive evaluation, especially to target initial biopsy sampling, and to perform non-invasive monitoring of foci
of melanocytic hyperplasia.
Received: 10 January 2018; Accepted: 22 May 2018
Conflicts of interest
None declared.
Funding source
This work is supported in part by grants from Lyon 1 University to LT, the Hospices Civils de Lyon (to LT) and The
Cancer Research Center of Lyon (to LT).
Introduction
Vulvar melanosis, also referred to as ‘vulvar lentiginosis’ and
‘vulvar melanotic macules’, is an extensive macular pigmenta-
tion affecting the vulval skin, with the histological changes in
basal hypermelanosis and a slight increase in the number of mel-
anocytes.
1
It can occasionally be clinically atypical (asymmetric,
large size, variegated pigmentation from light to dark brown and
irregular borders) and sufficiently so to simulate a malignant
lentiginous melanoma (MLM). In such cases, the differential
diagnosis between melanosis and melanoma is challenging. Der-
moscopy can be helpful, but in many cases, a biopsy is required
for histopathological examination.
2
To date, a few series of
© 2018 European Academy of Dermatology and Venereology JEADV 2019, 33, 84–92
DOI: 10.1111/jdv.15141 JEADV