10.5826/dpc.1204a194
Introduction: Differentiating early melanoma from other flat pigmented lesions on the head and neck is challenging both clinically and dermoscopically, partly due to the wide differential diagnosis and the lack of specific diagnostic algorithms.
Objectives: To review publications covering the dermoscopic features of pigmented macules on the head and neck.
Methods: Embase and PubMed (Medline) database from Jan 2015 to Jan 2021 were searched using a four-step search. Keywords used were dermoscopy/dermatoscopy or epiluminescence microscopy, lentigo maligna (LM), lentigo maligna melanoma (LMM), lichen-planus-like-keratosis (LPLK), solar lentigo (SL), seborrhoeic keratosis (SK), pigmented actinic keratosis (PAK), pigmented Bowen’s disease (pBD), pigmented intraepidermal carcinoma (pIEC) and head and neck.
Results: The commonest reported dermoscopic features of facial melanoma were irregular dots, atypical dots/globules, asymmetric pigmented follicular openings (APFO), rhomboid grey/ black structures, increased vascular network, brown globules/dots and a pattern of circles. Pseudopods, radial streaming, blue white veil, irregular blotches, scar-like depigmentation and atypical pigment network  were recorded in low frequencies. For PAK, pBD and pIEC perifollicular erythema, white/yellow surface scale, linear wavy vessels around hair follicles, hair follicular openings surrounded by a white halo, evident follicles or follicular or keratotic plugs, rosette sign and sharply demarcated borders were the salient features.
Conclusions: Further studies are needed to determine the dermoscopic criteria for pigmented melanocytic and non-melanocytic lesions on the head and neck. Furthermore, there is a gap in the knowledge of site-specific dermoscopic features on specific sites, namely ears, nose, cheeks, scalp and neck which will also benefit from further studies.
text/xml
2160-9381
2268
en
Tony Dicker
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
head and neck
Pigmented macules on the head and neck: A Systematic Review of dermoscopy features
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Review
2022-10-31
2021-12-21
2022-10-31
2022-12-02
e2022194
Dermatol Pract Concept
Introduction: Differentiating early melanoma from other flat pigmented lesions on the head and neck is challenging both clinically and dermoscopically, partly due to the wide differential diagnosis and the lack of specific diagnostic algorithms.
Objectives: To review publications covering the dermoscopic features of pigmented macules on the head and neck.
Methods: Embase and PubMed (Medline) database from Jan 2015 to Jan 2021 were searched using a four-step search. Keywords used were dermoscopy/dermatoscopy or epiluminescence microscopy, lentigo maligna (LM), lentigo maligna melanoma (LMM), lichen-planus-like-keratosis (LPLK), solar lentigo (SL), seborrhoeic keratosis (SK), pigmented actinic keratosis (PAK), pigmented Bowen’s disease (pBD), pigmented intraepidermal carcinoma (pIEC) and head and neck.
Results: The commonest reported dermoscopic features of facial melanoma were irregular dots, atypical dots/globules, asymmetric pigmented follicular openings (APFO), rhomboid grey/ black structures, increased vascular network, brown globules/dots and a pattern of circles. Pseudopods, radial streaming, blue white veil, irregular blotches, scar-like depigmentation and atypical pigment network  were recorded in low frequencies. For PAK, pBD and pIEC perifollicular erythema, white/yellow surface scale, linear wavy vessels around hair follicles, hair follicular openings surrounded by a white halo, evident follicles or follicular or keratotic plugs, rosette sign and sharply demarcated borders were the salient features.
Conclusions: Further studies are needed to determine the dermoscopic criteria for pigmented melanocytic and non-melanocytic lesions on the head and neck. Furthermore, there is a gap in the knowledge of site-specific dermoscopic features on specific sites, namely ears, nose, cheeks, scalp and neck which will also benefit from further studies.
Tony Dicker
2022/10/31
10.5826/dpc.1204a194
e2022194
Faculty of Medicine at the University of Queensland
2160-9381
head and neck
en
e2022194
Li W, Zhang C. 180 The investigation of dermoscopy in differential diagnosis of facial actinic keratosis. Journal of Investigative Dermatology. 2017;137(5):S31.
Pigmented macules on the head and neck: A Systematic Review of dermoscopy features
https://dpcj.org/index.php/dpc/article/download/2268/1814
         Pigmented Macules on the Head and Neck:
        A Systematic Review of Dermoscopy Features
                                      Gracy Gouda1,2, John Pyne1, Tony Dicker2


1 Faculty of Health Sciences, University of New South Wales, Sydney, Australia
2 Faculty of Medicine, University of Queensland, Australia



Key words: dermoscopy, lentigo maligna melanoma, solar lentigo, pigmented actinic keratosis, head and neck
Citation: Gouda G, Pyne J, Dicker T. Pigmented macules on the head and neck: A Systematic Review of dermoscopy features.
Dermatol Pract Concept. 2022;12(4):e2022194. DOI: https://doi.org/10.5826/dpc.1204a194
Accepted: March 17, 2022; Published: October 2022
Copyright: ©2022 Gouda et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use,
distribution, and reproduction in any medium, provided the original authors and source are credited.
Funding: None.
Competing interests: None.
Authorship: All authors have contributed significantly to this publication.
Corresponding author: Gracy Gouda, University of New South Wales (UNSW), University of Queensland (UQ), Trinity Medical Centre,
Wagga Wagga, 54 Best Street, Wagga Wagga, NSW 2650, E-mail address: gracy.gouda@uqconnect.edu.au




  ABSTRACT             Introduction: Differentiating early melanoma from other flat pigmented lesions on the head and neck
                       is challenging both clinically and dermoscopically, partly due to the wide differential diagnosis and the
                       lack of specific diagnostic algorithms.
                       Objectives: To review publications covering the dermoscopic features of pigmented macules on the
                       head and neck.
                       Methods: Embase and PubMed (Medline) database from January 2015 to January 2021 were
                       searched using a four-step search. Keywords used were dermoscopy/dermatoscopy or epiluminescence
                       microscopy, lentigo maligna, lentigo maligna melanoma , lichen-planus-like-keratosis, solar lentigo,
                       seborrheic keratosis, pigmented actinic keratosis (PAK), pigmented Bowen disease (pBD), pigmented
                       intraepidermal carcinoma (pIEC) and head and neck.
                       Results: The commonest reported dermoscopic features of facial melanoma were irregular dots, atypi-
                       cal dots/globules, asymmetric pigmented follicular openings, rhomboid gray/ black structures, increased
                       vascular network, brown globules/dots and a pattern of circles. Pseudopods, radial streaming, blue
                       white veil, irregular blotches, scar-like depigmentation and atypical pigment network were recorded
                       in low frequencies. For PAK, pBD and pIEC perifollicular erythema, white/yellow surface scale, linear
                       wavy vessels around hair follicles, hair follicular openings surrounded by a white halo, evident follicles
                       or follicular or keratotic plugs, rosette sign and sharply demarcated borders were the salient features.
                       Conclusions: Further studies are needed to determine the dermoscopic criteria for pigmented melano-
                       cytic and non-melanocytic lesions on the head and neck. Furthermore, there is a gap in the knowledge
                       of site-specific dermoscopic features on specific sites, namely ears, nose, cheeks, scalp and neck which
                       will also benefit from further studies.




Review | Dermatol Pract Concept. 2022;12(4):e2022194                                                                                1
Introduction                                                             (Figure 1) features with non-melanoma skin lesions includ-
                                                                         ing solar lentigo (SL) (Figure 2), seborrhoeic keratosis (SK)
Melanoma diagnosis on chronic sun-damaged skin is                        (­Figure 3), pigmented actinic keratosis (PAK)/ pigmented
challenging to clinicians both clinically and dermoscopi-                Bowen disease (pBD)/ pigmented intraepidermal carcinoma
cally [1-5]. This is partly due to the overlap of melanoma               (pIEC) (Figures 4 and 6) and lichen planus like keratosis




Figure 1. (A) Macroscopy of a pigmented lesion on the scalp (vertex) of a 49-year-old male. (B) Dermoscopy features of the lesion showing
brown and gray structureless areas (oval shape), gray structureless areas (hollow arrows), white regression areas (solid black arrow) and
brown dots/globules (orange solid arrow)-Fotofinder dermoscopy, Medicam 1000, magnification x20. Diagnosis: melanoma in situ (lentigo
maligna). (C)Macroscopy of a pigmented lesion on the left cheek of a 69-year-old male with a long standing “freckle” on his left cheek.
(D) Dermoscopy features of the lesion showing a pattern of circles with multiple asymmetrically pigmented hair follicles (round shape),
circle in circle (solid arrow), target shapes (hollow arrows), erythema/ structureless pink areas (black oval shape) and gray areas (blue oval
shape)-Fotofinder dermoscopy, Medicam 1000, magnification x20. Diagnosis: melanoma in situ (lentigo maligna). (E) Macroscopy of a
pigmented lesion on the right cheek of a 70-year-old male. (F) Dermoscopy features of the lesion showing a pattern of gray-brown granules/
peppering (round shapes), asymmetrically pigmented follicular opening (arrow) and brown-black areas (oval shape)-Fotofinder dermoscopy,
Medicam 1000, magnification x20. Diagnosis: melanoma in situ (lentigo maligna).



2                                                                                    Review | Dermatol Pract Concept. 2022;12(4):e2022194
                    Figure 2. Left side – Macroscopy: a 75-year-old male (BH) with a pigmented lesion on the left
                    side of the nose. Right side - Dermoscopy - showing gray areas (arrows), white circles (square)
                    and brown interfollicular pigmentation (oval shape). Diagnosis: pigmented actinic keratosis and
                    solar lentigo, combined. Fotofinder dermoscopy, Medicam 1000, magnification x20.




                      Figure 3. Left side – Macroscopy - A 71-year-old male with a pigmented lesion on the left
                      side of the forehead. Right side – Dermoscopy - pink and gray areas (oval shapes), ill-defined
                      margins, increased vascularity with curved vessels (square). Diagnosis: seborrheic keratosis.
                      Fotofinder dermoscopy, Medicam 1000, magnification x20.


(LPLK) (Figure 5) [5,6]. Compared to other parts of the                cryosurgery, curettage/electrodessication as well as topical
body, the head and neck region has features of sun-damage,             treatment may result in scarring and hypopigmentation add-
increased elastosis, increased intensity of hair follicular open-      ing to the diagnostic difficulty.
ings and skin appendages as well as flat rete ridges creating              Approximately 20% of melanomas occur on the head
a pseudo-pigment network. These collectively can render the            and neck [7]. The estimated five year survival rate on the
extra-facial diagnostic algorithms for melanoma diagnosis              head and neck is lower (74%) compared to melanoma lo-
unreliable. Furthermore, prior therapeutic interventions like          cated on the extremities (84%) and trunk (82%) [8,9].



Review | Dermatol Pract Concept. 2022;12(4):e2022194                                                                             3
    Figure 4. (A) Macroscopy- A 50 -year -old female with a lesion on the left check. (B) Dermoscopy- Diagnosis: pigmented
    actinic keratosis.(C) Macroscopy- A 67-year-old male with a pigmented lesion on the right eyebrow. (D) Dermoscopy
    - ­Diagnosis: pigmented Bowen disease. (E) Macroscopy-A 33 -year -old female with a left cheek lesion. (F)Dermoscopy
    -­Diagnosis: pigmented intraepidermal carcinoma.Fotofinder dermoscopy, Medicam 1000, magnification x20




                Figure 5. Macroscopy - Left side - A 71-year-old male with a pigmented lesion on the left side of
                the forehead with peppering or annular granular structures composed of scattered dots of gray
                pigmentation all over the lesion. Dermoscopy - Right side - Diagnosis: lichen planus like kerato-
                sis. Fotofinder dermoscopy, Medicam 1000, magnification x20.



4                                                                              Review | Dermatol Pract Concept. 2022;12(4):e2022194
Lentigo maligna (LM), formerly known as Hutchinson                  In the second step studies covering melanoma, LM, LMM,
melanotic freckle (HMF) is the commonest type of in situ            LPLK, solar lentigo (SL), SK, pigmented actinic keratosis
melanoma on sun-exposed areas [10]. It tends to develop             (PAK), pBD, basal cell carcinoma (BCC) and squamous cell
clinically as a brown macule on chronic sun-exposed sites.          carcinoma (SCC) were identified. Studies conducted on the
Dermoscopically the differential diagnosis is variable and          head and neck were included in the third search step. The
the clinical and dermoscopic margins tend to be ill-defined         last step was combining the above three steps.
which can lead to incomplete excisions [11]. Progression to            This review was structured according to the Preferred
an invasive stage is called lentigo maligna melanoma (LMM)          Reporting Items for Systematic Reviews and Metanalyses
which represents 4%-15% of all invasive melanomas [12].             (PRISMA) guidelines. To identify all relevant studies the ref-
Estimations of lifetime risk of LM progressing into LMM is          erence section of the studies was searched for studies not
5%-20% [11].                                                        identified by the search. Where possible, some authors were
   Dermoscopy is a non-invasive technique that increases            contacted. Studies on raised lesions and those studies based
the diagnostic accuracy of skin lesions. In expert hands di-        exclusively on reflectance confocal microscopy (RCM) were
agnostic accuracy for melanoma can be increased by up to            excluded. Other exclusion criteria were studies based on sur-
49% [13,14]. Histology is considered to be the gold standard        gical or medical treatments as well as studies based on con-
for diagnosis. Additional stains including melan-A/MART-1           junctiva and other mucosal surfaces. Finally, abstract only
stain was found to aid in the detection of invasive disease in      and non- English studies were also excluded.
29% of melanoma cases [15]. Histologically LM is character-            PubMed and Embase search were conducted as de-
ized by atypical melanocytes proliferating along the dermo-­        tailed below:
epidermal junction as single cells or nests. Pagetoid spread           PubMed (Medline)
may be minimal or absent. In contrast, LMM displays atyp-              Dermoscopy
ical melanocytes in single cells and nests within the dermis           “dermoscopy”[MeSH Terms] OR dermoscopy[tiab] OR
[16]. The diagnosis of LM and LMM can be challenging due            dermatoscopy[tiab]
to the extent of ultraviolet damage and/or prior therapeutic           Pigmented lesions
intervention like cryosurgery or topical treatments [11]. The          “Nevus, Pigmented”[Mesh] OR pigmented lesion* OR
dermoscopic features also vary with the site of the melanoma,       melanoma[tiab] OR “lentigo maligna” OR “lichen planus
histological type and depth of invasion (­Table 1) [9].             like keratos*” OR “solar lentigo” OR “seborrheic keratos*”
                                                                    OR “Keratosis, Seborrheic”[Mesh] OR “Melanoma”[Mesh]

Objectives                                                          OR “pigmented bowen’s disease” OR “pigmented actinic
                                                                    keratos*” OR “basal cell carcinoma*” OR “squamous
To review publications covering the dermoscopic features of         cell carcinoma*” OR “Carcinoma, Basal Cell”[Mesh] OR
pigmented macules on the head and neck.                             “­Carcinoma, Squamous Cell”[Mesh]
                                                                       Head/neck
                                                                       “Head”[Mesh] OR “Neck”[Mesh] OR Head[tiab] OR
Methods                                                             neck[tiab] OR face[tiab] OR scalp[tiab]
Embase and PubMed (Medline) database from January 2015                 Embase
to January 2021 were searched. A 4-step systematic review              Dermoscopy
was conducted. The first step used keywords including der-             ‘epiluminescence microscopy’/exp OR dermoscopy:ti,ab
moscopy/dermatoscopy or epiluminescence microscopy.                 OR dermatoscopy:ti,ab



              Table 1. Cengiz et al 2015. Dermoscopic Features according to the histological
                               subtype of melanoma on the head and neck.
        Dermoscopic Features                              LMM                          LMM- in situ                  P value
 Asymmetry                                        24 (60%) (κ = 1)                  12 (60%) (κ = 0.65)            P = 0.0001
 Pseudo-network                                 24 (60%) (κ = 0.80)                 8 (40%) (κ = 0.70)             P = 0.0005
 Irregular dots                                 32 (80%) (κ = 0.83)                  15 (75%) (κ = 1)              P = 0.121
 Scar-like depigmentation                       12 (30%) (κ = 0.86)                 6 (30%) (κ = 0.69)             P = 0.032
 2 different colors                               32 (80%) (κ =1)                   15 (75%) (κ = 0.83)            P = 0.005
 3 different colors                                8 (20%) (κ =1)                   5 (25%) (κ = 0.80)             P = 0.005
 4 different colors                                        –                                 -                     P = 0.0005



Review | Dermatol Pract Concept. 2022;12(4):e2022194                                                                            5
    Pigmented lesions                                          Clinical and Dermoscopic Features of
    ‘pigmented nevus’/exp OR pigmented lesion* OR mel-
                                                               LM and LMM on the Head and Neck
anoma:ti,ab OR “lentigo maligna” OR “lichen planus like
keratos*” OR “solar lentigo” OR “seborrheic keratos*”          The following extra-facial dermoscopy features: pseudo-
OR ‘seborrheic keratosis’/exp OR ‘melanoma’/exp OR “pig-       pods, radial streaming, blue white veil, irregular blotches,
mented bowen? disease” OR “pigmented actinic keratos*”         scar-like depigmentation and atypical pigment network were
OR “basal cell carcinoma*” OR “ squamous cell carci-           recorded in low frequencies, (Table 2) [9]. In some studies
noma*” OR ‘basal cell carcinoma’/exp OR ‘squamous cell         the criteria of extra-facial LMM were found in only 52.4%
carcinoma’/exp                                                 of cases [17]. The typical clinical presentation is commonly a
    Head/neck                                                  flat pigmented macule resembling other differentials includ-
    Head/exp OR Neck/exp OR Head:ti,ab OR neck:ti,ab           ing PAK/pBD/pIEC, LPLK, SL and SK [14,15].
OR face:ti,ab OR scalp:ti,ab                                      The common reported dermoscopic features of facial
    (TITLE-ABS (dermoscop* OR dermatoscop*) ) AND              melanoma were (Figure 1):
(TITLE-ABS (‘pigmented AND nevus’ OR pigmented AND
lesion* OR melanoma OR “lentigo maligna” OR “lichen            • Two or less colors and
planus like keratos*” OR “solar lentigo” OR “seborrheic        • Asymmetric pigmented follicular openings (APFO) or
keratos*” OR “pigmented bowen? disease” OR “pigmented            folliculotropism,
actinic keratos*” OR “basal cell carcinoma*” OR “squa-         • Brown colored globules and dots,
mous cell carcinoma*”) ) AND ( TITLE-ABS (head OR neck         • Signet-ring like structures,
OR scalp OR face) )                                            • A pattern of circles.
                                                               • Increased density of vascular network,
Results                                                        • Red rhomboid structures,
                                                               • Irregular dots (granularity or peppering),
A search of Embase and PubMed (Medline) database from          • Atypical dots and globules (gray, slate gray or blue),
January 2015 to January 2021 including all languages re-       • Rhomboid gray/black structures,
vealed a total of 324 studies. 165 were repeated (Embase
and PubMed), 143 Embase only and 16 Medline only. After           In some studies multiple irregular gray/blue dots, referred
reviewing all of the above publications twelve articles were   to as “granularity” or “peppering”, were found in 93.5% of
identified as relevant to this review.                         extra-facial melanoma, 26.5% of extra-facial benign lesions




        Table 2. Cengiz et al 2015. Frequency of analyzed criteria in head and neck melanomas.
             Dermoscopic Characteristics                   N. (k= Kappa coefficient)                      %
 Asymmetry in two axes                                             68 (k =1)                              63
 Atypical dots                                                     80 (k =1)                             74.1
 Radial streaming                                                32 (k =0.68)                            29.6
 Pseudopods                                                       8 (k =0.92)                             7.4
 Blue-white veil                                                   20 (k =1)                             18.5
 Mixed vascular pattern                                          44 (k = 0.92)                           40.7
 Scar-like depigmentation                                        64 (k = 0.87)                           59.3
 Rhomboidal Structures                                           32 (k = 0.85)                           29.6
 Atypical pigment network                                        26 (k = 0.92)                            24
 Pseudo-network                                                  32 (k = 0.84)                           29.6
 Asymmetric pigmented follicular openings                          56 (k =1)                             51.9
 Annular-granular pattern                                        20 (k = 0.72)                           18.5
 Colors (3 or more)                                              40 (k = 0.88)                            37
 Blotches                                                          8 (k = 1)                              7.4
 Increased density of vascular network                           35 (k = 0.95)                           32.4
 Red rhomboid structures                                         20 (k = 0.60)                           18.5
 Abrupt demarcation                                              11 (k = 0.76)                            10



6                                                                         Review | Dermatol Pract Concept. 2022;12(4):e2022194
[18], 32% of head and neck LMM and 15% of head and                accuracy of 0.72 for the diagnosis of LM seven criteria were
neck LM [9]. The blue-gray dots in dermoscopy were asso-          found significant [21]. These criteria were:
ciated with inflammatory cells, which were observed in both
LM and non-melanoma skin cancer (NMSC) [19]. Atypical             • Asymmetric pigmented follicular openings,
dots (gray or blue) and APFO were found in 74.1% and              • Rhomboid structures,
51.9% of cases respectively in some studies following the         • Target-like pattern,
Stolz progression model [20]. The Stolz progression model         • Perifollicular gray color,
suggested that the slate gray dots and globules are due to        • Dark blotches,
melanin loaded macrophages in the upper dermis. As me-            • Moth eaten borders and
lanocytes proliferate and invade the hair follicles and the       • Fingerprint-like structures.
dermis, features like asymmetrical follicular openings, rhom-
boid structures and complete obliteration of follicles are           In an attempt to differentiate between LM and PAK a
more dominant [18].                                               “newly developed algorithm” claimed a diagnostic accu-
   Granularity, in particular irregularly distributed, or pe-     racy of 86.5%, sensitivity of diagnosis of LM versus PAK of
ripherally distributed granularity, and that associated with      82.7%, specificity of 92.0%, positive predictive value (PPV)
red and white colour, was highly statistically significant        of 93.8% and negative predictive value (NPV) of 78.4%.
for melanoma (P < 0.001) (Figure1) [18]. Cengiz et al also        The eight statistically significant dermoscopic features for
supported Pralong et al in that facial melanoma frequently        differentiation of LM from PAK were [4]:
shows two or less colors compared to extra-facial melano-
mas [9,21]. Stolz et al, Pralong et al and Cengiz et al found     • Light brown color,
head and neck melanoma specific features to be two or less        • A structureless zone, varying in color from brown/tan
colors, increased density of vascular network, red rhomboid         to black,
structures, low frequency of irregular dots, the presence of      • In focus discontinuous brown lines,
a pseudo-network, asymmetric pigmented follicular open-           • Brown-to-gray incomplete circles,
ings, signet-ring like structures and annular-granular pattern    • A brown or black structureless zone obscuring hair
[9,20,21].                                                          follicles,
   An irregular distribution of globules and brown color of       • A brown (tan) eccentric structureless zone,
globules/dots in head and neck dermoscopy were associated         • A blue structureless zone and scales.
with LM in 94% and 100% of cases compared to 40% and
8% respectively in NMSC [19]. In other studies, irregular            The features found to contribute the most to a diagnosis
dots/globules were found in 76.2% of neck melanomas [17].         of LM were:
When using reflectance confocal microscopy (RCM) these
brown globules and dots correspond to melanocytic nests,          • Structureless zones ranging from brown/tan to black,
atypical cells and pagetoid nests in LM. In NMSC they cor-        • Blue structureless zones,
responded to interfollicular dendritic cells and follicular hy-   • Brown to black structureless zones obscuring hair fol-
perkeratosis [19].                                                  licles and
   The dermoscopic pattern of circles strongly indicated          • Incomplete brown to gray circles.
facial melanoma (LM), whereas for basal cell carcinoma
it is often a pattern of clods (Figure 1) [1]. In the presence       On the other hand the features suggestive of PAK were
of dermoscopic gray structures, the relative risk for ma-         (Figure 4):
lignancy is 2.2. Other studies found that gray color was
recorded in 81% of neck melanomas and that gray color/            • The occurrence of light structureless zones,
gray circles on the face, in particular if it was irregularly     • Brown (tan) eccentric scales and
distributed, was the main clue to an early diagnosis of           • In focus brown discontinuous lines.
LM [17,22]. Folliculotropism, defined as the location of
atypical melanocytes towards hair follicle infundibula, is        Clinical and dermoscopic features of
a histopathological feature of LM/LMM. This presents in
                                                                  PAK, pBD and pIEC
the form of gray rhomboid structures or gray circles. Gray
circles represent deeper involvement of the hair follicle in-     The main reported dermoscopic features of PAK, pBD and
fundibula [16].                                                   pIEC (Figure 4) were:
   Multiple models have been proposed to predict LM
[4,21]. In a multivariate logistic regression model with an       • Perifollicular erythema or red pseudo-network,



Review | Dermatol Pract Concept. 2022;12(4):e2022194                                                                        7
• White to yellow surface scale,                                       strong dermoscopic clue to pIEC shared with PAK in the
• Linear wavy vessels around hair follicles,                           head and neck [24]. That description corresponded to the
• Hair follicular openings surrounded by white halo,                   evident follicles described [2]. These dermoscopic findings
• Evident follicles or follicular or keratotic plugs,                  were significantly positive for actinic keratosis in other
• Rosette sign (four dot clods, when polarized light dermos-           studies [24], in addition to the rosette sign (also called four
    copy is used) and                                                  dot clods, seen with polarized light dermoscopy), large
• Sharply demarcated borders.                                          ­irregular linear vessels surrounding hair follicles and periph-
                                                                       eral pigmentation [25]. Serpentine vessels were present in
     In non-pigmented facial actinic keratosis (AK) four der-          almost half of the cases of pIEC head and neck compared
moscopic features were recorded [22], notedly (Figure 4):              to coiled vessels in pIEC elsewhere [24]. A combination of
                                                                       red pseudo-network, hair follicular opening surrounded by a
• Erythema      surrounding     the    hair   follicles   or   red     white halo and follicular plugs has been predicted to have a
    pseudo-network (95%),                                              sensitivity of 90.7%, specificity of 81.82%, PPV of 90.70%
• White to yellow surface scale (85%),                                 and a NPV of 81.82% (Figure 6) [25].
• Linear wavy vessels around hair follicles (81%) and                      For PAK/pBD scales show a PPV of 72.2% (specificity of
• Hair follicle openings filled with yellow keratotic plugs            94.2%), white circles a PPV of 68.8% (specificity of 94.2%)
    (66%) and/or surrounded by white halo (100%).                      and sharply demarcated borders a PPV of 44.2% (specific-
                                                                       ity of 86.0%), (Figure 6 and Table 3) [1]. The absence of
     These features collectively gave a picture of a “straw-           scales in pigmented macules on the head and neck in combi-
berry pattern”, (Figures 4 and 6).                                     nation with multiple colours with brown being present in all
     Actinic keratoses tend to present as multiple macules on          cases, as well pink, white and gray dominated in pigmented
the same patient suggesting a “signature” pattern [22]. In             intraepidermal carcinoma (pIEC) in that location as per In-
lighter skin Fitzpatrick types these are usually non-pigmented         skip et al compared to Cameron et al [6,24]. In some studies,
AK while on darker skins they are pigmented [23]. Another              PAK/pBDs/pIEC had incomplete circles reported in 73.1% of
clue to PAK on head and neck were “evident follicles” which            cases compared to 71.3% for melanoma, nil reported circle
were “visible follicles without pigmentation” and “projected           in circle or double circles, nil reported gray structures, rhom-
as the dominant dermatoscopic feature” [2]. “Non-pig-                  boid structures in 94.7% compared to 91.7% in melanoma,
mented follicles associated with either interfollicular pig-           nil dotted, serpentine or branched vessels, nil ulcerations and
ment, interfollicular erythema or both” was considered a               86.0% well demarcated margins, (Table 3 and Figure 6) [1].




Figure 6. Macroscopy - Left side - A 43-year-old male with a pink, slightly scaly lesion located on the left temple. Dermoscopy - Right
side - Dermoscopy features include a ‘strawberry’ appearance, with white-to-yellow follicular keratotic plugs (ellipse) surrounded by a
whitish halo, and background erythema/red pseudo-network. In addition, 4-dot-structures (circles) are seen in some parts of the lesion,
which when coalescing they form white complete circles (arrow). In parts of the lesion white lines are seen which are different from hairs
(squares)-Fotofinder dermoscopy, Medicam 1000, magnification x20. Diagnosis: actinic keratosis.




8                                                                                  Review | Dermatol Pract Concept. 2022;12(4):e2022194
    Table 3. Tschandl et al 2015. Diagnostic indices of dermatoscopic clues to flat malignant facial
                    lesions. Numbers in braces depict 95% confidence intervals.
                    RR (relative         PPV (positive         NPV (negative
                        risk)          predictive value)      predictive value)         Sensitivity              Specificity
 Melanoma
 Any gray          8.9 ( 1.2–64.7)     13.3% (8.6–19.3)       98.5% (91.9–99.8)     95.8% (78.8–99.3)        30.6% (24.5–37.2)
 structure
 Vessels as dots   3.5 (1.1–11.8)      33.3% (5.3–77.3)       90.6% (86.1–94.0)      8.3% (1.3–27.0)         98.1% (95.3–99.5)
 Incomplete         3.0 (1.4–6.5)      18.4% (10.5–29.0)      93.9% (89.1–97.0)     58.3% (36.7–77.9)        71.3% (64.8–77.2)
 circles
 Gray circles       4.6 (2.2–9.7)      26.5% (15.0–41.1)      94.2% (89.9–97.1)     54.2% (32.8–74.4)        83.3% (77.7–88.0)
 Rhomboids          2.0 (0.7–5.3)      18.2% (5.3–40.3)       90.8% (86.2–94.3)     16.7% (4.8–37.4)         91.7% (87.2–95.0)
 Circle in a       2.0 (0.3–12.3)      20.0% (3.3–71.2)       90.2% (85.7–93.7)      4.2% (0.7–21.2)         98.1% (95.3–99.5)
 circle/double
 circle
 Basal cell carcinoma
 Any gray          7.7 (1.1–56.6)      11.6% (7.2–17.3)       98.5% (91.9–99.8)     95.2% (76.1–99.2)        30.1% (24.1–36.7)
 structure
 Branched          17.8 10.5– 30.3 100.0% (62.9–100.0) 94.4% (90.6–97.0)            38.1% (18.1–61.6) 100.0% (98.3–100.0)
 vessels
 Serpentine        12.2 (6.7–22.1)     83.3% (36.1–97.2)      93.2% (89.1–96.0)     23.8% (8.3–47.2)         99.5% (97.5–99.9)
 vessels
 Ulceration        11.7 (6.0–22.7)     66.7% (35.0–89.9)      94.3% (90.5–96.9)     38.1% (18.2–61.6)        98.2% (95.4–99.5)
 Pigmented actinic keratosis/ Bowen disease
 White circles      3.0 (2.2–4.3)      68.8% (50.0–83.9)      77.4% (71.1–82.9)     31.9% (21.2–44.2)        94.2% (89.5–97.2)
 Sharply            1.7 (1.2–2.6)      44.2% (29.1–60.1)      74.6% (68.0–80.5)     27.5% (17.5–39.6)        86.0% (79.8–90.8)
 demarcated
 border
 Incomplete         1.7 (1.1–2.5)      39.5% (28.5–51.4)      76.2% (69.0–82.5)     43.5% (31.6–56.0)        73.1% (65.8–79.6)
 circles
 Rhomboids          2.3 (1.5–3.5)       59.1 (36.4–79.3)      74.3% (68.0–80.0)     18.8% (10.4–30.1)        94.7% (90.2–97.6)
 Four-dot clod      2.1 (1.0–4.5)      60.0% (15.4–93.5)      71.9% (65.7–77.6)      4.3% (1.0–12.2)         98.8% (95.8–99.8)
 Scale              3.4 (2.5–4.8)      72.2% (54.8–85.8)      78.9% (72.7–84.3)     37.7% (26.3–50.2)        94.2% (89.5–97.2)




Conclusions                                                       the head and neck. These site-specific areas include the ears,
                                                                  nose, cheeks, scalp and neck. The development of specific al-
The accurate diagnosis of LM and LMM is paramount for             gorithms based on deep learning models (eg integrated scor-
their early appropriate management. The differential diagno-      ing classifiers) could be of great help in differentiating LM/
sis is variable. Different studies have compared different der-   LMM of the head and neck from their simulators in clinical
moscopic features of LM, LMM, PAK, pBD and pIEC. Not all          practice [26].This would benefit from further studies.
features were compared similarly. Some studies documented
sensitivity and specificity while other publications listed the
percentage of lesions showing the feature. Some compared
                                                                  References
positive predictive value (PPV) and negative predictive value     1. Tschandl P, Rosendahl C, Kittler H. Dermatoscopy of
(NPV) of the dermoscopy features. To date the used termi-            flat pigmented facial lesions. J Eur Acad Dermatol Vene-
nology is not unified in spite of some frequently used terms.        reol. 2015;29(1):120-127. DOI: 10.1111/jdv.12483. PMID:
                                                                     24661420.
Further studies are needed to agree on the criteria specific
                                                                  2. Lallas A, Tschandl P, Kyrgidis A, et al. Dermoscopic clues to
to each diagnosis, namely LM, LMM, PAK, pBD and pIEC.                differentiate facial lentigo maligna from pigmented actinic ker-
Furthermore, according to the current literature, there is a         atosis. Br J Dermatol. 2016;174(5):1079-1085. DOI: 10.1111/
gap in the knowledge of site-specific dermoscopic features on        bjd.14355. PMID: 26784739.




Review | Dermatol Pract Concept. 2022;12(4):e2022194                                                                               9
 3. Juhász ML, Marmur ES. Reviewing challenges in the diagnosis             16. Dika E, Lambertini M, Patrizi A, et al. Folliculotropism in head
    and treatment of lentigo maligna and lentigo-maligna melanoma.              and neck lentigo maligna and lentigo maligna melanoma. J Dtsch
    Rare Cancers Ther. 2015;3(1):133-145. DOI: 10.1007/s40487-                  Dermatol Ges. 2021;19(2):223-229. DOI: 10.1111/ddg.14311.
    015-0012-9. PMID: 27182482. PMCID: PMC4837936.                              PMID: 33166059.
 4. Micantonio T, Neri L, Longo C, et al. A new dermoscopic algorithm       17. Borsari S, Pampena R, Raucci M, et al. Neck Melanoma:
    for the differential diagnosis of facial lentigo maligna and pig-           Clinical, Dermoscopic and Confocal Features. Dermatology.
    mented actinic keratosis. Eur J Dermatol. 20181;28(2):162-168.              2020;236(3):241-247. DOI: 10.1159/000503284. PMID:
    DOI: 10.1684/ejd.2018.3246. PMID: 29620004.                                 31707398.
 5. Akay B, Kocyigit P, Heper A, Erdem C. Dermatoscopy of flat pig-         18. Braun R, Gaide O, Oliviero M, et al. The significance of mul-
    mented facial lesions: diagnostic challenge between pigmented actinic       tiple blue‐grey dots (granularity) for the dermoscopic diagno-
    keratosis and lentigo maligna. Br J Dermatol. 2010;163(6):1212-             sis of melanoma. Br J Dermatol. 2007;157(5):907-913. DOI:
    1217. DOI: 10.1111/j.1365-2133.2010.10025.x. PMID: 21083845.                10.1111/j.1365-2133.2007.08145.x. PMID: 17725673.
 6. Cameron A, Rosendahl C, Tschandl P, Riedl E, Kittler H. Der-            19. Guida S, Farnetani F, De Pace B, et al. Flat-pigmented facial le-
    matoscopy of pigmented Bowen’s disease. J Am Acad Dermatol.                 sions without highly specific melanocytic dermoscopy features:
    2010;62(4):597-604. DOI: 10.1016/j.jaad.2009.06.008. PMID:                  the role of dermoscopic globules and dots in differential diag-
    20079953.                                                                   nosis with corresponding reflectance confocal microscopy sub-
 7. Barnes L. Surgical Pathology of the Head and Neck. vol 3. CRC               strates. J Eur Acad Dermatol Venereol. 2020;34(3):e153-e156.
    Press; 2001:1819-24                                                         DOI: 10.1111/jdv.16079. PMID: 31729773.
 8. Fadaki N, Li R, Parrett B, et al. Is head and neck melanoma             20. Stolz W, Schiffner R, Burgdorf WH. Dermatoscopy for facial pig-
    different from trunk and extremity melanomas with respect to                mented skin lesions.Clin Dermatol. 2002;20(3):276-278. DOI:
    sentinel lymph node status and clinical outcome? Ann Surg On-               10.1016/s0738-081x(02)00221-3. PMID: 12074867.
    col. 2013;20(9):3089-3097. DOI: 10.1245/s10434-013-2977-7.              21. Pralong P, Bathelier E, Dalle S, Poulalhon N, Debarbieux S,
    PMID: 23649930.                                                             Thomas L. Dermoscopy of lentigo maligna melanoma: re-
 9. Cengiz FP, Cengiz AB, Emiroglu N, Comert E, Wellenhof RH. Der-                port of 125 cases. Br J Dermatol. 2012;167(2):280-287. DOI:
    moscopic and clinical features of head and neck melanoma. An                  10.1111/j.1365-2133.2012.10932.x. PMID: 22404578.
    Bras Dermatol. 2015;90(4):488-493. DOI: 10.1590/abd1806-                22.   Tiodorovic-Zivkovic D, Zalaudek I, Lallas A, Stratigos AJ, Piana
    4841.20153341. PMID: 26375217. PMCID: PMC4560537.                             S, Argenziano G. The importance of gray color as a dermoscopic
10. Cohen LM. Lentigo maligna and lentigo maligna melanoma. J                     clue in facial pigmented lesion evaluation: a case report. Derma-
    Am Acad Dermatol. 1995;33(6):923-936. DOI: 10.1016/0190-                      tol Pract Concept. 2013;3(4):37-39. DOI: 10.5826/dpc.0304a09.
    9622(95)90282-1. PMID: 7490362.                                               PMID: 24282663. PMCID: PMC3839831.
11. McKenna JK, Florell SR, Goldman GD, Bowen GM. Lentigo                   23.   Giacomel J, Lallas A, Argenziano G, Bombonato C, Zalaudek
    maligna/lentigo maligna melanoma: current state of diagno-                    I. Dermoscopic “signature” pattern of pigmented and non-
    sis and treatment. Dermatol Surg. 2006;32(4):493-504. DOI:                    pigmented facial actinic keratoses. J Am Acad Dermatol.
    10.1111/j.1524-4725.2006.32102.x. PMID: 16681656.                             2015;72(2):e57-e59. DOI: 10.1016/j.jaad.2014.10.043. PMID:
12. Bowen AR, Thacker BNP, Goldgar DE, Bowen GM. Immuno-                          25592364.
    histochemical staining with Melan‐A of uninvolved sun‐dam-              24.   Inskip M, Cameron A, Akay BN, et al. Dermatoscopic features
    aged skin shows features characteristic of lentigo maligna.                   of pigmented intraepidermal carcinoma on the head and neck.
    Dermatol Surg. 2011;37(5):657-663. DOI: 10.1111/j.1524-                       J Dtsch Dermatol Ges. 2020;18(9):969-976. DOI: 10.1111/
    4725.2011.01946.x. PMID: 21446989.                                            ddg.14220. PMID: 32841518.
13. Kittler H, Pehamberger H, Wolff K, Binder M. Diagnostic ac-             25.   Li W, Zhang C. 180 The investigation of dermoscopy in differen-
    curacy of dermoscopy. Lancet Oncol. 2002;3(3):159-165. DOI:                   tial diagnosis of facial actinic keratosis. Journal of Investigative
    10.1016/s1470-2045(02)00679-4. PMID: 11902502.                                Dermatology. 2017;137(5):S31.
14. Massone C, Di Stefani A, Soyer HP. Dermoscopy for skin can-             26.   Tognetti L, Cevenini G, Moscarella E, et al. Validation of an inte-
    cer detection. Curr Opin Oncol. 2005;17(2):147-153. DOI:                      grated dermoscopic scoring method in an European teledermos-
    10.1097/01.cco.0000152627.36243.26. PMID: 15725920.                           copy web platform: the iDScore project for early detection of
15. Megahed M, Schön M, Selimovic D, Schön MP. Reliability of diag-               melanoma. J Eur Acad Dermatol Venereol. 2020;34(3):640-647.
    nosis of melanoma in situ. Lancet. 2002;359(9321):1921-1922.                  DOI: 10.1111/jdv.15923. PMID: 31465600.
    DOI: 10.1016/S0140-6736(02)08741-X. PMID: 12057558.




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