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Research  |  Dermatol Pract Concept 2015;5(4):8 31

DERMATOLOGY PRACTICAL & CONCEPTUAL
www.derm101.com

Introduction

Early detection of melanoma is crucial to improve survival 

[1]. Melanoma may be clinically but also dermoscopically 

indistinguishable from other pigmented skin lesions, espe-

cially in incipient and small lesions [2].

Several strategies such as the ABCD(E) acronym [3,4], the 

“ugly duckling sign” [5] or the EFG [6], just to mention a few, 

have been proposed to enhance clinical recognition of atypi-

cal lesions that should undergo excision or close monitoring, 

but it usefulness in the detection of melanoma at a curable 

stage is questionable since only evolved lesions fulfil clinical 

criteria [7,8].

Dermoscopy has shown to improve melanoma detection 

by allowing the visualization of diagnostic criteria not visible 

to the naked eye, and its routine use for the evaluation of 

skin lesions is recommended in most of the clinical guidelines 

worldwide [9]. The use of sequential digital dermoscopy for 

the comparison of current and previous images in search of 

subtle changes over time has shown to be helpful in the diag-

nosis of early melanomas that might lack of specific criteria 

for malignancy [10].

Herein we present a series of melanomas located on the 

leg with a diameter less than 5 mm measured on relaxed skin 

before excision. This study reports the dermoscopic clues for 

early recognition of these lesions and highlights importance 

of weighing the personal and familial history as well as the 

clinical context.

Case presentations
The cases are presented in Table 1. The 8 melanomas cor-

responded to 7 patients, most females (7/8), with a mean 

age of 42.5 years (range 35-53 years). Four melanomas were 

detected during routine nevi control and 4 were detected due 

to changes during digital follow-up; the melanoma was not 

the reason for the patient´s consultation. Cases 6 and 7 cor-

responded to the same patient, a 35-year-old female carrier 

of G101W mutation in CDKN2A.

Clinical characteristics are shown in Table 2. All melano-

mas were located on the legs, 7 in the calf and 1 in the thigh. 

All melanomas have a diameter lower than 5 mm, with a 

mean of 3.7 mm (range 2.5-4.5 mm). According to naked eye 

examination only 2 of 8 melanomas had irregular borders, 

A series of small-diameter melanomas on the legs: 
dermoscopic clues for early recognition

Gabriel Salerni 1,2, Carlos Alonso1,2, Ramón Fernández-Bussy1

1 Hospital Provincial del Centenario de Rosario, Argentina. Faculty of Medicine, Universidad Nacional de Rosario, Argentina
2 Diagnóstico Médico Oroño, Rosario, Argentina

Key words: melanoma; dermoscopy; atypical mole syndrome; follow-up; imaging techniques

Citation: Salerni G, Alonso C, Fernández-Bussy R. A series of small-diameter melanomas on the legs: dermoscopic clues for early 
recognition. Dermatol Pract Concept 2015;5(4):8. doi: 10.5826/dpc.0504a08

Received: June 29, 2015; Accepted: July 4, 2015; Published: October 31, 2015

Copyright: ©2015 Salerni et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, 
which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: None.

Competing interests: The authors have no conflicts of interest to disclose.

All authors have contributed significantly to this publication.

Corresponding author: Gabriel Salerni, MD, PhD, Urquiza 3100, CP: S2002KDR, Rosario, Argentina. Tel. +54 341 4398586. Email: 
gabrielsalerni@hotmail.com

mailto:gabrielsalerni@hotmail.com


32 Research  |  Dermatol Pract Concept 2015;5(4):8

while case 8 additionally displayed changes in dermoscopic 

structures and colors (Figure 3).

All melanomas corresponded to superficial spreading his-

tologic type. Most melanomas (6/8) were in situ. Two mela-

nomas, corresponding to cases 1 and 8, were invasive with a 

Breslow thickness of 0.2 (Figure 4) and 0.35 mm respectively.

Discussion

Strategies aimed at recognition of suspicious lesions may have 

little impact in the diagnosis of small melanomas. The ABCD 

rule [3], originally designed 30 years ago and revised in 2004 

[11] when the E criterion (for Evolution) was included, fails 

to recognize the existence of small-diameter melanoma, i.e., 

melanomas less than 6 mm in diameter.

and 3 out of 8 were asymmetric and had multiple colors. 

In only 2 cases the patients were able to report a history of 

change, in both cases the lesions were reported as new. In 4 

cases the patients referred the lesion as stable, and in 2 cases 

the patients were unaware of the lesion (Figure 1).

Dermoscopy evaluation was based on pattern analysis; 

dermoscopic features are shown in Table 3. Upon dermoscopy 

5 melanomas were asymmetric; 3 lesions displayed only 1 

color, 2 melanomas had 2 colors and 3 displayed 2 or more 

colors. Reticular pattern and the presence of atypical pig-

ment network were the most frequent features, seen in 7 of 8 

melanomas (Figure 2).

Four melanomas were detected due to changes during 

digital follow-up (cases 5 to 8). In 3 melanomas (cases 5, 6 

and 7) the only change detected was asymmetric enlargement, 

TABLE 1. Cases presentations

Case Age Gender
Form of diagnosis

FH MM PH MM Multiple MM AMS
MMC MMRC MMDD

1 44 F   ✓ ✓ ✓

2 52 F   ✓

3 35 F   ✓ ✓

4 45 M   ✓

5 43 F   ✓ ✓ ✓ ✓

6 35 F   ✓ ✓ ✓ ✓ ✓

7 35 F   ✓ ✓ ✓ ✓ ✓

8 53 F   ✓ ✓

MMC: Melanoma reason for consultation; MMRC: Melanoma routine control; MMDD: melanoma digital dermoscopy; 
FH MM: familial history of melanoma; PH MM: personal history of melanoma; AMS: Atypical mole syndrome

TABLE 2. Clinical characteristics

Case

ABCD (E)

Asymmetry 
(A)

Irregular 
borders (B)

Multiple 
colours 

(C)

Diameter (D)
History of change 

(Evolution, E)Diameter >6 
mm

Diameter 
(mm)

1 3.1 ✓

2 ✓ ✓ 2.5

3 ✓ ✓ ✓ 4.5 Unknown

4 3.6 ✓

5 3.3

6 4.3

7 4.0

8 ✓ ✓ ✓ 4.5 Unknown



Research  |  Dermatol Pract Concept 2015;5(4):8 33

series, the melanoma was not the reason for patient’s consul-

tation; the strict application of the ABCD rule for appraisal of 

lesions that may need to be further examined by a specialist 

would have led to missing these melanomas. Even though the 

inclusion of E, for Evolution, has improved the recognition of 

melanoma by emphasizing change over time as an important 

The D criterion has been a matter of controversy since 

all melanomas are smaller than 6 mm in early stages and a 

significant proportion of melanomas may be smaller than 6 

mm at the time of diagnosis. As stated by Kittler, the limit of 

6 mm is not a biological minimum size of melanomas, but the 

lower limit for the applicability of the ABCD rule [12]. In our 

Figure 1. Clinical images of cases 1 to 8 (a to h). Cases 1 to 4 (a to d) corresponded to melanomas detected during routine nevi control while 
cases 5 to 8 (e to h) corresponded to melanomas detected during digital follow-up; cases 6 and 7 (f and g) corresponded to the same patient. 
None of the lesions fulfilled clinical criteria for suspicion of melanoma. [Copyright: ©2015 Salerni et al.]



34 Research  |  Dermatol Pract Concept 2015;5(4):8

Figure 2. Dermoscopic features of cases 1 to 8 (a to h). Reticular pattern was seen in all cases but in case 5 (e). In cases 1 to 4 (a to d) and in 
case 8 (h) the presence of atypical pigment network was observed. Cases 1, 4 and 5 (a, d and e) showed pseudopods at the periphery. Cases 
6 and 7 displayed typical pigment network with hypo pigmented irregular areas. [Copyright: ©2015 Salerni et al.]

additional criterion in the differentia-

tion of melanoma from benign lesions, 

in only 2 cases the patients were able 

to report a history of change; in both 

cases the lesions were reported as new. 

We found that patients may find it dif-

ficult to detect the occurrence of new 

small lesions as well as clinical changes 

in pre-existing small lesions.

Unlike nodular type, superficial 

spreading and lentiginous melanomas 

usually experiment a variable radial 

growth phase before invading the 

underlying dermis. Nevertheless, small-

diameter superficial spreading melano-

mas with vertical growth phase have 

been reported [13,14]. In our series, 2 

invasive melanomas with a diameter of 

3.1 and 4.5 mm were observed, high-

lighting that even very small lesions may 

have metastatic potential.

The diagnosis of small-diameter 

melanomas poses difficulties because 

the dermoscopic features of small mela-

nomas have been reported infrequently. 

According to our findings, even in 

small lesions dermoscopic clues might 

allow early recognition. Reticular pat-

tern and the presence of atypical pig-

ment network was the most common 

dermoscopic feature (7/8) followed by 

radial streaks / pseudopods (2/8). It is 

recommended that dermoscopy should 

be performed in all lesions, and not just 

for those suspicious from the clinical 

point of view, since clinical pre-selection 

of lesions for dermoscopic examination 

is associated with a loss of lesions that 

might require either surgical excision or 

follow-up examinations [15].

Four melanomas were detected due 

to changes during digital of high-risk 

melanoma patients, increase in size 

with no further significant change were 

observed in 3 cases; 1 case displayed 

changes in shape, structures and pig-

mentation. This supports the fact that 

digital follow-up allows for the detec-

tion of early melanoma, when specific 

structures or criteria for malignancy 

may not be present yet [7,8].

In a recent study Carrera et al. [16] 

addressed special attention to melano-

mas of the legs. As in our series, in the 

dermoscopic analysis none of the cases 

showed a multi-component pattern, or 

marked asymmetry in structure or pig-



Research  |  Dermatol Pract Concept 2015;5(4):8 35

Figure 3. Dermoscopic changes leading to excision in cases 5 to 8. Increase in size with no further significant change were observed in cases 
5 to 7 (first, second and third row respectively). In case 8 (fourth row) dermoscopic changes were more evident, with changes in shape, 
structures and pigmentation. [Copyright: ©2015 Salerni et al.]



36 Research  |  Dermatol Pract Concept 2015;5(4):8

99 consecutive primary melanomas. Dermatol Pract Concept. 
2014;4(4):7.

 8.  Salerni G, Lovato L, Carrera C, et al. Melanomas detected in 
follow-up program compared with melanomas referred to a 
melanoma unit. Arch Dermatol. 2011;147(5):549-55

 9.  Australian Cancer Network (ACN). Clinical practice guidelines 
for the management of melanoma in Australia and New Zealand 
(2008). Available from: http://www.nhmrc.gov.au/_files_nhmrc/
publications/attachments/cp111.pdf. Accessed June 2015.

10.  Salerni G, Terán T, Puig S, et al. Meta-analysis of digital dermos-
copy follow-up of melanocytic skin lesions: a study on behalf 
of the International Dermoscopy Society. J Eur Acad Dermatol 
Venereol. 2013;27(7):805-14.

11.  Abbasi NR, Shaw HM, Rigel DS, et al. Early diagnosis of cu-
taneous melanoma: revisiting the ABCD criteria. JAMA. 
2004;292(22):2771-6.

12.  Kittler H, Rosendahl C, Cameron A, Tschandl P. Dermatoscopy—
An Algorithmic Method Based on Pattern Analysis. Austria: 
Facultas.wuv, 2011.

13.  Pellizzari G, Magee J, Weedon D, et al. A tiny invasive melanoma: 
a case report with dermatoscopy and dermatopathology. Derma-
tol Pract Concept. 2013;3(2):6.

14.  Bono A, Tolomio E, Trincone S, et al. Micro-melanoma detection: 
a clinical study on 206 consecutive cases of pigmented skin lesions 
with a diameter < or = 3 mm. Br J Dermatol. 2006;155(3):570-3.

15.  Seidenari S, Longo C, Giusti, et al. Clinical selection of melano-
cytic lesions for dermoscopy decreases the identification of sus-
picious lesions in comparison with dermoscopy without clinical 
preselection. Br J Dermatol. 2006;154(5):873–9.

16.  Carrera C, Palou J, Malvehy J, et al. Early stages of melanoma on 
the limbs of high-risk patients: clinical, dermoscopic, reflectance 
confocal microscopy and histopathological characterization for 
improved recognition. Acta Derm Venereol. 2011;91(2):137-46.

mentation, emphasizing the importance of finding other 

dermoscopic features in these early lesions.

We report a series of small-diameter melanomas of the 

legs that did not meet the clinical criteria for suspicion. The 

routinely use of dermoscopy in the evaluation of skin lesions 

and digital dermoscopy in the monitoring of high-risk indi-

viduals provided crucial information for early recognition of 

these lesions that might have been overlooked assessed solely 

by the naked eye.

References
 1.  Kopf AW, Welkovich B, Frankel RE, et al. Thickness of malignant 

melanoma: global analysis of related factors. J Dermatol Surg 
Oncol. 1987;13(4):345-20.

 2.  Puig S, Argenziano G, Zalaudek I, et al. Melanomas that failed 
dermoscopic detection: a combined clinicodermoscopic approach 
for not missing melanoma. Dermatol Surg. 2007;33(10):1262-73.

 3.  Friedman RJ, Rigel DS, Kopf AW. Early detection of malignant 
melanoma: the role of physician examination and self-examina-
tion of the skin. CA Cancer J Clin. 1985;35(3):130-51.

 4.  Rigel DS, Friedman RJ. The rationale of the ABCDs of early 
melanoma. J Am Acad Dermatol. 1993;29:1060-1.

 5.  Grob JJ, Bonerandi JJ. The ‘ugly duckling’ sign: identification of 
the common characteristics of nevi in an individual as a basis for 
melanoma screening. Arch Dermatol. 1998;134(1):103-4

 6.  Kelly JW, Chamberlain AJ, Staples MP, et al. Nodular melanoma. No 
longer as simple as ABC. Aust Fam Physician. 2003;32(9):706–9.

 7.  Salerni G, Terán T, Alonso C, Fernández-Bussy R. The role of 
dermoscopy and digital dermoscopy follow-up in the clinical 
diagnosis of melanoma: clinical and dermoscopic features of 

Figure 4. Histologic image of case 1, showing proliferation of atypical melanocytes at the dermo-epidermal junction with pagetoid spread 
and focal invasion of dermis. Diagnosis: superficial spreading melanoma, Breslow 0.2 mm. Histologic images courtesy of Mario Gorosito. 
[Copyright: ©2015 Salerni et al.]

http://www.ncbi.nlm.nih.gov/pubmed/?term=Pellizzari%20G%5BAuthor%5D&cauthor=true&cauthor_uid=23785644
http://www.ncbi.nlm.nih.gov/pubmed/?term=Magee%20J%5BAuthor%5D&cauthor=true&cauthor_uid=23785644
http://www.ncbi.nlm.nih.gov/pubmed/?term=Weedon%20D%5BAuthor%5D&cauthor=true&cauthor_uid=23785644
http://www.ncbi.nlm.nih.gov/pubmed/3921200