Dermoscopy of Melanocytic Lesions in Children
Total Page:16
File Type:pdf, Size:1020Kb
Dermoscopy of Melanocytic Lesions in Children Alexander C. Katoulis Assoc. Professor of Dermatology and Venereology 2nd Department of Dermatology and Venereology, National and Kapodistrian University of Athens, Medical School, “Attikon” General University Hospital 19th Annual Meeting of the European Society for Pediatric Dermatology, Dubrovnic, Croatia, May 4, 2019 Disclosure of conflicts of interest & relationships with industry Prof. Alexander C. Katoulis, MD, PhD I have no conflicts of interest to declare I do not have any relevant relationships with industry Dermoscopy In vivo, non-invasive diagnostic technique Light source (polarized or non-polarized) + magnifying lens (x10) Enables visualization of patterns, structures and colors Bridge between clinical examination and histopathology Improves diagnostic accuracy by 30% Needs training and experience DERMOSCOPY: GENERAL CONSIDERATIONS Dermoscopy for melanocytic lesions Improves diagnostic accuracy Improves both sensitivity and specificity Better detection of melanoma Fewer unnecessary biopsies or excisions Dermoscopy can pick out the few malignant lesions out of a huge number of benign lesions BENIGN LESIONS (NEVI) MALIGNANT LESIONS (MELANOMAS) Melanocytic lesions in children Cause particular concern to parents 30% of pediatric dermatologic consultations are due to concerns regarding nevi (Aguillera P et al, 2009) Concern is - disproportionate to the rare occurrence of pediatric melanoma - proportionate to the impact of a possible melanoma diagnosis in a child Dermoscopy in children It is the ideal tool for examining children Painless No special examining conditions necessary Sometimes its shape and light are even amusing for children Melanocytic lesions in children Benign Malignant Congenital nevi Malignant melanoma Blue nevus Spitzoid melanoma Acquired common and dysplastic nevi Halo nevus Spitz nevus Special types (irritated, recurring, combined) Special sites Diagnostic procedure History (personal, family) Asseement of risk factors History of the lesion Clinical examination Dermoscopy Other skin imaging techniques Histopathology= gold standard for definite diagnosis Main diagnostic algorithm: two steps Dermoscopic evaluation of a lesion • Dermoscopic features of melanocytic lesion: present YES or NO? Pigment network, globules, dots, radial streaks, pseudopods, blotch, regression, blue white, veil • Symmetry: YES or NO • Color: ONE or MORE • Pattern analysis: - Global pattern - Local dermoscopic features - Additional dermoscopic features: vessels, etc - Confounding features: scales, crusts, hair, etc. DERMOSCOPIC DIAGNOSIS DECISION: Excision – Follow up – No action Haliasos EC et al, Pediatr Dermatol 2013 Haliasos EC et al, Pediatr Dermatol 2013 Haliasos EC et al, Pediatr Dermatol 2013 Melanoma-specific dermoscopic criteria Dermoscopic features Atypical network associated with MM Atypical globules and dots No one is pathognomic Blotch/eccentric Their presence raise hyperpigmented area suspicion of MM Blue-white structures Concurrent evaluation of (elevated part) history, clinical and Regression (flat part) dermoscopic findings lead Reticular depigmentation to dermoscopic diagnosis and management decision Polymorphous vessels Crystalline structures HISTOPATHOLOGIC CORRELATES OF DERMOSCOPIC-SPECIFIC STRUCTURES HISTOPATHOLOGIC CORRELATES OF DERMOSCOPIC-SPECIFIC STRUCTURES Haliasos EC et al, Pediatr Dermatol 2013 If there is: -Asymmetry - Multiple colors - Global pattern does not conform to a benign pattern - Lesion reveals any of the melanoma-specific structures OR If a dermoscopic diagnosis of a benign lesion can not be made with confidence The lesion is suspicious and a biopsy should be performed DERMOSCOPY OF MELANOCYTIC LESIONS CONGENITAL MELANOCYTIC NEVI Congenital melanocytic nevi (CMN) Nevi present at birth or appearing within the first year of life (tardive) Persist throughout all life Result from errors in migration and proliferation of melanocytic progenitor cells during embryogenesis Are found in 1-6% of newborns (0.5-31.7%) (Price HN, Schaffer JV, 2010) Estimated incidence for giant CMN: 1 in 20,000- 500,000 live births Alikhan A et al, 2012 Clinical characteristics Flat or raised with well-demarcated borders Smooth, papillomatous or verrucous surface Light- to dark-brown color, variegation of color Often numerous terminal hair Over time may show variations in color, borders, and surface Giant CMN often have scattered smaller satellite CMN (Marghoob AA, 2002) Congenital melanocytic nevus Congenital melanocytic nevus (medium) Giant congenital melanocytic nevus Courtesy of Dr Vincenzo Piccolo, Naples, Italy Congenital melanocytic nevi (CMN) CMN are usually classified according to size* into: small (<1.5 cm), medium (1.5–20 cm), large (>20-40 cm), and giant or “garment” (≥40 cm) (Alikhan A et al, 2012) Patients with giant CMN and many satellite nevi are at greatest risk of developing cutaneous and extracutaneous melanoma and neurocutaneous melanocytosis * Projected adult size Dermoscopy of CMN Global pattern Local features Cobblestone (large Globules (regular, angulated globules)/ irregular) globular (head and Dots trunk) Pigment network Reticular (lower (regular, irregular) extremities) Multifocal perifolicular hypopigmentation Homogeneous Hyperpigmented zones Multicomponent (pseudomelanoma) Dermoscopy of CMN Additional features Confounding features Vessels (in up to 70%): Hair comma vessels, dotted Milia-like cysts vessels, serpentine Comedo-like openings (Haliasos EC et al, 2012) Cobblestone/globular pattern Hair Multicomponent pattern Perifollicular hypopigmentation Zones of hyperpigmentation (pseudomelanoma) Risk of melanoma development There is lack of consensus In studies, varies between 0.05% and 10.7% Depends mostly on: - size of the nevus - age of the patient In 6571 patients followed for mean 3.4-23.7 years, only 0.7% developed melanoma (median age at diagnosis 7 years, highest risk for giant CMN) (Krengel S et al, 2006) Melanoma arising in a small/medium CMN Low risk for small/medium CMN Lifetime risk estimated to be up to 1% Risk seems to be related to age: 0.7 per million for children < 10 years – 13.2 per million for adolescents 15-19 years MM tend to develop: - later in life (after childhood) - at the dermo-epidermal junction with SSM histology (Moscarella E et al, 2013) Dermoscopy can help in the early detection: appearance of new dermoscopic structures at the periphery of the lesion Melanoma arising in a small/medium CMN Haliasos EC et al, Pediatr Dermatol 2013 Melanoma arising in a small/medium CMN Melanoma arising in a CMN of a 14 years old child Courtesy of Dr Vincenzo Piccolo, Naples, Italy Melanoma arising in a CMN of a 11 years old child Courtesy of Dr Vincenzo Piccolo, Naples, Italy Melanoma arising in a large/giant CMN MM tends to develop: ❖ earlier in life - 1/3 of MM under 12 years is related to the presence of giant CMN (Bonifaci E et al, 2001) - risk is highest for giant CMN during childhood (Krengel S et al, 2006) ❖ deeper, below the dermo-epidermal junction with nodular melanoma histology (Marghoob AA, 2002) Clinically, is characterized by a growing nodule within the CMN Dermoscopically, features of intermediate/thick MM: blotch, blue-white veil, blue and black color, crystalline structures Dermoscopy cannot be relied upon for early identification Management Individualized to address risk for MM and aesthetic – psychosocial issues For small/medium CMN: early excision or regular clinical and dermoscopic follow up ± digital dermoscopy, yearly For large CMN: prophylactic early excision + follow up (for MM development outside of the nevus) Moscarella E et al, 2013 Nevus spilus Nevus spilus Nevus spilus Hyperpigmented patch studded with numerous macules and papules Speckled appearance Usually evident at birth Superficial variant of CMN Two subtypes: macular and papular Nevus spilus maculosus and papulosus Macular type: dark flat speckles evenly distributed on a light brown background (“polka-dot pattern” or “star map”) Papular type: speckles usually represent dermal melanocytic nevi or small CMN Occasionally, other AMN, Spitz nevi, blue nevi, and melanoma may arise (Cramer SF, 2001) Vidaurri-de la Cruz H, Hapel R, 2006 Dermoscopy of nevus spilus Homogeneous tan or a faint network as a background Dark brown or pink macules and papules within the nevus spilus with dermoscopic features corresponding to the type of nevus (Zalaudek I et al, 2006) Global pattern: homogeneous, reticular, globular or multi-component Local features: - macular speckles exhibit a reticular pattern - papular speckles manifest a globular pattern Nevus spilus Nevus spilus Malignant potential of nevus spilus The risk varies in the literature MM reported more commonly in the macular subtype (25% vs 10%) Propensity to develop Spitz nevi appears to be equal for both types Vidaurri-de la Cruz H, Hapel R, 2006; Hapel R, 2009 Amelanotic melanoma arising in a nevus spilus ACQUIRED MELANOCYTIC NEVI Acquired melanocytic nevi (AMN) Appear in early childhood and increase in numbers during adolescence (Stinco G et al, 2011) AMN are classified into: - common (junctional, dermal, compound) - atypical or dysplastic Common acquired melanocytic nevi Clinical characteristics Dermoscopic features ◼ Flat or slightly raised ◼ Global pattern (no ◼ Up to 5mm more than one): reticular, globular, ◼ Regular border homogenous ◼ Symmetry of shape ◼ Local features: regular ◼ 1-2 colors