Nevus azul celular con satelitosis y velo azul blanquecino simulando un melanoma, a propósito de un caso / Cellular blue nevus with satellitosis and blue veil whitish simulating a melanoma, purpose of a case

Los nevi azules son proliferaciones melanocíticas dendríticas benignas a nivel dérmico, congénitos o adquiridos, debido a un defecto migratorio embrionario de melanocitos a partir de la cresta neural. Se manifiestan clásicamente como una pápula, nódulo o placa de color azul o azul-gris. Muchos subtipos histológicos se han descrito, siendo los más comunes el nevus azul común, nevus azul celular y nevus azul combinado. Las formas esporádicas incluyen al nevus azul lineal, eruptivo, agminado y con satelitosis. La dermatoscopía característica muestra un patrón de pigmentación homogéneo monocromático azul o azul-grisáceo, con ausencia de otras estructuras. Sin embargo, se han descrito también patrones de pigmentación dicromáticos y multicromáticos, además de estructuras tales como red de pigmento, puntos, glóbulos, proyecciones radiadas, pseudópodos, áreas cicatriciales blanquecinas, patrón vascular y rosetas. El diagnóstico diferencial de los nevi azules incluye lesiones melanocíticas y no melanocíticas, benignas y malignas, destacando entre ellas el melanoma. Se presenta el caso de un paciente de sexo masculino de 30 años, portador de un nevus azul celular con cambios de rápida evolución, con desarrollo de lesiones satélites y un aspecto dermatoscópico sugerente de malignidad, simulando un melanoma.

Blue nevi are benign, congenital, or acquired, dermal dendritic melanocytic proliferations due to an embryonic migratory defect of melanocytes starting from the neural crest. They classically manifest as a blue or blue-gray papule, nodule, or plaque. Many histological subtypes have been described, including common blue nevus, cellular blue nevus and combined blue nevus. Sporadic forms include linear blue nevus, eruptive, agminate and with satellitosis. Characteristic dermoscopy shows a homogeneous monochromatic blue or steel-blue pigmentation pattern, with the absence of other structures. However, dichromatic and multichromatic pigmentation patterns have also been described, in addition to structures such as pigment network, dots, globules, streaks, pseudopods, whitish scar areas, vascular pattern and rosettes. Differential diagnosis of blue nevi includes melanocytic and non-melanocytic, benign and malignant lesions, most notably melanoma. The case of a 30-year-old male patient is presented, with a cellular blue nevus with rapidly evolving changes, with development of satellite lesions and a dermoscopic appearance suggestive of malignancy, mimicking melanoma.

Melanoma Ex Blue Nevus With GNA11 Mutation and BAP1 Loss: Case Report and Review of the Literature.

Cutaneous melanomas may demonstrate a variety of histopathological features and genetic abnormalities. Melanomas that arise in the setting of blue nevi, also known as "malignant blue nevus" or melanoma ex blue nevus (MBN), share a similar histopathological and mutational profile with uveal melanoma. Most uveal melanomas show characteristic GNA11 or GNAQ mutations; additional BAP1 mutation or loss is associated with the highest risk of metastasis and worst prognosis. However, the significance of BAP1 loss in melanomas ex blue nevus remains unclear. We present a case of MBN arising from the scalp of a 21-year-old woman. The diagnosis was established on histopathological findings demonstrating a markedly atypical melanocytic proliferation with increased mitotic activity, necrosis, and a focus of angiolymphatic invasion. Immunohistochemical analysis demonstrated the absence of BAP1 nuclear expression within tumor cells. Next generation sequencing detected GNA11 Q209L mutation and BAP1 loss (chromosome 3p region loss), supporting the diagnosis. We reviewed another 21 MBN cases with reported BAP1 status from the literature. MBN with BAP1 loss presented at a younger average age (41 vs. 61 years), demonstrated larger average lesion thickness (9.0 vs. 7.3 mm), and had a higher rate of metastasis (50% vs. 33%) compared with BAP1-retained MBN. BAP1 expression studies may assist in the diagnosis and management of MBN, but further research is needed.

ALK Rearrangements Are Infrequent in Cellular Blue Nevus and Deep Penetrating Nevus.

Recent studies have identified kinase fusions in Spitzoid melanocytic neoplasms, and approximately 10% of Spitzoid neoplasms harbor anaplastic lymphoma kinase (ALK) rearrangements and corresponding ALK immunoreactivity. Deep penetrating nevi (DPN), a subset of melanocytic neoplasms, have histologic and immunohistochemical overlap that have historically supported classification of DPN with blue/cellular blue nevi (CBN). However, HRAS mutations have rarely been detected in DPN, thereby also linking them to Spitz nevi. The purpose of this study was to see if DPN or CBN possess ALK rearrangements, thereby providing more evidence that these melanocytic lesions may be pathogenetically related to Spitzoid neoplasms. Using ALK immunohistochemistry as a surrogate for ALK rearrangement, the authors examined 26 DPN, 30 CBN, and 4 conventional blue nevi. ALK immunoreactive cases underwent fluorescent in situ hybridization to investigate for the presence of ALK gene rearrangement. Patchy and focal ALK immunostaining was found in only 1 case of DPN (1/26, 3.8%). Seven cases of CBN (7/30; 23%) showed ALK immunostaining (6 focal/patchy, 1 strong and diffuse). Fluorescent in situ hybridization using ALK break-apart probes showed various degrees of gain of 2p23 and rare ALK break-apart signals. Four CBN showed ALK rearrangement in 2%-4% of cells. Two cases of CBN showed gain of 2p23 in 10%-20% of cells. In our study, ALK rearrangements are uncommon in both CBN and DPN, making ALK an unlikely driver in tumorigenesis and classification of these melanocytic variants. However, our study did identify ALK molecular changes and immunohistochemical staining patterns that have not been previously described in CBN or DPN.

Blue nevus with satellitosis: case report and literature review.

Blue nevus is a benign melanocytic lesion, typically asymptomatic and of unknown etiology. Many histological subtypes are recognized, the most commons being: common blue nevus, cellular blue nevus, and combined blue nevus. New rare variants have been described in the literature, with emphasis on eruptive blue nevus, plaque, agminate, linear, with satellitosis, disseminated, familial and targetoid. The diagnosis of blue nevus usually presents no difficulties, however, the presence of structures such as irregular edges or satellitosis, are highly suggestive of malignancy, and the differential diagnosis with malignant blue nevus and melanoma with peripheral spread should be considered. We report a case of blue nevus with satellitosis in a 15-year-old female patient.

Atypical cellular blue nevus or malignant blue nevus?

Blue nevus is a benign melanocytic lesion whose most frequent variants are dendritic (common) blue nevus and cellular blue nevus. Atypical cellular blue nevus presents an intermediate histopathology between the typical and a rare variant of malignant blue nevus/melanoma arising in a cellular blue nevus. An 8-year-old child presented a pigmented lesion in the buttock since birth, but with progressive growth in the last two years. After surgical excision, histopathological examination revealed atypical cellular blue nevus. Presence of mitoses, ulceration, infiltration, cytological atypia or necrosis may occur in atypical cellular blue nevus, making it difficult to differentiate it from melanoma. The growth of blue nevus is unusual and considered of high-risk for malignancy, being an indicator for complete resection and periodic follow-up of these patients.

Atypical cellular blue nevus or malignant blue nevus?

Abstract: Blue nevus is a benign melanocytic lesion whose most frequent variants are dendritic (common) blue nevus and cellular blue nevus. Atypical cellular blue nevus presents an intermediate histopathology between the typical and a rare variant of malignant blue nevus/melanoma arising in a cellular blue nevus. An 8-year-old child presented a pigmented lesion in the buttock since birth, but with progressive growth in the last two years. After surgical excision, histopathological examination revealed atypical cellular blue nevus. Presence of mitoses, ulceration, infiltration, cytological atypia or necrosis may occur in atypical cellular blue nevus, making it difficult to differentiate it from melanoma. The growth of blue nevus is unusual and considered of high-risk for malignancy, being an indicator for complete resection and periodic follow-up of these patients.

Blue nevus with satellitosis: case report and literature review

Abstract: Blue nevus is a benign melanocytic lesion, typically asymptomatic and of unknown etiology. Many histological subtypes are recognized, the most commons being: common blue nevus, cellular blue nevus, and combined blue nevus. New rare variants have been described in the literature, with emphasis on eruptive blue nevus, plaque, agminate, linear, with satellitosis, disseminated, familial and targetoid. The diagnosis of blue nevus usually presents no difficulties, however, the presence of structures such as irregular edges or satellitosis, are highly suggestive of malignancy, and the differential diagnosis with malignant blue nevus and melanoma with peripheral spread should be considered. We report a case of blue nevus with satellitosis in a 15-year-old female patient.

Agminated blue nevus - Case report.

Blue nevi are benign melanocytic lesions located in the deeper reticular dermis, consequence of failure of melanocytic migration into the dermal-epidermal junction from the neural crest. Lesions are usually asymptomatic and solitary, but may present in a multiple or agminated (grouped) pattern. The agminated subtype is formed when bluish-pigmented lesions cluster together in a well-defined area. Lesions can be flat or raised. We report the case of a patient who presented multiple bluish macules (1-3 mm in diameter) grouped on the left upper back. Dermoscopy and anatomic pathological examination were consistent with blue nevus.

Agminated blue nevus - Case report

Abstract: Blue nevi are benign melanocytic lesions located in the deeper reticular dermis, consequence of failure of melanocytic migration into the dermal-epidermal junction from the neural crest. Lesions are usually asymptomatic and solitary, but may present in a multiple or agminated (grouped) pattern. The agminated subtype is formed when bluish-pigmented lesions cluster together in a well-defined area. Lesions can be flat or raised. We report the case of a patient who presented multiple bluish macules (1-3 mm in diameter) grouped on the left upper back. Dermoscopy and anatomic pathological examination were consistent with blue nevus.

Melanoma associated with congenital intermediate common blue nevus of the scalp - Case report.

Melanomas can arise either de novo (70%) or from pre-existing melanocytic lesions (30%). Of the latter, most cases arise at the dermoepidermal junction from small congenital or acquired non-blue nevi while only a few arise from blue nevi, notably the cellular subtype and less commonly the common (dendritic) type. Melanomas that arise from blue nevi usually occur on the scalp with greater frequency, as in the case described. Although previous studies have discussed melanoma arising from giant congenital blue nevi, few have discussed those arising from intermediate blue nevi. We present a case of a 52-yearold man with melanoma on the scalp evolving from an intermediate congenital common blue nevus.

Melanoma associated with congenital intermediate common blue nevus of the scalp - Case report

Abstract: Melanomas can arise either de novo (70%) or from pre-existing melanocytic lesions (30%). Of the latter, most cases arise at the dermoepidermal junction from small congenital or acquired non-blue nevi while only a few arise from blue nevi, notably the cellular subtype and less commonly the common (dendritic) type. Melanomas that arise from blue nevi usually occur on the scalp with greater frequency, as in the case described. Although previous studies have discussed melanoma arising from giant congenital blue nevi, few have discussed those arising from intermediate blue nevi. We present a case of a 52-yearold man with melanoma on the scalp evolving from an intermediate congenital common blue nevus.

Melanoma tipo animal / Animal-type melanoma

El melanoma tipo animal o equino, es una variante infrecuente de melanoma con pronóstico incierto. Su nombre se debe a las similitudes histológicas con una neoplasia melanocítica presente en caballos tordillos ancianos. Clínicamente se presenta como una lesión nodular o una placa, con pigmentación intensa, pardo-azulada o negra. Histológicamente presenta principalmente una localización dérmica, observándose una proliferación profunda de células elongadas o redondeadas con moderada atipía ybaja tasa mitótica. Presentamos el caso de un paciente de sexo masculino de 31 años de edad, HIV +, con diagnóstico de melanoma tipo animal...

Argyria mimicking a blue nevis: dermoscopy features.

Argyria is a rare disease caused by prolonged skin contact with silver. Localized cases have been described regarding the use of topical medications, and trauma with objects containing this metal such as acupuncture needles and jewelry. Clinically, a macule or a patch, round or oval, appears in the infected area, with a characteristic bluey-gray color. To our knowledge this is the first time that this clinical condition has been described through the use of dermoscopy.