Immunohistochemical Markers in the Differential Diagnosis of Melanoma and Nevus in Humans

SUMMARY: Immunohistochemistry allows in situ detection of cell and extracellular components through specific antibodies. The objective was to compare the immunohistochemical expression patterns of the S-100, HMB-45 and MART-1 proteins for differential diagnosis of malignant melanoma and melanocytic nevus in human skin biopsies. Thirty-nine biopsies of human tissue were used. They were divided into two groups: 19 in malignant melanoma and 20 in melanocytic nevi. Next, the samples were fixed with paraformaldehyde and processed following the protocol for inclusion. Then, immunohistochemical staining was performed. Finally, the histological and qualitative analysis of the samples was carried out. S-100, HMB-45, and MART-1 markers showed positive immunoreaction in melanoma biopsies. HMB-45 marker was generally present with weaker expression than S-100 and MART-1 in melanocytic nevus biopsies. No expression pattern was observed which specifically associates one or more markers with some types of histopathological diagnosis. Immunohistochemistry is fundamental in differential diagnosis of melanomas and melanocytic nevi. However, there is no antibody or set of antibodies which allows unequivocal diagnosis between melanoma and nevus. It is therefore necessary to analyze with care the expression pattern and location of the lesion using standard morphological characteristics.

RESUMEN: La inmunohistoquímica permite la detección in situ de componentes celulares y extracelulares a través de anticuerpos específicos. El objetivo de nuestro estudio fue comparar los patrones de expresión inmunohistoquímica de las proteínas S-100, HMB-45 y MART-1 para el diagnóstico diferencial de melanoma maligno y nevo melanocítico en biopsias de piel humana. Se utilizaron treinta y nueve biopsias de tejido humano, las que fueron divididas en dos grupos: 19 en melanoma maligno y 20 en nevos melanocíticos. A continuación, las muestras se fijaron con paraformaldehído y se procesaron siguiendo el protocolo convencional para su inclusión. Luego, se realizó la tinción inmunohistoquímica. Finalmente, se realizó el análisis histológico y cualitativo de las muestras. Los marcadores S-100, HMB- 45 y MART-1 mostraron inmunorreacción positiva en biopsias de melanoma. El marcador HMB-45 estuvo generalmente presente con una expresión más débil que S-100 y MART-1 en biopsias de nevo melanocítico. No se observó ningún patrón de expresión que asocie específicamente uno o más marcadores con algunos tipos de diagnóstico histopatológico. La inmunohistoquímica es fundamental en el diagnóstico diferencial de melanomas y nevos melanocíticos. Sin embargo, no existe ningún anticuerpo o panel de anticuerpos que permita un diagnóstico inequívoco entre el melanoma y el nevo. Por tanto, es necesario analizar con cuidado el patrón de expresión y la localización de la lesión utilizando características morfológicas estándar.

Nevus lipomatosus cutaneous superficialis

Abstract: Nevus lipomatosus cutaneous superficialis is a rare benign hamartomatous skin tumor characterized by dermal deposition of mature adipose tissue. Two clinical forms have been described (classical and solitary types). We describe a case of nevus lipomatosus cutaneous superficialis with a 13-year history of growth in a young woman who had a solitary skin-colored tumoral mass on the right buttock. Histopathological findings were typical and confirmed the diagnosis. In this case, the lesion was a skin-colored isolated mass, as described in the solitary type, but its localization and age of appearance were compatible with the classical type. The combination of simultaneous clinical findings of both types had not been published before.

Multiple vulvar dilated pores in a postmenopausal woman

Abstract: Winer's dilated pore is an infrequent appendageal tumor characterized by a giant comedone on the face, neck, and upper trunk in adults. We report a 57-year-old woman who developed multiple asymptomatic black papules on both labia majora. Histopathology showed grouped dilated follicles lined by keratinizing squamous epithelium in the superficial dermis. The superficial lining epithelium and interfollicular epidermis were atrophic, while the deep epithelium showed mild proliferation and melanin pigmentation with a few short projections extending into the surrounding dermis. We diagnosed multiple Winer's dilated pores based on late-onset lesions and pathological features. This patient may represent the first case of multiple vulvar Winer's dilated pores. We suggest that electrocautery may be effective for treating this type of superficial entity.

Histopathological diagnosis of small melanocytic lesions suspicious for malignant melanoma

Abstract The concern about malignant skin neoplasms leads to the excision of smaller lesions. This study on small melanocytic lesions aims to evaluate the range of possible histopathological diagnoses, describe histopathological aspects, and assess the usefulness of serial histological sections. We performed a cross-sectional descriptive histopathological study examining 76 pigmented skin lesions up to 6 mm in diameter. Histopathological diagnoses included atypical melanocytic nevi (n=38), common melanocytic nevi (n=18), atypical lentiginous melanocytic hyperplasia with architectural features of atypical melanocytic nevi (n=7), lentigo simplex (n=2), and malignant melanoma (n=1). Ten cases were non-diagnostic. Cytological atypia was not an exclusive finding of atypical lesions. Examination of serial sections did not change histopathological impression. Early detection of malignant melanoma is important, but clinical and dermoscopy exams may be leading to the resection of a great number of benign lesions. Strict attention to histopathological criteria results in a large number of non-diagnostic cases.

Proliferative nodule in melanocytic nevi mimicking deep penetrating nevus

Abstract: Proliferative nodules can occasionally arise on congenital and acquired melanocytic nevi. At first sight their clinical and pathologic features cause alert to both dermatologist and dermatopathologist. However, proliferative nodules are typically benign, regression is common and there is minimum risk of malignization. We present a new case of proliferative nodule in melanocytic nevi with features of deep penetrating nevus.

Wooly hair nevus

Abstract Woolly hair nevus is a rare condition characterized by a structural anomaly of the hair, restricted to certain areas of the scalp. The hair becomes coiled and slightly hypopigmented. The term woolly hair refers to changes that affect all the scalp and has a hereditary character. We present a case of woolly hair nevus, that developed at the age of 2 years, associated with dental diastema and verrucous epidermal nevus.

Porokeratotic eccrine and hair follicle nevus: a report of two cases and review of the literature

Abstract: Porokeratotic eccrine and hair follicle nevus is a very rare non-hereditary disorder of keratinization with eccrine and hair follicle involvement with only 9 cases described in the literature. In 2009 the term porokeratotic anexial ostial nevus was proposed to comprehend porokeratotic eccrine and hair follicle nevus and a related and more common process without follicular involvement: porokeratotic eccrine ostial and dermal duct nevus Recent findings suggest that both entities may be produced by a mutation in GJB2 gene, which is associated to KID syndrome. Herein we report 2 cases of porokeratotic eccrine and hair follicle nevus and review the existing cases in the Spanish and English literature.

Elastoma: clinical and histopathological aspects of a rare disease

Abstract Elastoma is a connective tissue nevus characterized by changes in elastic fibers. It can be congenital or acquired, and is usually diagnosed before puberty. Associated with osteopoikilosis, it is known as Buschke-Ollendorff syndrome. Histopathology with specific staining for elastic fibers is critical for a diagnostic conclusion. This report describes the case of a 7-year-old male patient with lesions diagnosed as elastoma, with absence of bone changes in the radiological imaging. This study aims to report the clinical presentation and histological examination of such unusual disease.

Nevus lipomatosus cutaneous superficialis

Abstract We report a case of nevus lipomatosus cutaneous superficialis of Hoffman-Zurhelle (NCLS), with multiple lesions, in a ten-year-old child. The NLCS is considered rare. The classical clinical presentation is characterized by multiple skin-colored or yellowish papules and nodules, which can have a linear distribution. Histologically, it is characterized by the presence of mature ectopic adipocytes in the dermis. The main therapeutic option is surgical excision. The classical Nevus lipomatosus cutaneous superficialis is reported in this case.

Three different clinical faces of the same histopathological entity: hair follicle nevus, trichofolliculoma and accessory tragus

AbstractBACKGROUND:Hair follicle nevus is a rare, congenital hamartoma with follicular differentiation characterized histologically by numerous, tiny, mature hair follicles. Trichofolliculoma, the histopathological features of which are quite similar to those of hair follicle nevus, is also a hamartoma that differs from hair follicle. Accessory tragus is a relatively common, benign congenital abnormality of the external ear with an incidence rate of 1 to 10 per 1,000 live births.OBJECTIVE:This study seeks to assess the discriminatory value of currently available, histological criteria in the differential diagnosis of hair follicle nevus, accessory tragi and trichofolliculoma.METHODS:Twenty-one patients comprising 9 cases of hair follicle nevus, 8 accessory tragi patients and 4 trichofolliculoma cases, were recruited to perform the study.RESULTS:There were 10 males and 11 females in the study group. No significant difference was observed between the three study groups in terms of age, gender or histopathological parameters such as density of hair follicles, subcutaneous fat score and presence of connective tissue framework. Cartilaginous component was seen in 8 cases that were diagnosed as accessory tragi, while central cyst and radiating hair follicles were seen in 4 cases which were diagnosed as trichofolliculoma.CONCLUSION:The results of our study showed that diagnostic discrimination of these diseases could be made only with the clinicopathologic correlation because of their clinical and histopathological similarities.

Vascular structures in dermoscopy

AbstractDermoscopy is an aiding method in the visualization of the epidermis and dermis. It is usually used to diagnose melanocytic lesions. In recent years, dermoscopy has increasingly been used to diagnose non-melanocytic lesions. Certain vascular structures, their patterns of arrangement and additional criteria may demonstrate lesion-specific characteristics. In this review, vascular structures and their arrangements are discussed separately in the light of conflicting views and an overview of recent literature.

Cerebriform sebaceous nevus: a rare presentation

Abstract A 13-year-old boy presented congenital, raised, yellowish colored plaques with fibroelastic consistency, which were velvety in appearance, alopecic, with clearly defined limits and sulci or well-marked meandering invaginations, a cerebriform appearance on the upper part of the right ear, accompanied by alopecia in the temporomandibular region-parietal. The lesion was asymptomatic. Histopathologic examination revealed acanthosis, hyperkeratosis, papillomatosis and follicular plugging in the epidermis. The upper dermis showed underdeveloped hair follicles with sebaceous glands, consistent with sebaceous nevus. There were no skeletal, cardiological, ophthalmological or neuropsychomotor changes; nor were there any records of relevant pathologies in the family history. The patient complained of his appearance, experiencing aesthetic and social issues. Following a diagnosis of cerebriform nevus sebaceous, complete excision was performed with excellent aesthetic results.

Nevus sebáceo cerebriforme: uma rara apresentação

A 13-year-old boy presented congenital, raised, yellowish colored plaques with fibroelastic consistency, which were velvety in appearance, alopecic, with clearly defined limits and sulci or well-marked meandering invaginations, a cerebriform appearance on the upper part of the right ear, accompanied by alopecia in the temporomandibular region-parietal. The lesion was asymptomatic. Histopathologic examination revealed acanthosis, hyperkeratosis, papillomatosis and follicular plugging in the epidermis. The upper dermis showed underdeveloped hair follicles with sebaceous glands, consistent with sebaceous nevus. There were no skeletal, cardiological, ophthalmological or neuropsychomotor changes; nor were there any records of relevant pathologies in the family history. The patient complained of his appearance, experiencing aesthetic and social issues. Following a diagnosis of cerebriform nevus sebaceous, complete excision was performed with excellent aesthetic results.

Opções terapêuticas no manejo do nevus congênito gigante, experiência do Serviço de Cirurgia Plástica e Reaparadora HC-UFPR / Therapeutic options in the management of giant congenital nevus: Experience of the Plastic and Reconstructing Service at Hospital de Clínicas, Federal University of Paraná

INTRODUÇÃO: O nevus congênito gigante (NCG) possui diversas modalidades de tratamento. A abordagem cirúrgica inclui a ressecção parcial seriada ou excisão total. Objetivo: Demonstrar as principais modalidades terapêuticas utilizadas para o tratamento do NCG e avaliar a incidência da localização, idade e tamanho destas lesões no Serviço de Cirurgia Plástica e Reparadora do Hospital de Clínicas da Universidade Federal do Paraná. MÉTODOS: Estudo retrospectivo dos pacientes submetidos a tratamento cirúrgico do NCG no período de janeiro de 2004 a janeiro de 2010. Foram coletados dados como: idade, gênero, tratamento realizado, número de cirurgias realizadas, evolução e complicações. RESULTADOS: Foram avaliados 11 pacientes, sendo 8 mulheres e 3 homens. A média de idade foi de 12,4 anos (3 a 25 anos). O subtipo mais encontrado foi o nevus melanocítico intradérmico correspondendo a 90,9% dos casos e 9,1% com nevus melanocítico composto. Não foram identificados casos de melanoma. A localização mais comum foi a região da cabeça e pescoço. O diâmetro médio das lesões foi de 9,1 cm.As técnicas utilizadas para reconstrução foram: sutura primária, retalhos locais, enxerto de pele e uso de expansores. No seguimento, 63,6% dos pacientes apresentavam ainda nevus residual, 27,3% apresentaram ressecção completa e 9,1% perderam seguimento. CONCLUSÃO: Foi observada maior incidência de NCG na faixa etária de 3 a 25 anos, sendo a localização mais comum na face e com tamanho médio de 9,1cm. O principal tratamento instituído para os pacientes com NCG foi a ressecção parcelada, com bons resultados.

INTRODUCTION: Several modalities are available for the treatment of giant congenital nevus (GCN). The surgical approach includes partial serial resection or total excision. Objective: To demonstrate the main therapeutic modalities in the treatment of GCN and to assess the incidence of location, age, and size of this lesion at the Plastic and Reconstructive Surgery Service of the Hospital de Clínicas, Federal University of Paraná. METHODS: This retrospective study included patients who had undergone surgical treatment for GCN between January 2004 and January 2010. We collected data such as age, sex, treatment performed, number of surgeries carried out, evolution, and complications. RESULTS: We evaluated 11 patients (8 female and 3 male). The average age was 12.4 years (range, 3-25 years). The GCN subtype most commonly found was intradermal melanocytic nevus, which accounted for 90.9% of cases, with melanocytic nevus accounting for the remaining 9.1%. No cases of melanoma were identified. The most common location was the head and neck. The average diameter of the lesions was 9.1 cm. The techniques used for the reconstruction included primary suture, local flaps, skin graft, and the use of expanders. In the follow-up period, 63.6% of the patients still presented a residual nevus, 27.3% underwent complete resection, and 9.1% were not monitored. CONCLUSION: A higher incidence of GCN was observed in patients aged 3-25 years. The most common location was the face, and the average size was 9.1 cm. The main treatment of patients with GCN was splitting resection, which resulted in satisfactory outcomes.