Neoplasias melanocíticas spitzoides: estudio clínico-histopatológico de 62 lesiones en un hospital universitario chileno / Spitzoid melanocytic neoplasms: clinical-histopathological study of 62 lesions in a Chilean university hospital

INTRODUCCIÓN: Las neoplasias spitzoides son tumores melanocíticos con un espectro biológico variable, que constituyen un desafío diagnóstico. Los estudios en población latinoamericana son muy escasos, no contando con series chilenas. OBJETIVO: Caracterizar clínica e histopatológicamente a los pacientes con neoplasias spitzoides en el Hospital Clínico de la Universidad de Chile. METODOLOGÍA: Estudio retrospectivo, basado en revisión de fichas clínicas y biopsias de pacientes con diagnóstico confirmado de nevo de Spitz (NS), tumor de Spitz atípico y melanoma spitzoide, entre 1995-2018. Se analizó: edad, sexo, características clínicas e histopatológicas. RESULTADOS: Se estudiaron 62 neoplasias spitzoides. 39 mujeres (62,9%). Edad promedio de 18,9 (+14,3) años. Localización de lesiones: 8 (12,9%) cabeza, 6 (9,7%) tronco, 17 (27,4%) extremidades superiores y 22 (35,5%) extremidades inferiores; en 9 (14,5%) no se registró. Tamaño promedio 5,5 mm. Respecto al diagnóstico clínico: 21 (33,9%) nevo melanocítico, 16 (25,8%) nevo atípico, 12 (19,4%) NS, 7 (11,3%) lesiones vasculares, 3 (4,8%) melanoma y 3 (4,8%) otro. En cuanto al diagnóstico histopatológico: NS clásico 38 (61,3%), Nevo de Reed 9 (14,5%), NS desmoplásico 2 (3,2%), NS atípico 8 (12,9%) y melanoma spitzoide 5 (8,1%). CONCLUSIÓN: El presente estudio constituye la primera serie chilena de neoplasias spitzoides, según la literatura revisada. Destaca el mayor número de lesiones en mujeres y en extremidades, lo que ya había sido informado en otras series similares. Considerando la dificultad en el diagnóstico clínico preoperatorio, destaca un número mayor de sospecha de neoplasias spitzoides comparado a otros estudios.

INTRODUCTION: Spitzoid neoplasms are melanocytic tumors with a variable biological spectrum, which are a diagnostic challenge. There are few studies in Latin American population, not finding chilean series. OBJECTIVE: Clinically and histopathologically characterize patients with spitzoid neoplasms in the Hospital Clínico Universidad de Chile. METHODOLOGY: Retrospective study, based on re-view of clinical records and biopsies of patients with confirmed diagnosis of Spitz nevus (SN), atypical Spitz tumors and spitzoid melanoma (SM), between 1995-2018. It is analyzed: age, sex, clinical and histopathological characteristics. RESULTS: 62 spitzoid neoplasms were studied. 39 women (62.9%). Average age of 18.9 (+14.3) years. Location of injuries: 8 (12.9%) head, 6 (9.7%) trunk, 17 (27.4%) upper extremities and 22 (35.5%) lower extremities; in 9 (14.5%) it is not identified. Average size 5.5 mm. Clinical diagnosis: 21 (33.9%) melanocytic nevus, 16 (25.8%) atypical nevus, 12 (19.4%) NS, 7 (11.3%) vascular lesions, 3 (4.8%) melanoma and 3 (4.8%) other. Histopathological diagnosis: classic NS 38 (61.3%), Reed Nevus 9 (14.5%), desmoplastic SN 2 (3.2%), atypical SN 8 (12.9%) and SM 5 (8.1%). CONCLUSION: The present study appears in the first chilean series of spitzoid neoplasms, according to the literature reviewed. It highlights the greatest number of injuries in women and in the extremities, which had already been reported in other similar series. In the preoperative clinical diagnosis, a greater number of suspicion of spitzoid neoplasms stands out compared to other studies.

Immunoexpression of BAP1, ROS1, and ALK in Spitzoid Melanocytic Tumors.

BACKGROUND: Spitzoid tumors are a heterogeneous group of melanocytic neoplasms that frequently imposes diagnostic difficulties. Lately, several advances in molecular biology afforded significant discoveries on the pathogenesis of these tumors. BAP1 (BRCA-1 associated protein-1) inactivation and anomalous expression of kinase translocation-related proteins are among the main criteria launched by new classification proposals. Our aim was to systematically assess the immunoexpression of BAP1, ROS1 (receptor tyrosine kinase c-Ros oncogene 1), and ALK (anaplastic lymphoma receptor tyrosine kinase) proteins in an unpublished series of spitzoid tumors. METHODS: Retrospective study based on 47 formalin-fixed paraffin-embedded tissue samples from 3 different institutions. BAP1, ROS1, and ALK immunostains were performed in all cases. We included 27 Spitz tumors without significant abnormality, 15 atypical spitzoid tumors, and 5 spitzoid melanomas. RESULTS: We observed loss of BAP1 nuclear immunolabeling in 4.3% of evaluable cases (2/46), both of them atypical spitzoid tumors. The proportional frequency of BAP1-inactivated cases among atypical spitzoid tumors was 14.2% (2/14). No immunoexpression of ROS1 or ALK was found. CONCLUSIONS: Our study revealed 2 additional BAP1-inactived cases and described its respective frequency. The absence of anomalous expression of translocation-related proteins ALK and ROS1 in this series, composed predominantly of low-grade/low-risk tumors, indicates that translocated spitzoid lesions may not be as prevalent as initially suggested, at least in some populations. Furthermore, our findings encourage additional investigation on unequal occurrence of such immunomarkers among different diagnostic categories of spitzoid neoplasms.

Clinical Follow-up of Atypical Spitzoid Tumors Analyzed by Fluorescence In Situ Hybridization.

Many neoplasms with spitzoid features remain enigmatic, especially those with intermediate grade features or "atypical spitzoid tumors" (ASTs). Fluorescence in situ hybridization (FISH) has emerged as a complementary technique to conventional microscopy, with certain chromosomal patterns conveying diagnostic information. In this study, we examined 36 ASTs analyzed by FISH for specific abnormalities in chromosomes 6, 9, and 11. Aberrations were detected in 11 cases, 7 of which met FISH criteria for spitzoid melanoma. These had homozygous deletion of 9p21, partial deletion of 11q13, gain of 6p25, and gain of 11q13. All 3 patients with positive sentinel lymph nodes, including one with progression beyond the sentinel lymph node, had homozygous deletion of chromosome 9p21, but there were no deaths in an average of 28 months of follow-up of these cases. Other aberrations in the chromosomal pattern of ASTs were heterozygous deletion of 9p21, partial deletion of 6p23, and tetraploidy. We found that ASTs, including those eventually diagnosed as spitzoid melanoma, had a more indolent course in our cohort than conventional malignant melanoma. Moreover, the addition of FISH results led to a more definitive diagnosis in 7 cases, 4 of which had abnormalities on FISH consistent with spitzoid melanoma.

Spitz nevus and Reed nevus.

Spitz and Reed nevi, also called spindle and/or epithelioid cell nevi, are a special group of melanocytic lesions due to their peculiar clinical, dermoscopic and histopathological features. The study of these nevi is of great interest because both their nomenclature and classification are still a matter of discussion. Most importantly, the difficulty to differentiate them from melanoma can lead to inadequate therapies. In this context, dermoscopy, a link between clinical and anatomopathological examinations, appears as a helpful diagnostic tool whose accuracy can reach 93%. "Borderline" lesions are still a great challenge and object of research, including molecular studies. The present study explores the relevant characteristics of these nevi, with emphasis on dermoscopic findings, aiming at understanding their natural history, as well as discussing treatment and patient follow-up.

Spitz nevus and Reed nevus / Nevo de Spitz e nevo de Reed

Spitz and Reed nevi, also called spindle and/or epithelioid cell nevi, are a special group of melanocytic lesions due to their peculiar clinical, dermoscopic and histopathological features. The study of these nevi is of great interest because both their nomenclature and classification are still a matter of discussion. Most importantly, the difficulty to differentiate them from melanoma can lead to inadequate therapies. In this context, dermoscopy, a link between clinical and anatomopathological examinations, appears as a helpful diagnostic tool whose accuracy can reach 93%. "Borderline" lesions are still a great challenge and object of research, including molecular studies. The present study explores the relevant characteristics of these nevi, with emphasis on dermoscopic findings, aiming at understanding their natural history, as well as discussing treatment and patient follow-up.

Os nevos de Spitz e de Reed, ou também chamados nevos de células fusiformes e/ou epitelióides, formam um grupo especial de lesões melanocíticas, por suas características peculiares, tanto clínicas como dermatoscópicas e histopatológicas. Torna-se grande o interesse no estudo desses nevos, pois tanto a nomenclatura como a classificação ainda são motivos de debate e, sobretudo, a dificuldade de diferenciação com o melanoma pode gerar condutas terapêuticas inadequadas. Neste contexto, surge a dermatoscopia, elo entre o exame clínico e o anatomopatológico, como método diagnóstico auxiliar importante cuja acurácia pode chegar a 93%. A grande dificuldade ainda são as lesões "borderline", motivo de pesquisas, incluindo estudos moleculares. O presente estudo aborda os aspectos relevantes das características destes nevos, com ênfase nos achados dermatoscópicos, buscando o entendimento da sua história natural, além da discussão quanto ao tratamento e seguimento dos pacientes.

Dermatoscopy of an angiomatoid spitz nevus.

To date, only 12 cases of angiomatoid Spitz nevus have been characterized in the literature. We present the first case of angiomatoid Spitz nevus in which dermatoscopic findings are described.

Spitzoid melanoma: dermoscopic report and diagnostic discussion.

We present a case of a 16-year-old young man who came for a dermatologic appointment due to acne. He presented a pigmented asymptomatic lesion on the back of his right thigh. Dermoscopic examination revealed uncommon aspects, highly suspect of nodular melanoma, in particular a blue-whitish veil, striae and asymmetric globules. The lesion was promptly removed and the material referred for histopathologic examination. Microscopic findings showed an atypical spitzoid tumor, compatible with spitzoid melanoma. In this report, the importance of dermoscopy as an auxiliary method in the early diagnosis of cutaneous melanomas is emphasized. Its daily use by the dermatologist is an important tool in the decision-making process in cases of urgent removal of suspect lesions.

Critérios histopatológicos para diagnóstico de melanoma maligno cutâneo: análise comparativa de sua freqüência em lesões benignas e melanomas de pequena espessura (< 2 mm) / Histopathological criteria for cutaneous malignant melanoma: comparative analysis between benign and thin malignant lesions (< 2 mm)

INTRODUÇÃO: A histopatologia convencional continua sendo o padrão-ouro no diagnóstico dos melanomas cutâneos, apesar do progresso da imuno-histoquímica e da biologia molecular. Os critérios microscópicos existentes para esse diagnóstico são numerosos, porém nenhum deles é específico para se afirmar que uma determinada lesão é maligna quando ele está presente, ou é benigna na sua ausência. Alguns critérios têm uma relevância maior para o diagnóstico em relação a outros. OBJETIVO: Este estudo propõe uma análise daqueles critérios considerados mais importantes, comparando sua presença em lesões melanocíticas benignas e melanomas. MATERIAL E MÉTODOS: Foram estudadas 33 lesões melanocíticas benignas (nevo de Spitz: 13; nevo de Reed: 6; nevo displásico: 6; nevo congênito: 3; nevo adquirido: 3; nevo combinado: 1; nevo recorrente: 1), bem como 101 casos de melanomas extensivo/superficiais: 25 intra-epidérmicos e 76 invasivos de pequena espessura (< 2 mm). RESULTADOS: Alguns critérios mostraram alta freqüência em lesões benignas, apresentando pouca especificidade, enquanto outros tiveram menor positividade nas benignas, e alta freqüência nas malignas, mostrando sua maior especificidade e importância no diagnóstico dos melanomas. CONCLUSÃO: Os cinco critérios que mostraram diferenças estatisticamente significativas na comparação com as lesões benignas foram (em ordem decrescente de freqüência): 1. proliferação linear de células isoladas na camada basal; 2. início e fim da lesão com células isoladas; 3. melanócitos na camada granular; 4. disseminação pagetóide extensa; 5. nucléolos grandes, irregulares ou múltiplos. Os melanomas de pequena espessura não apresentam parte dos critérios considerados mais importantes, como falta de maturação, necrose e mitoses profundas.

INTRODUCTION: Conventional histopathology has been considered as the gold standard in the diagnosis of cutaneous malignant melanoma, despite the progress of molecular biology and immunohistochemistry. There are many microscopic criteria for diagnosis of melanoma, however there is not a single one that can be useful to define malignancy. AIM: Our purpose is to analyse the criteria considered more important to the diagnosis of melanoma, comparing their presence in benign melanocytic lesions and melanomas. MATERIAL AND METHODS: We studied 33 benign melanocytic lesions (Spitz nevi, 13; Reed nevi, 6; dysplastic nevi, 6; congenital nevi, 3; acquired nevi, 3; combined nevus, 1; recurrent nevus, 1) and 101 extensive/superficial melanomas (25 in situ and 76 invasive up to 2 mm thickness). RESULTS: Some criteria showed high frequency in benign lesions, showing low-specificity, while others had low-positivity in the benign and high-frequency in malignant lesions, consequently high-specificity and greater importance in the melanoma diagnosis. CONCLUSION: The five criteria that presented statistically significant difference after comparison with benign lesions were: 1. linear proliferation of a single layer cells in basal layer; 2. single cells at periphery; 3. cells in the granular layer; 4. extensive pagetoid array; and 5. large, irregular and/or multiple nucleoli . Thin melanomas usually do not show many of important criteria, like lack of cell maturation, necrosis and deep mitoses.

Spitz Nevus: a Study of Clinical and Morphological Variables

Spitz nevus is an uncommon benign melanocytic neoplasia that shares many clinical and histological characteristics typical ofmelanoma, making difficult the differential diagnosis between these neoplasias. Objective: To evaluate clinical andanatomopathological data on Spitz nevus (and Reed nevus – a variant of Spitz nevus) contained in the casuistry of the archivesof the Center of Treatment and Research of A. C. Camargo Cancer Hospital, São Paulo, Brazil. Methods: A retrospective studyconsisting in analyzing the archives of the Department of Pathological Anatomy of Hospital of Cancer related to diagnosis ofSpitz nevus, youthful melanoma, Reed nevus and Spitzoid melanoma (used for comparison). The analyzed cases cover aninterval from 1982 to 2004. Clinical variables were obtained by analyzing patients’ history, and the histological analysis wasbased on anatomopathological criteria for Spitz and Reed nevus. Results: In a hundred patient histories, 69 cases were foundof Spitz nevus, all with history and/or slides archived in the hospital. Of these, 44 histological preparations had been analyzed.Globally median age of appearance of the lesion was of 20.33 years (varying from 2 to 53), with female predominance (68%),being injuries situated mainly in the inferior members (50%). The histological aspects found correspond to the ones referred inthe literature, being circumscribed, symmetrical, consisting of spindle and epithelioid cells, with a moderate degree of nuclearatipies, rare mitoses and Kamino corpuscles (29.5%). However, some cases presented characteristics like small circumscription,asymmetry, intense cellularity and pagetoid dissemination, potential causes of differential diagnosis errors between thisdisease and melanoma. Conclusion: Although dermatological examination can lead to a suspicion of a Spitz and...

Nevo de Spitz. Importancia de sus variedades clínicas / Spitz news. Importance of its clinical varieties

Se presentan seis pacientes de nevo de Spitz, cuatro en niños, uno en un adolescente y el sexto caso en un adulto joven. Cuatro pacientes presentan nevos deSpitz clínica e histológicamente típicos. Dos pacientes presentan nevos de Spitz clínicamente atípicos (AU)

Nevos melanocíticos benignos / Benign melanocytic nevi

Los nevos melanocíticos constituyen un motivo frecuente de consulta dermatológica. En el presente artículo, se revisan las principales características clínicas e histopatológicas de los nevos melanocíticos benignos, con especial énfasis en el nevo displásico. Se menciona la microscopía de superficie como método de ayuda en el diagnóstico diferencial de estas lesiones cutáneas, describiendo algunos patrones microscópicos característicos. Finalmente se presenta la experiencia de 6 años en lesiones melanocíticas biopsiadas en el Servicio de Dermatología y Enfermedades de Transmisión Sexual del Hospital Clínico Regional de Valdivia, y se propone un modelo de ficha clínica que consideramos de utilidad para futuros estudios

Nevo de Spitz hialinizante: relato de un caso y comentario de la utilidad de la inmunohistoquímica / Spitz hialinizing nevus: report of a case and comment of the immunohistochemistry utility

Se describe un caso de una variante histológica diferente de un nevo de células fusiformes y epitelioides, caracterizado por una hialinización extensa y prominente del estroma. La lesión consistía en una proliferación de células névicas fusiformes o epitelioides, diseminadas linealmente o en pequeños nidos y rodeadas por un estroma colágeno o hiali izado paucicelular abundante. Las tinciones inmunohistoquímicas mostraron positividad de las células fusiformes y epitelioides con proteína S-100 y vimentina, las tinciones para queratina, EMA, CEA, actina y desmina fueron todas negativas. Las reacciones histoquímicas Van Gieson y tricrómica demostraron la naturaleza colágena de la matriz intercelular hialinizada; las tinciones rojo congo, violeta cristal y azul al cian fueron todas negativas. La etiología y patogénesis de los depósitos hialinos intercelulares es desconocida, pero ellos representan probablemente un fenómeno regresivo en la detención o involución de las lesiones. El nevo de Spitz hialinizante debe ser incluido en el diagnóstico diferencial de lesiones cutáneas que exhiben un estroma hialinizado prominente y debe ser diferenciado de otras neoplasias dérmicas, particularmente metástasis cutáneas de tumores internos ocultos y de melanomas malignos

Nevo de células fusiformes y epitelioides (Spitz) en el adulto: presentación de 14 casos / Adult Spitz Nevus: a presentation of 14 cases

El Nevo de Spitz es una variante de nevo de células névicas, con especiales características clínicas e histológicas, que pueda simular...