Application of fluorescence in situ hybridization as a diagnostic tool in melanocytic lesions, using paraffin wax-embedded tissues and imprint-cytology specimens.

BACKGROUND: Accurate histopathological diagnosis of certain melanocytic skin lesions as benign or malignant can be notoriously difficult. Recently, four-colour fluorescence in situ hybridization (FISH) has emerged as an important tool for classifying these lesions. AIM: To evaluate the sensitivity and specificity of a melanoma FISH probe kit for accurate diagnosis of melanocytic tumours, and to validate its use with imprint-cytology specimens from the cut surface of tumours. METHODS: In total, 50 melanocytic skin lesions (31 malignant melanomas, 10 benign melanocytic naevi, and 9 histologically challenging benign melanocytic skin lesions) were evaluated. The samples comprise 47 tissue specimens embedded in paraffin wax, and three imprint-cytology specimens from the cut surface of melanomas. FISH was performed using four locus-specific identifier probes [Ras responsive element binding protein (RREB)1, myeloblastosis viral oncogene homologue (MYB), cyclin (CCN)D1 and centromere of chromosome (CEP)6], and results were compared with the clinical long-term follow-up and histopathological diagnosis data. RESULTS: The melanoma FISH probe distinguished between naevi and melanomas with a sensitivity of 100% and a specificity of 94.1%. The most sensitive criterion was a gain in 6p25 (RREB1), seen in 100% of cases, followed by CEP6-related MYB loss (48.1%), CCND1 gain (37%) and MYB gain (22.2%). More than three-quarters (77.8%) of melanomas were positive for two or more criteria. Positive FISH results were also obtained for the imprint-cytology specimens. CONCLUSIONS: FISH is a valuable diagnostic tool for differentiating between benign and malignant melanocytic lesions, providing a high degree of sensitivity and specificity. The probes displayed exceptional discriminative capacity in difficult or ambiguous lesions. To our knowledge, his is the first reported use of imprint-cytology specimens for FISH diagnosis.

[Approaches to the dermatopathologic diagnosis of figurate lesions]. / Aproximación al diagnóstico dermatopatológico de las lesiones figuradas.

Both clinical and pathologic findings must be considered when diagnosing figurate skin lesions, which are often seen in routine practice. Although a skin biopsy may sometimes be diagnostic, more often the information provided is nonspecific. In an attempt to offer an approach to diagnosing these dermatoses, we have classified annular lesions according to the presence of lymphocytic, neutrophilic-eosinophilic, or granulomatous infiltrates, and infiltrates containing plasma cells. Neoplastic annular lesions are included in a separate group. Lesions containing lymphocytic infiltrates include superficial and deep erythema annulare centrifugum and the differential diagnosis includes a large number of conditions. In the neutrophilic-eosinophilic class, we include annular psoriasis, vasculitis, linear immunoglobulin A dermatosis, eosinophilic dermatitis, erythema marginatum rheumatica, and annular erythema of infancy. Sarcoidosis and granuloma annulare are the prototypical annular lesions containing granulomas. Secondary syphilis is typical of lesions containing plasma cells. Mycosis fungoides is the principal skin tumor that may initially manifest with annular lesions.

[Primary cutaneous melanoma: prognostic factors not included in the classification of the American Joint Committee on Cancer]. / Factores pronósticos en el melanoma cutáneo primario no incluidos en la clasificación de la American Joint Committee on Cancer (AJCC).

Skin histopathology reports of melanoma routinely include important prognostic information used in the staging system of the American Joint Committee on Cancer (AJCC). This information, which influences disease management, includes tumor depth, presence of ulceration, number of mitotic figures, and presence or absence of microsatellites. However, numerous studies have found many other factors that are not included in the AJCC classification but that are nevertheless of prognostic significance. We discuss these factors in this paper.

Protocol for the Histologic Diagnosis of Cutaneous Melanoma: Consensus Statement of the Spanish Society of Pathology and the Spanish Academy of Dermatology and Venereology (AEDV) for the National Cutaneous Melanoma Registry. / Protocolo de diagnóstico histológico para muestras de pacientes con melanoma cutáneo. Documento de consenso de la SEAP y la AEDV para el Registro Nacional de Melanoma.

This article describes a proposed protocol for the histologic diagnosis of cutaneous melanoma developed for the National Cutaneous Melanoma Registry managed by the Spanish Academy of Dermatology and Venereology (AEDV). Following a review of the literature, 36 variables relating to primary tumors, sentinel lymph nodes, and lymph node dissection were evaluated using the modified Delphi method by a panel of 8 specialists (including 7 pathologists). Consensus was reached on the 30 variables that should be included in all pathology reports for cutaneous melanoma and submitted to the Melanoma Registry. This list can also serve as a model to guide routine reporting in pathology departments.

Granulomas in Dermatopathology: Principal Diagnoses - Part 1. / Granulomas en dermatopatología: principales entidades. Parte I.

This series of 2 articles on dermatopathologic diagnoses reviews conditions in which granulomas form. Part 1 clarifies concepts, discusses the presentation of different types of granulomas and giant cells, and considers a large variety of noninfectious diseases. Some granulomatous diseases have a metabolic origin, as in necrobiosis lipoidica. Others, such as granulomatous mycosis fungoides, are related to lymphomas. Still others, such as rosacea, are so common that dermatologists see them nearly daily in clinical practice.

Granulomas in Dermatopathology: Principal Diagnoses - Part 2. / Granulomas en dermatopatología: principales entidades. Parte II.

Part 2 of this series on granulomatous diseases focuses on skin biopsy findings. Whereas the first part treated noninfectious conditions (metabolic disorders and tumors, among other conditions), this part mainly deals with various types of infectious disease along with other conditions seen fairly often by clinical dermatologists.

Clinical and Histopathologic Characteristics of the Main Causes of Vascular Occusion - Part II: Coagulation Disorders, Emboli, and Other. / Dermatopatología de la oclusión intraluminal vascular: parteII (coagulopatías, émbolos y miscelánea).

Vascular occlusion has multiple, diverse clinical manifestations, some of which can have grave consequences for patients. It also has a wide variety of causes, including thrombi, which we recently addressed in partI of this review. In this second part, we look at additional causes of vascular occlusion.

Clinical and Histopathologic Characteristics of the Main Causes of Vascular Occlusion - Part I: Thrombi. / Dermatopatología de la oclusión intraluminal vascular: parte I (trombos).

Vascular occlusion has multiple, diverse clinical manifestations, some of which can have grave consequences for patients. The causes of vascular occlusion are also highly variable, ranging from thrombi triggered by the uncontrolled activation of coagulation mechanisms, on the one hand, to endothelial dysfunction or occlusion by material extrinsic to the coagulation system on the other. In a 2-part review, we look at the main causes of vascular occlusion and the key clinical and histopathologic findings. In this first part, we focus on vascular occlusion involving thrombi.