[Translated article] Histopathologic and Trichoscopic Correlations in Nonscarring Alopecias.

Trichoscopy is an essential tool in the evaluation of alopecia. The current compilation of trichoscopic signs in this setting helps distinguish between different forms of hair loss and has improved our understanding of the pathogenic mechanisms involved. The trichoscopic signs are always linked to the pathogenic mechanisms of the alopecia being examined. We examine correlations between the main trichoscopic and histopathologic findings in nonscarring alopecias.

Modern Concepts in Melanocytic Tumors. / Conceptos modernos en tumores melanocíticos.

The advent of molecular pathology has fueled unprecedented advances in the diagnosis and understanding of melanocytic tumors. These advances, however, have also generated concepts that may be difficult to grasp for clinical practitioners, who are not always conversant with the array of genetic techniques employed in the laboratory. These same practitioners, however, are being increasingly called on to provide treatments that are often based on the latest molecular findings for melanocytic tumors. We review the most recent concepts in the pathway classification of melanocytic tumors, including intermediate lesions known as melanocytomas. We examine the genetic and molecular techniques used to study these tumors, look at where they overlap, and discuss their limitations and some of the most difficult-to-interpret results.

Vascular Malformations: A Histopathologic and Conceptual Appraisal. / [Artículo traducido] Malformaciones vasculares: un enfoque histopatológico y conceptual.

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

Vascular Malformations: A Histopathologic and Conceptual Appraisal.

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

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.

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.

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.

Skin Biopsy in the Context of Systemic Disease. / La biopsia cutánea en el contexto de la enfermedad sistémica.

The skin is the largest and most exposed organ in the human body and the ideal place to look for signs that aid in the early diagnosis of systemic diseases with cutaneous effects. As the concepts that underpin our understanding of many of these diseases have evolved or expanded in recent years, there have also been changes in the criteria we use for early diagnosis, including our approaches to skin biopsy and dermatopathologic evaluation. This review focuses on some of the systemic processes with skin manifestations for which our basic understanding has changed most in recent decades.

Cutaneous metastases from breast carcinoma: calretinin expression and estrogen, progesterone and Her2/neu status of the metastases, compared to primary cutaneous apocrine tumors.

Recently, it has been demonstrated how apocrine glands, as well as several cutaneous apocrine tumors, do not express calretinin. In the current report, we studied calretinin immunoexpression in 33 cases of cutaneous metastases of ductal breast carcinoma, as well as in seven primary cutaneous apocrine tumors. We also tested the hormonal status of all cases for estrogen receptors (ER), progesterone receptors (PR), and ERRB2. From the 33 metastases, 26 (78.79%) cases were calretinin-negative and seven cases expressed the marker. Five (15.15%) cases were triple-negative (ER-, PR-, Herceptest-). Of these five cases, three cases were calretinin+ and two cases were calretinin-. Three out of the seven cases that expressed calretinin were triple-negative. From the seven primary cutaneous apocrine tumors, only one showed focal expression of calretinin, and six of them showed a triple-negative immunophenotype. Only the ER+, PR+ case showed morphologic features on an "in situ" apocrine carcinoma. We concluded that our findings support the value of calretinin in the differential diagnosis between a metastasis from breast carcinoma into the skin and a primary cutaneous apocrine carcinoma (CAC), especially in triple-negative cases. However, hormonal markers plus calretinin would not be sufficient to discriminate between both diagnostic possibilities, and they are probably better used when integrated in a wide immunohistochemical panel.

The use of immunohistochemistry in the evaluation of the nail matrix in biopsies of ingrown toenails.

The success of surgical approaches to ingrown toenails depends on the extraction (either partial or total) of the nail matrix. The identification of the nail matrix in specimens taken from ingrown toenails is not always easy because of the fragmentation of the biopsies, difficulties in matrix orientations and the heavy inflammatory infiltrate. In biopsies taken from polydactyly surgeries, the matrix shows a peculiar pattern of expression of the CD10 and CD34 markers that differs from the one shown by the lateral nail fold. We investigated whether such a pattern was also found in biopsies from ingrown toenails, which can be greatly distorted through inflammation and fibrosis. We examined 15 biopsies from cases of ingrown toenails at different clinical stages. We performed routine Hematoxylin-Eosin studies, as well as immunohistochemical studies with CD10, CD34, HMB-45 and Melan-A. The morphologic changes in all cases were typical of those found in ingrown toenails and their intensities correlated with the clinical stages. Matrical keratinization was identified in all of the biopsies. Morphologic features that are compatible with the lateral nail fold were also seen in seven of the 15 biopsies. In five cases, an intermediate area of transition between matrix and lateral nail folds was heavily distorted by inflammatory changes. Melanocytic markers showed scattered intra-epidermal cells in all but one case. HMB-45 and Melan-A were equally good in demonstrating the melanocytic population. We concluded that the expression of CD10 and CD34 in cases of ingrown toenails is preserved and it follows the pattern described in nails from polydactyly. Therefore, both markers can be useful in fragmented specimens taken from surgeries for ingrown toenails, in order to confirm the removal of the nail matrix.