Most Cited

In recent weeks, several reports have emerged of skin lesions with different clinical presentations in COVID-19 cases. All dermatologists should be aware of these cutaneous lesions, which may be early clinical symptoms of infection. We reviewed the l...

Our knowledge in vascular anomalies has grown tremendously in the past decade with the identification of key molecular pathways and genetic mutations that drive the development of vascular tumors and vascular malformations. This has led us to better...

Immunohistochemical stains are increasingly used to aid in the diagnosis of malignant melanoma, especially when the differentiation of the tumor is unclear based on examination with hematoxylin and eosin. However, aberrant expression of non-melanocyt...

Skin tumors, especially melanoma, which is highly aggressive and progresses quickly to other sites, are an issue in various parts of the world. Nevertheless, the one and only way to save lives is to detect it at its initial stages. This study explore...

In recent years, an increasing enthusiasm has been observed towards artificial intelligence and machine learning, involving different areas of medicine. Among these, although still in the embryonic stage, the dermatopathological field has also been p...

Background: neck cysts are frequently encountered in pediatric medicine and can present a diagnostic dilemma for clinicians and pathologists. Several clinical items enable to subclassify neck cyst as age at presentation, anatomical location, includin...

Contemporarily to the new SARS-CoV-2 mediated COVID-19 pandemic, a rise in patients with acral chilblain lesions has been described. They manifest late after mild disease or asymptomatic exposure to SARS-CoV-2. Their pathogenic evolution is currently...

(1) Background: Coronavirus disease 2019 (COVID-19) vaccines are currently employed on a population-wide scale in most countries worldwide. Data about unusual cutaneous adverse drug reactions (ADR) are scant, though. (2) Methods: We retrospectively a...

Primary cutaneous gamma-delta T cell lymphomas (PCGDTCLs) are rare and aggressive cutaneous malignancies that have been diagnostically challenging for dermopathologists and clinicians since their first published descriptions in 1991. Since then, the...

Dermatofibrosarcoma protuberans (DFSP) is a dermal malignant mesenchymal tumor. Most variants are associated with a high risk of local recurrence and a low risk of metastasis. The classic histomorphology of this tumor is made up of uniform, spindle-s...

Hidradenitis suppurativa (HS) is a chronic inflammatory scarring disease felt to be related to occlusion of the hair follicle unit in intertriginous areas. We perform a systematic review on HS histopathology to evaluate current knowledge and discuss...

Ichthyoses are inborn keratinization disorders affecting the skin only (non-syndromic) or are associated with diseases of internal organs (syndromic). In newborns, they can be life-threatening. The identification of the gene defects resulted in recla...

This literature review introduces the integration of Large Language Models (LLMs) in the field of dermatopathology, outlining their potential benefits, challenges, and prospects. It discusses the changing landscape of dermatopathology with the emerge...

Acral melanocytic neoplasms, including acral melanocytic nevus and acral melanoma, are common melanocytic lesions in Asian populations. Both lesions occur on the volar surface of the hands and feet, and on nail units. Acral melanocytic nevi occur on...

The first description of histopathological variants of neurofibroma dates back to 1994. Over the years, many individual case reports elucidating unusual histologic features in neurofibroma have been added to the literature, some of which have defined...

Neoplasms of sweat glands and the breast may be morphologically and immunophenotypically similar. A recent study showed that TRPS1 staining is a highly sensitive and specific marker for breast carcinoma. In this study, we analyzed TRPS1 expression in...

Background: Cutaneous adverse drug reaction (CADR) is common in both inpatient and outpatient clinical settings and has been associated with a large variety of medications. Drug reactions represent a significant burden to the healthcare system due to...

Mucocutaneous adverse events are commonly observed under immune checkpoint inhibitors (ICIs) therapy. Here, we report the case of a 43-year-old male patient with a stage IIIC melanoma disease who developed hidradenitis suppurativa (HS) three months a...

Tuberous Sclerosis Complex (TSC) is a multisystem genetic disease characterized by cutaneous and extracutaneous hamartomas. The diagnosis is based on the association of major and minor criteria, defined by a consensus conference updated in 2012. The...

Year after year, the incidence and prevalence rates of cutaneous Malignant Melanoma (MM) show a continuous increase and, according to the most up-to-date American Cancer Society (ACS) projections, it is estimated that 97,610 new melanomas will be dia...

Considerable controversy exists within the field of dermatopathology in differentiating keratoacanthoma (KA) from squamous-cell carcinoma (SCC). KAs are rapidly growing, benign squamous tumors that are typically well differentiated. This controversy...

Atopic dermatitis is a multifactorial pathology that includes perturbations of gene expression and increased adhesion of Staphylococcus aureus. Fucoidans are seaweed-derived sulfated fucose-rich polysaccharides that are known to be anti-inflammatory...

Direct immunofluorescence is a vital diagnostic test for assessing vesiculobullous disorders, vasculitides, and connective tissue diseases. It is a robust and valuable technique that offers essential diagnostic information for many critical dermatose...

Panniculitides form a heterogenous group of inflammatory diseases that involve the subcutaneous adipose tissue. These disorders are rare in children and have many aetiologies. As in adults, the panniculitis can be the primary process in a systemic di...

Dedifferentiated melanoma is a particular form of malignant melanoma with a progressive worsening of the patient’s clinical outcome. It is well known that melanoma can assume different histo-morphological patterns, to which specific genetic signature...

Erosive pustular dermatosis of the scalp (EPDS) is an uncommon, pustular, idiopathic disorder typically occurring on the scalp of the elderly, whose diagnosis requires close clinicopathologic correlations. Recently, the primary histopathologic charac...

Neurofibromatosis type 1 (NF1) is a common genetic disease whose dermatological lesions are at the forefront of its development. Cutaneous manifestations include café au lait spots, intertriginous freckling, and neurofibromas which appear duri...

Background: The earliest cases of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, in December 2019. Since the declaration as a pandemic on 11 March 2020, further dermatological conditions continue to be documente...

Background: Rhabdoid melanoma is a rare variant of malignant melanoma with characteristic cytomorphologic features. Due to the potential loss of conventional melanocytic markers, histopathologic diagnosis is often challenging. We hypothesize that imm...

Background: The most common autoimmune blistering disease, bullous pemphigoid (BP), shows an increased prevalence in psoriatic patients and oncologic patients undergoing immune-checkpoint blockade (ICB). Even though the same autoantigens (BP180/BP230...

Background: Fibrotic diseases pose a problem for overall health due to their chronic, progressive nature; the lack of a cure; and the fact that such conditions are largely refractory to current medical and surgical treatment practices. Objective: The...

Dupilumab is a humanized IgG4 monoclonal-antibody that is approved by the United States Food and Drug Administration (FDA) for the treatment of moderate-to-severe atopic dermatitis (AD) in patients aged 12 years and older. In recent years, several ca...

A clinical risk is an inherent risk in healthcare processes, including skin biopsy procedures, and may lead to misdiagnoses, increased healthcare costs and potential harm to patients. Indeed, clinical and histopathological data must be integrated if...

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a very rare entity of soft tissue considered a “neoplasm of uncertain behaviour of connective or other soft tissue” by the World Health Organization (2020). It develops in subcutaneous tissue of the...

Low-grade myofibroblastic sarcoma (LGMS) is a mesenchymal tumor of myofibroblasts that occurs more frequently in adults. A series of three cases is presented to illustrate that LGMS may also occur within the oral cavity in children and adolescents. T...

(1) Background: Endocrine Mucin-Producing Sweat Gland Carcinoma (EMPSGC) is a rare, low-grade, neuroendocrine-differentiated, cutaneous adnexal tumor, officially recognized by the World Health Organization (WHO) Skin Tumors Classification in 2018 as...

Ulcerations of the lower extremities are a frequently encountered problem in clinical practice and are of significant interest in public health due to the high prevalence of underlying pathologies, including chronic venous disease, diabetes and perip...

Melanoma is among the most aggressive tumors, with different histological patterns of presentation ranging from the usual and easily diagnosable pictures to complex patterns of difficult diagnostic interpretation. Here, we present three cases of a ve...

Maculopapular exanthem is a commonly encountered presentation in routine clinical practice, and differentiation between its two most common etiologies, i.e., viral- and drug-induced, often poses a diagnostic dilemma. Clinical, hematological and bioch...

Petrified ears is an uncommon clinical entity. It describes auricular cartilage hardening, due usually to ectopic calcification or, less commonly, ossification. The most common causes are frostbite and mechanical trauma. However, endocrinopathies hav...

Multiple papulonodular skin lesions at birth can indicate the presence of various benign and malignant disorders. Although the lesions’ clinical aspect (color and consistency, in particular) may steer the clinician towards one disorder or another (in...

Background: balloon cell melanoma represents less than 1% of all histological forms of malignant melanoma and represents a diagnostic challenge for the dermatopathologist. Methods: in this paper we present our cases of BCM found in our daily practice...

The diagnosis of cutaneous and subcutaneous spindle cell neoplasms in children is often challenging and has potential therapeutic and prognostic implications. Although correctly diagnosing dermatofibrosarcoma protuberans and infantile fibrosarcoma is...

In recent years, researchers have explored potential uses for artificial intelligence (AI) in medical practice [...]

Primary localized cutaneous nodular amyloidosis (PLCNA) is a rare condition due to the plasma cell proliferation and skin deposition of immunoglobulin light chains, without systemic amyloidosis or hematological dyscrasias. The association with autoim...

Immunohistochemical quantification of inflammatory cells in skin biopsies is a valuable tool for diagnosing skin diseases and assessing treatment response. The quantification of individual cells in biopsies is time-consuming, tedious, and difficult....

Early detection of skin cancer is of critical importance to provide five year survival rates that approach 99%. By 2050, one out of five Americans by age 70 will develop some form of skin cancer. This will result in a projected rate of 50 million ski...

Background: Extranodal NK/T cell lymphoma, nasal type (ENK/T) with cutaneous involvement has various histopathological findings and diverse clinical manifestations. Methods: A retrospective study of cutaneous involvement of ENK/T lymphoma between 200...

Scar endometriosis or incisional endometriosis is the presence of endometrial tissues with glands in the previous incision or scar. Its overall estimated incidence after post-cesarean and post-hysterectomy is 0.03–0.4% and 1.08–2%, respec...

Senile gluteal dermatosis (SGD) is a common but seldom recognized condition. It is characterized clinically by unilateral or bilateral hyperkeratotic, lichenified plaques on the gluteal area, being attributed to prolonged sitting, particularly in the...