Apocrine Chromhidrosis
We present the case of a 65-year-old woman who presented with a sudden onset of pink sweating affecting mainly her axillae but also her pelvis, causing staining of clothing and bed sheets. There was nil to note on examination and histology with immunostaining demonstrated focally prominent yellow-brown lipofuscin granules in the cytoplasm of the apocrine secretory cells confirming the diagnosis. The disease can have a significant psychosocial impact, and treatment remains challenging. Our case is unique because the red and pink coloring of sweat is less common in cases of apocrine chromhidrosis, which is often in favor of ...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Syphilitic Chancre of the Lip
We present a case of a chancre presenting on the lip of a nonimmunocompromised 55-year-old male patient with immunohistochemical confirmation. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Persistent Plaque on the Scalp With Cutis Verticis Gyrata–Like Features: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

A 47-Year-Old Patient With Multiple Desquamative Patches and Subsequent Onset of Papular Lesions: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Persistent Unilateral Orofacial Edema: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Widespread Keratotic Spiky Follicular Papules Associated With Hyperpigmentation: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Does a Biological Continuum Between Nodular (Apocrine) Hidradenoma and Adenomyoepithelioma Really Exist?
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Letters to the Editor Source Type: research

Balloon Is Exceptional, Balloon In Situ Even More!
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Letters to the Editor Source Type: research

Persistent Plaque on the Scalp With Cutis Verticis Gyrata–Like Features: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

A 47-Year-Old Patient With Multiple Desquamative Patches and Subsequent Onset of Papular Lesions: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Persistent Unilateral Orofacial Edema: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Widespread Keratotic Spiky Follicular Papules Associated With Hyperpigmentation: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Neonatal Autoimmune Subepidermal IgG/IgA Blistering Disease With Severe Laryngeal and Esophageal Involvement: A Report of a Case and Review of the Literature
We describe a neonate with subepidermal cutaneous blistering disease with severe laryngeal and esophageal involvement leading to acute respiratory distress. Histopathology demonstrated a subepidermal blister with neutrophils and eosinophils at the dermal base. Collagen IV was detected at the dermal floor, and direct immunofluorescence showed linear IgG, IgA, and C3 deposits at the basement membrane zone. The patient demonstrated markedly increased serum levels of anti-BP180 NC16A and anti-BP230 IgG antibodies (Abs) but failed to show anti-LAD-1 IgA Abs. His healthy mother showed serum anti-LAD-1 IgA Abs but did not show an...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Longstanding Eccrine Syringofibroadenoma With Evidence of Carcinomatous Transformation
We present a case of ESFA showing areas of carcinomatous transformation, discussing its morphological and immunohistochemical findings. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Lymphomatoid Papulosis With a Unique T Follicular Helper–Like Phenotype
We report an unusual case of LyP displaying a T follicular helper cell–like phenotype and histopathologically resembling the primary cutaneous CD4-positive small-sized to medium-sized T-cell lymphoproliferative disorder. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Focal Dermal Elastosis: A Proposed Update to the Nomenclature
We present a case of a 59-year-old woman with this disorder. To reflect the broad age range of patients affected by this disorder, we propose the term “focal dermal elastosis.” (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Hansen Disease (Leprosy) and Armadillo Exposure in Arkansas: A Case Series
Conclusions: Direct exposure to armadillos does not appear to be required for transmission of HD making a soil-mediated mechanism of indirect exposure plausible. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Morphea With Keloidal Features: A Case Report and Review of the Literature
We report a 34-year-old woman with a medical history of asthma and Raynaud's phenomenon, presented for the evaluation and management of multiple erythematous hyperpigmented annular plaques reportedly developed after taking trimethoprim/sulfamethoxazole. An initial skin biopsy showed findings supportive of a drug eruption. She was treated with oral prednisone and achieved some improvement. She presented 1 year later with enlargement of the plaques and emergence of new lesions. Skin biopsies revealed an unremarkable epidermis with marked fibrosis of the mid-to-deep dermis with sparing of the papillary dermis, and superficial...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Brief Report Source Type: research

A Rare Perineurioma/Granular Cell Tumor Hybrid Peripheral Nerve Sheath Tumor
We present a rare hybrid of perineurioma and granular cell tumor and review the literature. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Brief Report Source Type: research

Aluminum Chloride–Induced Apoptosis Leads to Keratinization Arrest and Granular Parakeratosis
The objective of this study is to elucidate the skin effect of topical aluminum application using a mouse model. We sprayed 20% aluminum chloride every day on the depilated mice skin and analyzed the skin clinically, histopathologically, and immunohistologically. We have succeeded in the histological replication of GP on mouse skin. The basophilic granules in the stratum corneum contained filaggrin, and processing of profilaggrin to filaggrin was disrupted in aluminum-treated mouse skin (Al-mouse). In Al-mouse, cytochrome c and cleaved-caspase 3 were upregulated mainly in the granular layer, and caspase 3 p20 subunit was u...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Original Study Source Type: research

Sporotrichosis: A Clinicopathologic Study of 89 Consecutive Cases, Literature Review, and New Insights About Their Differential Diagnosis
Conclusions: The sporotrichosis cases underwent both cumulative and linear growth, especially in the group above 60 years. Squamous cell carcinomas appeared several times as a misdiagnosis of sporotrichosis by dermatologists, so it should be considered as an important differential diagnose due to the current context of skin cancers. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Original Study Source Type: research

Erythema Migrans and Interface Changes: More Than a Fortuitous Association
In this study, cases submitted with a serologically confirmed, clinically unequivocal, or highly suspicious diagnosis of ECM/Lyme disease between January 01, 2016, and September 01, 2018, were retrieved from the electronic database system and reviewed to delineate the histopathologic features of ECM. The series consisted of 14 cases. A superficial perivascular lymphocytic infiltrate was noted in all biopsies, accompanied by a deep and/or interstitial inflammatory infiltrate in 9 cases (64%). The inflammation ranged from relatively sparse to dense and prominent. At least focal interface changes were noted in 12 biopsies (86...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Original Study Source Type: research

Three Types of Nodal Melanocytic Nevi in Sentinel Lymph Nodes of Patients With Melanoma: Pitfalls, Immunohistochemistry, and a Review of the Literature
Abstract: The presence or absence of metastasis in sentinel lymph nodes often drives melanoma staging, prognosis, and treatment. However, distinguishing between metastatic melanoma cells and clusters of benign melanocytic nevus cells is not always straightforward. When morphologic hematoxylin and eosin interpretation alone is not sufficient, additional hematoxylin and eosin sections and immunohistochemical (IHC) studies may be beneficial. This review and small cases series of 3 diagnostically challenging melanocytic sentinel lymph node cases highlights the IHC approach to evaluate intraparenchymal nodal melanocytic nevi,...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Original Study Source Type: research

Joseph von Gerlach—A Reminder of One of the Pioneers of Histochemistry on the Occasion of His 200th Birthday
Abstract: Joseph von Gerlach was an eminent German anatomist and pioneer of histology. He devised various techniques to assess the fine structure of tissues, most notably a procedure of staining histologic sections that marked the beginning of routine staining in histology. Gerlach was also one of the pioneers of microphotography. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: Dermatopathology in Historical Perspective Source Type: research

Neutrophilic Infiltrates in Panniculitis: Comprehensive Review and Diagnostic Algorithm Proposal
Abstract: Neutrophilic infiltrates in panniculitis can be seen in different clinical–pathological entities. There are a “mostly neutrophilic inflammatory infiltrate” in some entities classically defined as neutrophilic panniculitis and already included in algorithms, such as enzymatic panniculitis, infective and factitial ones, erythema induratum, or subcutaneous Sweet syndrome, but there are also other panniculitis where neutrophils are frequently observed such as panniculitis associated with inflammatory bowel disease or rheumatoid arthritis, or drug-induced panniculitis associated with BRAF inhibitor...
Source: The American Journal of Dermatopathology - September 23, 2020 Category: Pathology Tags: CME Article Source Type: research

Clear Cell Sarcoma With Cutaneous Presentation in a 4-Year-Old Boy
We report a case of a 4-year-old Brazilian boy, who presented with an erythematous and painful nodule involving the skin of his left arm. Immunohistochemistry was performed for S100, SOX10, CD34, desmin, SMA, HMB-45, CD1a, and CD163, and fluorescence in situ hybridization for EWSR1 gene rearrangement using a break-apart probe was completed. Immunohistochemistry showed bland spindle cells with “floret-like” appearance simulating a giant cell fibroblastoma; tumor cells were positive for S100 and SOX10; neoplastic cells were negative for CD34, desmin, SMA, HMB-45, CD1a, and CD163; and fluorescence in situ hybridiz...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Cutaneous Adenosquamous Carcinoma of the Scalp With Intestinal Phenotype
We report here an exceptional case of cutaneous adenosquamous carcinoma which showed immunohistochemically features of intestinal differentiation, namely because of the expression of keratin 20 and CDX2, a marker of gastrointestinal tumors. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

A 40-Year-Old Woman With Hypopigmented Patches and a New Papular Rash: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Rash Associated With Arthritis and Pleuritic Chest Pain: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

A 70-Year-Old Man With Raspberry-Like Tumors on the Nipples: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Veritable Vascular Changes: Challenge
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Source Type: research

Hydroa Vacciniforme–Like Lymphoproliferative Disorder With Progression to EBV+ Cytotoxic Peripheral T-Cell Lymphoma
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Letters to the Editor Source Type: research

Ates D, Kosemehmetoglu K. Acquired Leukonychia of the Distal Nail Plate: A Morphologic and Proteomic Analysis. Am J Dermatopathol 2019, 00: 1–4
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Letters to the Editor Source Type: research

A 40-Year-Old Woman With Hypopigmented Patches and a New Papular Rash: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Rash Associated With Arthritis and Pleuritic Chest Pain: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

A 70-Year Old Man With Raspberry-Like Tumors on the Nipples: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Veritable Vascular Changes: Answer
No abstract available (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Clinical Pathologic Challenge Answer Source Type: research

Metastatic Prostatic Adenocarcinoma in Patient With Muir–Torre Syndrome Misdiagnosed as Metastatic Sebaceous Carcinoma: Case Report and Systematic Literature Review
We present the case of a 63-year-old man with several cutaneous and visceral neoplasias in the context of MTS, and a pelvic lymph node lesion diagnosed initially as metastatic sebaceous carcinoma, but later identified as metastasis from a newly diagnosed prostatic adenocarcinoma. Histological similarities between these 2 lesions are discussed. A systematic literature review was conducted evaluating all published cases of patients with MTS in which metastases were reported. Eighteen articles were included in the final synthesis, representing 20 patients with a total of 26 metastases. Seventeen patients (85%) exhibited metas...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

SOX-10 and S100 Negative Desmoplastic Melanoma: Apropos a Diagnostically Challenging Case
Abstract: An 83-year-old man presented with a tumor of the neck, clinically consistent with an epidermal inclusion cyst. Excisional biopsy revealed a deeply infiltrating spindled cell tumor. Immunohistochemical markers for S100, SOX-10, Melan-A, HMB-45, and NK1/C3 were negative. Based on the presence of an area of lentigo maligna and the histologic pattern of the spindle cell component, a diagnosis of desmoplastic melanoma was made despite the absence of immunophenotypic evidence for melanocytic differentiation. To the best of our knowledge, the complete lack of both S100 and SOX-10 makes this tumor an unprecedented case...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Melanocytic BAP-1–Mutated Atypical Intradermal Tumor in Two Siblings: A Case Report
We present a case of 2 siblings with MBAITs and their future management. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Angiomatoid Fibrous Histiocytoma With ALK Expression in an Unusual Location and Age Group
Abstract: Angiomatoid fibrous histiocytoma (AFH) is a relatively rare soft tissue tumor of intermediate malignant potential, occurring most commonly in young adults, with a recognized propensity for local recurrence and occasional metastasis. A case of AFH occurring on the finger of a 60-year-old man is described in which the unusual location and age group for this entity raised the original wrong diagnosis of an aneurysmal and cellular fibrous histiocytoma. Further workup demonstrated an EWSR1-CREB1 translocation, confirming the correct diagnosis of AFH. Strong anaplastic lymphoma kinase (ALK) expression using the antib...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Does a Subset of Localized Chronic Fibrosing Vasculitis Represent Cutaneous Manifestation of IgG4-Related Disease/a Histologic Pattern of IgG4-Related Skin Disease? A Reappraisal of an Enigmatic Pathologic Entity
Abstract: Localized chronic fibrosing vasculitis (LCFV) is a rare cutaneous fibroinflammatory and vasculitic process of poorly defined etiology. Furthermore, controversy remains as to whether LCFV represents a primary pathologic process or a histologic pattern. The current case documents a 52-year-old male patient with a scrotal mass and clinical history of a retroperitoneal mass as well as a previously resected tumor of the right submandibular salivary gland displaying morphologic features of eosinophilic angiocentric fibrosis. Histologic examination of the resected scrotal mass revealed a tumefactive lesion characteriz...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Rosai–Dorfman Disease–Like Reaction to Tattoo
Abstract: A 47-year-old white man presented with a 14-month history of an asymptomatic 2-cm, slow-growing nodular lesion on his left shin that arose in the background of a black tattoo. An excisional biopsy followed by histological examination revealed a prominent lymphohistiocytic infiltrate, with many large, foamy histiocytic cells containing intact inflammatory cells within their cytoplasm, findings consistent with emperipolesis, a feature typical of Rosai–Dorfman disease (RDD). By immunohistochemistry, S-100 (a marker that is positive in almost all cases of RDD) was negative, arguing against the diagnosis of RD...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Extraordinary Case Report Source Type: research

Peripheral Palisading in Melanoma Mimicking Basal Cell Carcinoma: A Case Report
Abstract: The incidence of melanoma has been increasing over the past few decades. Because of its phenotypic diversity, melanoma may present in various clinical and histopathological manifestations, and it can mimic varieties of skin lesions from benign to malignant and from epithelial to nonepithelial. Accurate diagnosis of melanoma is crucial because delayed treatment leads to worse prognoses. Here, we describe a case of melanoma in an 82-year-old man with an unusual histopathologic presentation, namely, the presence of neoplastic aggregates with a palisaded periphery resembling basal cell carcinoma. (Source: The Ameri...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Brief Report Source Type: research

Cluster of Vacuolated Spinous Keratinocytes: A Clue to Cornoid Lamellation and a Case of Porokeratosis Disseminata
Abstract: Cornoid lamella is a definitive diagnostic feature of porokeratosis, a disorder of keratinization that has various different clinical presentations. A tiered column of parakeratosis and a diminished granular layer with dyskeratotic keratinocytes at the column base are all useful and known features of cornoid lamellation. We have found a cluster of vacuolated spinous cells to be a reliable fourth feature of cornoid lamellation and a feature when present alone to be a reliable sign of impending cornoid lamellation on deeper sections. Furthermore, we present a novel clinical phenotype of disseminated papular porok...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Original Study Source Type: research

Pseudocarcinomatous Hyperplasia, Squamous Cell Carcinoma, and Keratoacanthoma Associated to Lymphomas of the Skin and External Mucous Membranes: A Case Report and Literature Review
We present a case of single lesion mycosis fungoides (Woringer-Kollop's reticulosis pagetoid) associated with PCH that was initially misdiagnosed as squamous cell carcinoma (SCC) and review all PubMed-indexed previously reported cases on lymphomas of the skin or external mucous membranes associated to PCH, SCC, and keratoacanthomas. Including our own case, we collected data of 114 cases of cutaneous or mucosal lymphoproliferative disorders associated to PCH, 3 cases associated to SCC, and other 3 cases associated to keratoacanthomas. All cases were tabulated to the following parameters whenever data was available: sex, age...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Original Study Source Type: research

Fragmented Elastic Fibers in Focal Dermal Hypoplasia (Goltz–Gorlin Syndrome) Without Focal Dermal Hypoplasia: Report of a Male Case and Review of the Literature
We report the case of a 51-year-old man presenting with congenital skin lesions, syndactyly, facial and thoracic asymmetry, inguinal and laryngeal papillomas, cryptorchidism, polythelia, and dental anomalies. Molecular genetic analysis confirmed the clinically suspected diagnosis of GGS by detecting a known pathogenic mutation in the PORCN gene, c.502G>A [p.(Gly168Arg)] in the mosaic state. Histopathological examinations of skin biopsies of affected individuals typically show focal dermal hypoplasia and fat herniation; despite numerous skin biopsies, these characteristics were not found in the patient involved. Instead,...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Original Study Source Type: research

Pseudolipomatosis Cutis: A Retrospective Case Series of Skin Biopsies Showing a Distinctive Vacuolar Artifactual Change
We describe this change in a series of skin biopsies clustered over 2 periods, November 2017–December 2017 and February 2019. Hematoxylin and eosin-stained sections from 21 skin biopsies were examined by 2 dermatopathologists. Variable-sized vacuoles were noted in the epidermis, dermis, and/or subcutaneous fat in all biopsies. Vacuoles were seen in the stratum corneum in 2 biopsies, epidermis in 15 biopsies, papillary dermis in 19 biopsies, reticular dermis in 20 biopsies, and subcutis in 9 biopsies. The vacuoles resembled a true histological change in many biopsies: vacuolated keratinocytes (n = 6), basal cell vacuo...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Original Study Source Type: research

Retrospective Cohort: Genomic Differences Between Pigmented Spindle Cell Nevi of Reed and Reed-Like Melanomas
Conclusions: In diagnostically challenging cases, ancillary IHC studies can assist in distinguishing PSCN from RLM. Our study suggests positive staining by IHC for BRAF V600E and older age strongly favors a diagnosis of RLM. (Source: The American Journal of Dermatopathology)
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: Original Study Source Type: research

Morphologic Diversity of Merkel Cell Carcinoma
Abstract: Merkel cell carcinoma (MCC) is a rare and highly aggressive neuroendocrine carcinoma of unknown origin. We performed a retrospective histologic review of primary cutaneous MCCs diagnosed from 1997 to 2018 in several clinical institutions and literature review to determine the frequency of various unusual morphologic appearances of MCC. Of the 136 primary MCCs identified, intraepidermal carcinoma or epidermotropism was noted in 11/136 (8%) cases. An association with pilar cyst in 1/136 (0.7%) case, with actinic keratosis in 2/136 (1.5%) cases, with either invasive or in situ squamous cell carcinoma (SCC) in 14/1...
Source: The American Journal of Dermatopathology - August 22, 2020 Category: Pathology Tags: CME Article Source Type: research