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Ocular Oncology and Pathology Aug 2019Large cell acanthoma (LCA) was first described as a lesion on sun-exposed skin. All LCAs feature keratinocytes twice the size of normal cells (cytomegaly). Although...
Large cell acanthoma (LCA) was first described as a lesion on sun-exposed skin. All LCAs feature keratinocytes twice the size of normal cells (cytomegaly). Although infrequently diagnosed in the skin, it has been even more rarely described by ophthalmic pathologists in the eyelid skin and the conjunctiva. This report describes the third case of a conjunctival epithelial LCA, with the first published clinical photograph highlighting its leukoplakic and well-circumscribed character, as well as the most thorough analysis of the immunohistochemical features of this lesion. It is contrasted with squamous dysplasias and papillomas of the conjunctiva. A review of previous conjunctival LCA lesions discloses frequent recurrences after initial surgery and the remote but real potential for squamous dysplastic transformation. Immunohistochemical stains for certain cytokeratins, p53, and Ki-67 (proliferation index) will in the future be particularly helpful in establishing an early and accurate diagnosis of conjunctival LCA.
PubMed: 31559241
DOI: 10.1159/000495250 -
Dermatology Practical & Conceptual Oct 2021The differential diagnosis of lesions excised to exclude melanoma include a variety of benign and malignant melanocytic and non-melanocytic lesions.
INTRODUCTION
The differential diagnosis of lesions excised to exclude melanoma include a variety of benign and malignant melanocytic and non-melanocytic lesions.
OBJECTIVES
We examined the variability between pathologists in diagnosing non-melanocytic lesions.
METHODS
As part of a larger study prospectively examining the diagnosis of lesions excised to exclude melanoma in 198 patients at a primary care skin cancer clinic in Newcastle, Australia, we compared diagnosis made by 5 experienced dermatopathologists, of 44 non-melanocytic lesions in 44 patients aged 22-90.
RESULTS
Forty-four lesions (out of 217 in total) were non-melanocytic. Among the 5 pathologists who examined each case there was marked variability in the terminology used to diagnose each case. The most common variability was found between seborrheic keratosis, large cell acanthoma, solar lentigo, and lichenoid keratosis. The diagnosis made by the majority of the pathologists was deemed to be the reference diagnosis. Versus majority diagnosis, 4% of benign lesions were considered malignant, and 7% of malignant diagnoses were considered as benign.
CONCLUSIONS
The different terminology adopted and lack of consensus in the diagnosis of these non-melanocytic lesions in this setting suggests that training AI systems using gold standards may be problematic. We propose a new management classification scheme called MOLEM (Management of Lesions Excised to exclude Melanoma) which expands the previously described MPATH-dx to include non-melanocytic lesions.
PubMed: 35024222
DOI: 10.5826/dpc.1104a94 -
The American Journal of Dermatopathology May 2024Onychocytic matricoma (OCM) is a benign neoplasm of the nail matrix. Only 18 cases of this tumor have been reported in the literature to date. We retrospectively...
Onychocytic matricoma (OCM) is a benign neoplasm of the nail matrix. Only 18 cases of this tumor have been reported in the literature to date. We retrospectively analyzed the clinical features of 14 patients with OCM. The most common clinical feature was longitudinal xanthopachyonychia (n = 9), followed by longitudinal leukopachyonychia (=3) and longitudinal pachymelanonychia (n = 2). The most common clinical findings identified following dermoscopy and analysis at high magnification of classical photographs were free-edge thickening of the nail plate without pitting (n = 14), longitudinal ridging (n = 7), round white clods (n = 7), white dots (n = 7), and filiform hemorrhages (n = 7), followed by oval and linear white clods (n = 5), fuzzy lateral border (n = 5), and red-purple blood clods (n = 3). Nail clipping histopathology showed a thickened nail plate with multiple, small, round-to-oval spaces. The tumor expressed immunopositivity for LEF-1. Dermoscopy of the nail plate and nail clipping histology provides useful information with regards to the differential diagnosis with subungual squamous cell carcinoma and nail melanoma. Ex vivo-in vivo correlation facilitates a better dermoscopic assessment of this unique underrecognized disease. However, the differential diagnosis between OCM and onychocytic carcinoma requires biopsy of the tumor. LEF-1 as an onychogenic marker can be used to resolve the differential diagnosis between OCM and subungual longitudinal acanthoma/seborrheic keratosis.
Topics: Humans; Skin Neoplasms; Retrospective Studies; Nail Diseases; Acanthoma; Nails, Malformed; Carcinoma, Squamous Cell; Diagnosis, Differential; Dermoscopy
PubMed: 38513115
DOI: 10.1097/DAD.0000000000002674 -
Dermatopathology (Basel, Switzerland) Feb 2023Post-pemphigus acanthomas have been rarely discussed in the literature. A prior case series identified 47 cases of pemphigus vulgaris and 5 cases of pemphigus foliaceus,...
Post-pemphigus acanthomas have been rarely discussed in the literature. A prior case series identified 47 cases of pemphigus vulgaris and 5 cases of pemphigus foliaceus, out of which 13 developed acanthomata as a part of the healing process. Additionally, a case report by Ohashi et al. reported similar recalcitrant lesions on the trunk of a patient with pemphigus foliaceus being treated with prednisolone, IVIG, plasma exchange, and cyclosporine. Some view post-pemphigus acanthomas as variants of hypertrophic pemphigus vulgaris, being difficult to diagnose when they present as only single lesions, with a clinical differential of an inflamed seborrheic keratosis or squamous cell carcinoma. Here, we present a case of a 52-year-old female with a history of pemphigus vulgaris and four months of only topical therapy (fluocinonide 0.05%) who presented with a painful, hyperkeratotic plaque on the right mid-back that was found to be a post-pemphigus acanthoma.
PubMed: 36810570
DOI: 10.3390/dermatopathology10010012 -
Lin Chuang Er Bi Yan Hou Tou Jing Wai... Dec 2020The patient, a 70-year-old woman, presented with a mass in the right nasal cavity accompanied by recurrent nosebleeds for 3 months. Physical examination revealed a mass...
The patient, a 70-year-old woman, presented with a mass in the right nasal cavity accompanied by recurrent nosebleeds for 3 months. Physical examination revealed a mass in the right nasal vestibule, with a diameter of about 1.5 cm. The surface of the mass was not smooth and nasal CT showed a mass in the right nasal vestibule, which could be surgically removed. Immunohistochemical results of the tumor showed CKpan(3+), CK5/6(3+), p40(3+), p53(+), CD10(-), AR(-), Bcl-2(-), ki-67(+20%). Pathological diagnosis was acantholytic dyskeratotic acanthoma. This disease is rare and easy to be misdiagnosed, so it is necessary to pay attention to identification.
Topics: Acanthoma; Aged; Epistaxis; Female; Humans; Immunohistochemistry; Nasal Cavity; Nose Neoplasms; Skin Neoplasms
PubMed: 33254352
DOI: 10.13201/j.issn.2096-7993.2020.12.019 -
Anais Brasileiros de Dermatologia 2021
Topics: Acanthoma; Dermoscopy; Humans; Skin Neoplasms
PubMed: 34006397
DOI: 10.1016/j.abd.2020.06.027 -
Acta Dermato-venereologica Dec 2019
Review
Topics: Acanthoma; Administration, Topical; Adolescent; Biopsy, Needle; Combined Modality Therapy; Cryotherapy; Dermatologic Surgical Procedures; Diagnosis, Differential; Eczema; Female; Humans; Immunohistochemistry; Keratosis; Nipples; Pruritus; Rare Diseases; Skin Neoplasms; Treatment Outcome; Tretinoin
PubMed: 31580462
DOI: 10.2340/00015555-3328 -
Dermatopathology (Basel, Switzerland) Oct 2022Clear cell acanthoma (CCA) is classically considered a benign epidermal tumor, although rare case reports have described CCA with malignant features. Here, we present a...
Clear cell acanthoma (CCA) is classically considered a benign epidermal tumor, although rare case reports have described CCA with malignant features. Here, we present a case of a patient with a biopsy proven CCA that regrew post-biopsy and was subsequently completely excised. Histologic examination of the tumor in the excision specimen revealed malignant cytologic features that were not present in the initial biopsy. A review of the literature identified five additional cases of CCA with similar malignant cytologic features. On analysis, common histopathologic characteristics included cellular pleomorphism, increased nuclear-to-cytoplasmic ratio, prominent nucleoli, and atypical mitotic figures. We support the designation of atypical clear cell acanthoma for these entities with features of both CCA and significant cytologic atypia. As none of these cases exhibited clinically aggressive behavior, further study is warranted.
PubMed: 36278542
DOI: 10.3390/dermatopathology9040041 -
Dermatology Practical & Conceptual Jul 2021
PubMed: 34414014
DOI: 10.5826/dpc.1103a89 -
JAAD Case Reports Sep 2020
PubMed: 32885010
DOI: 10.1016/j.jdcr.2020.07.008