Gene fusions in poroma, porocarcinoma and related adnexal skin tumours: An update.

Poroma is a benign sweat gland tumour showing morphological features recapitulating the superficial portion of the eccrine sweat coil. A subset of poromas may transform into porocarcinoma, its malignant counterpart. Poroma and porocarcinoma are characterised by recurrent gene fusions involving YAP1, a transcriptional co-activator, which is controlled by the Hippo signalling pathway.

Loss of YAP1 C-terminus expression as an ancillary marker for metaplastic thymoma: a potential pitfall in detecting YAP1::MAML2 gene rearrangement.

Aims: Metaplastic thymoma is a rare thymic tumour characterized by Yes Associated Protein 1 (YAP1) and Mastermind Like Transcriptional Coactivator 2 (MAML2) gene fusions resulting from an intrachromosomal inversion of chromosome 11. Immunohistochemistry with an antibody directed against the C-terminus of YAP1 has shown loss of expression in YAP1-rearranged vascular neoplasms, poromas, and porocarcinomas. This study aimed to validate an anti-YAP1 C-terminal antibody as an ancillary immunohistochemical marker for the diagnosis of metaplastic thymoma.

Generalized Reddish Skin Nodules.

Diagnosis of nodular red lesions is challenging. The differential diagnosis includes dermal nevus, angioma, pyogenic granuloma, amelanotic melanoma, eccrine poroma, Kaposi's sarcoma, skin malignancy or metastasis. Erythema nodosum is one of the common consideration of the red skin nodules, however fully work up should be done to find the right diagnosis.

Poroma in a Patient With Fitzpatrick Type V Skin.

This case detailing a poroma in Fitzpatrick Type V skin presents gross, dermatoscopic, and histopathologic images that have not been adequately represented in the literature. Diagnosing poroma can be challenging and misdiagnoses can have tragic consequences. The scarcity of published poroma images in darker skin types can further complicate this problem.

Cuticular Poroma: A Rare Poroma Variant Simulating a Malignant Neoplasm That Often Harbors YAP1::NUTM1 Fusions Similar to Their Conventional Counterparts.

Cuticular poroma is a rare variant of poroma composed of exclusively or predominantly cuticular cells, namely of large cells with ample eosinophilic cytoplasm. We report 7 cases of this rare tumor identified among 426 neoplasms diagnosed as poroma or porocarcinoma. The patients were 4 males and 3 females, ranging in age from 18 to 88 years.

Combined tumour of aberrant cytokeratin expressing acral lentiginous melanoma and poroma: Diagnostic challenge.

Combined tumours are uncommon and therefore these tumours may pose a diagnostic challenge. In the current case report, it is aimed to present the clinicopathological features of a combined tumour including melanoma with aberrant cytokeratin expression and poroma.

Recurrent PAK2 rearrangements in poroma with folliculo-sebaceous differentiation.

Aims: Poroma is a benign adnexal neoplasm with differentiation towards the upper portion of the sweat gland apparatus. In 2019, Sekine et al. demonstrated recurrent YAP1::MAML2 and YAP1::NUTM1 fusion in poroma and porocarcinoma.

Eccrine Porocarcinoma: A Review of the Literature.

Eccrine porocarcinoma (EPC) constitutes a rare malignant adnexal tumor, which accounts for about 0.005-0.01% of all cutaneous malignancies.

18F Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Findings in a Case of Metastatic Eccrine Porocarcinoma - An Extremely Rare Malignant Adnexal Tumor.

Porocarcinoma is a rare malignant neoplasm of eccrine sweat glands representing 0.005 to 0.1% of all cutaneous tumors.

The role of line-field confocal optical coherence tomography (LC-OCT) in the diagnosis of eccrine poroma: A case report.

Poroma is skin cancer that arises from the sweat gland cells. Its diagnosis could be difficult. Line-field optical coherence tomography (LC-OCT) is a novel imaging technique that has shown promise in the diagnosis and monitoring of various skin conditions.

Wide Local Excision for Eccrine Porocarcinoma of the Forearm.

Eccrine porocarcinoma is a rare and aggressive cutaneous malignancy that develops in the seventh and eight decades of life. We present a 76-year-old male with eccrine porocarcinoma developing from a long standing previously benign lesion who underwent successful treatment with wide local excision. It can also develop de novo, presenting most commonly as a mass or nodule.

Cryotherapy for Eccrine Poroma: A Case Report.

Eccrine poroma (EP) is a benign adnexal tumor that is derived from acrosyringium, the intraepidermal eccrine duct of sweat glands. The standard treatment for eccrine poroma is complete excision. However, this case report highlights cryotherapy as one of the modalities in treating eccrine poroma.

Clinicopathological Spectrum of Benign Skin Adnexal Tumors in the Pakistani Population: A Single-Center Study.

Background Skin adnexal tumors (SATs) are categorized per the site of origin, for example, hair follicles, sebaceous glands, and sweat glands. In our population, there is limited information related to the clinicopathological characteristics of these tumors. Management and prognosis depend largely upon the morphological type of the tumor.

Eccrine Poroma: A Case Report.

Eccrine poroma is a benign adnexal neoplasm often mistaken for pyogenic granuloma, skin tag, squamous cell carcinoma, and other soft-tissue tumors. We describe a 69-year-old woman with a soft-tissue mass on the lateral aspect of her right hallux that was initially clinically diagnosed as a pyogenic granuloma. Histologic examination proved that this mass was instead an eccrine poroma, the rare benign sweat gland tumor.

TRPS1 Is Differentially Expressed in a Variety of Malignant and Benign Cutaneous Sweat Gland Neoplasms.

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 a spectrum of cutaneous sweat gland tumors.

YAP1::MAML2 fusions in poromatosis: A report of two patients.

Poromatosis is a rare condition characterized by the development of multiple poromas, mainly reported in patients with a history of malignancy. Recently, frequent YAP1::MAML2 and YAP1::NUTM1 fusions have been described in poromas and porocarcinomas. To date, the molecular features of poromatosis have been investigated in one patient only, wherein the poromas harbored YAP1::MAML2 fusions.

Distinct regulations driving YAP1 expression loss in poroma, porocarcinoma and RB1-deficient skin carcinoma.

Aims: Recently, YAP1 fusion genes have been demonstrated in eccrine poroma and porocarcinoma, and the diagnostic use of YAP1 immunohistochemistry has been highlighted in this setting. In other organs, loss of YAP1 expression can reflect YAP1 rearrangement or transcriptional repression, notably through RB1 inactivation. In this context, our objective was to re-evaluate the performance of YAP1 immunohistochemistry for the diagnosis of poroma and porocarcinoma.

Reactive Eccrine Syringofibroadenoma (ESFA) in Association With a Merkel Cell Carcinoma Excision Scar.

Eccrine syringofibroadenoma (ESFA) is a rare benign skin adnexal lesion of the acrosyringium of eccrine sweat ducts. Reactive ESFA, a subtype of ESFA, is usually associated with non-neoplastic cutaneous dermatoses or neoplastic skin tumors. Clinically, the lesions can be solitary or multiple, pink, or skin-colored coalescing papules or nodules of variable sizes.

An Unusual Case of a Scrotal Porocarcinoma and Review of the Literature.

Porocarcinomas are rare tumors derived from the acrosyringium and eccrine ducts, which most commonly occur on the lower extremities or head and neck region in older adults. Microscopically, they invariably demonstrate continuity with the epithelium, showing downgrowth of broad anastomosing bands with more infiltrative intradermal cords and nests of pleomorphic tumor cells with ductal lumina; an associated poroma may also be seen. We report an unusual case of a porocarcinoma arising on the scrotum of a 55-year-old man.

Dermoscopy for the Identification of Amelanotic Acral Melanoma.

Acral lentiginous melanoma is commonly misdiagnosed, and when detected late it portends a poor prognosis. Acral lentiginous melanoma can be mistaken for verruca, pyogenic granuloma, poroma, an ulcer, or other benign skin conditions. Patients with acral skin growths often present initially to a podiatric physician or their primary care physician.