Cutaneous Horn Presentation in Porokeratotic Eccrine Ostial and Dermal Duct Nevus. A Brief Review and Case Report.

ABSTRACT: Porokeratotic eccrine ostial and dermal duct nevus is a rare adnexal hamartoma characterized by the presence of a cornoid lamella exclusively overlying eccrine acrosyringia. Different clinical presentations have been reported in the literature. Here, we report a case of a 6-year-old girl diagnosed with porokeratotic eccrine ostial and dermal duct nevus confirmed by histopathologic study. Atypical lesions are described as whitish, warty-looking neoformations located in the anterolateral region of the right hip (cutaneous horn).

Microsecretory adenocarcinoma of the skin, a novel type of sweat gland carcinoma: Report of three additional cases.

Microsecretory adenocarcinoma (MSA) is a newly described salivary gland tumor harboring a characteristic balanced chromosomal translocation resulting in MEF2C::SS18 gene fusion. Six primary cutaneous MSA cases have been recently described. We report three additional cases confirming the relevance of this recently identified entity of primary cutaneous adnexal tumor. Three patients aged 53-, 64- and 78-year-old were retrospectively diagnosed with MSA of the skin (MSAS) as consultation cases of the CARADERM (CAncers RAres DERMatologiques) national network. The clinical presentation was an indolent nodule on the upper extremities. There was no history of salivary gland tumor. Histopathologically, the tumors presented as dermal nodular proliferation with slightly infiltrative borders, composed of cribriform and microcystic structures with abundant myxoid intraluminal secretion embedded in a fibromyxoid stroma. They diffusely expressed cytokeratin 8 and SOX10, focally p63 and heterogeneously smooth muscle actin. All tumors harbored the MEF2C::SS18 gene fusion. A complete surgical excision was performed. No local recurrence or distant metastases were observed so far (follow-up: 17, 38, and 45 months). MSAS is the cutaneous homologue of MSA of the salivary gland, a low-grade adnexal neoplasm whose prognosis seems to be excellent once the complete removal of the tumor is assured.

Complex sweat gland hamartoma: A case report.

Syringocystadenoma papilliferum (SCAP), tubular apocrine adenoma (TAA), and eccrine nevus are rare benign sweat gland tumors with varied clinical presentations but generally distinctive histomorphologic profiles. TAA and SCAP have been associated with other cutaneous hamartomas, most commonly with nevus sebaceus. Additionally, TAA and SCAP have uncommonly co-occurred in the same lesion. In contrast to nevus sebaceus, eccrine nevus is considerably less common and is rarely associated with other benign adnexal lesions. Here we present an unusual case of a complex sweat gland hamartoma containing features of syringocystadenoma papilliferum, tubular apocrine adenoma, and eccrine nevus in a 7-year-old female.

Radiation-Induced Eccrine Squamous Syringometaplasia With Perineural Invasion.

ABSTRACT: Eccrine squamous syringometaplasia (ESS) is a benign metaplastic reaction of eccrine ducts that occurs in response to injury and can be a histologic mimic of squamous cell carcinoma (SCC). Reported is an 82-year-old man undergoing Mohs surgery for presumed SCC diagnosed in a field of radiation dermatitis. After 3 Mohs stages, the peculiar squamous proliferation was recognized as ESS and the procedure was aborted. Complicating the interpretation of the Mohs frozen section was the presence of perineural invasion because perineural invasion has not been previously reported to occur with ESS. The histologic features used to distinguish ESS from SCC are discussed.

Type 1 interferon signature and cytotoxic T lymphocyte activation targeted against sweat ducts in inflammatory acquired idiopathic generalized anhidrosis.

BACKGROUND: Acquired idiopathic generalized anhidrosis (AIGA) leads to heat intolerance due to the loss or reduction in thermoregulatory sweating over an extensive area of the body. The pathomechanism of AIGA is still unclear but is believed to be autoimmune. OBJECTIVES: We investigated the clinical and pathological features of inflammatory AIGA (InfAIGA) and noninflammatory AIGA (non-InfAIGA) within the skin. METHODS: We compared anhidrotic and normohidrotic skin samples from 30 patients with InfAIGA and non-InfAIGA, as well as skin samples of melanocytic nevus as a negative control. We conducted morphometric analysis and immunohistochemical analysis of cell types and expression of inflammatory molecules (TIA1, CXCR3 and MxA). MxA expression was used as a proxy for type 1 interferon activity. RESULTS: We found that tissue samples from patients with InfAIGA exhibited inflammation within the sweat duct and atrophy of the sweat coil, whereas patients with non-InfAIGA exhibited only atrophy of the sweat coil. Cytotoxic T lymphocyte infiltration and MxA expression were only observed in the sweat ducts of patients with InfAIGA. CONCLUSIONS: InfAIGA is associated with increased sweat duct inflammation and sweat coil atrophy, whereas non-InfAIGA is only associated with sweat coil atrophy. These data suggest that inflammation leads to epithelial destruction of sweat ducts associated with the sweat coil atrophy and subsequent loss of function. Non-InfAIGA may be regarded as a postinflammatory state of InfAIGA. These observations indicate the contribution of both type 1 and type 2 interferons to sweat gland injury. The mechanism involved is similar to the pathomechanism of alopecia areata (AA).

Next-generation sequencing analysis suggests varied multistep mutational pathogenesis for endocrine mucin-producing sweat gland carcinoma with comments on INSM1 and MUC2 suggesting a conjunctival origin.

Endocrine mucin-producing sweat gland carcinoma is a low-grade eyelid tumor. Small biopsies and insensitive immunohistochemistry predispose to misdiagnosis. We aimed to identify clarifying immunohistochemical markers, molecular markers, or both. Clinicopathologic data (22 cases) were reviewed. Immunohistochemistry (insulinoma-associated protein 1, BCL-2, mucin 2 [MUC2], mucin 4, androgen receptor, ß-catenin, and Merkel cell polyomavirus) and next-generation sequencing (Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets, 468 genes) were performed (3 cases). Female patients (n = 15) and male patients (n = 7) (mean age 71.8 years; range 53-88 years) had eyelid or periorbital tumors (>90%) with mucin-containing solid or cystic neuroendocrine pathology. Immunohistochemistry (insulinoma-associated protein 1, BCL2, androgen receptor, retinoblastoma-associated protein 1, and ß-catenin) was diffusely positive (5/5), MUC2 partial, mucin 4 focal, and Merkel cell polyomavirus negative. Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets identified 12 single-nucleotide variants and 1 in-frame deletion in 3 cases, each with DNA damage response or repair (BRD4, PPP4R2, and RTEL1) and tumor-suppressor pathway (BRD4, TP53, TSC1, and LATS2) mutations. Microsatellite instability, copy number alterations, and structural alterations were absent. Insulinoma-associated protein 1 and MUC2 are positive in endocrine mucin-producing sweat gland carcinoma. MUC2 positivity suggests conjunctival origin. Multistep pathogenesis involving DNA damage repair and tumor-suppressor pathways may be implicated.

Endocrine Mucin-Producing Sweat Gland Carcinoma: Emerging Evidence of Multicentric Cutaneous Origin and Occasional Concurrence With Analogous Breast Tumors.

INTRODUCTION: Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a low-grade carcinoma with predilection for the eyelid. It is analogous to solid papillary carcinoma of the breast with both expressing neuroendocrine markers and the potential to progress to invasive mucinous carcinoma (IMC). Although over 80 cases of EMPSGC have been reported, few multicentric cases have been described in the literature. In this article, we report 9 cases of EMPSGC including 3 with multicentric disease. METHODS: A computerized search was performed for EMPSGC and IMC of the eyelid from January 2000 to February 2021. Records were reviewed for age, sex, tumor location, and clinical impression. RESULTS: Eight EMPSGC (7 associated with IMC) and 1 IMC of the eyelid were identified. Lesions were slightly more common in men (55%) than women. The mean age of presentation was 76 years (range, 59-98 years). Lesions ranged from 2.5 to 12 mm. Three cases had multicentric synchronous lesions on the skin. Histologically, these were well-circumscribed dermal tumors with solid or partially cystic nodules. Tested tumors expressed at least 1 neuroendocrine marker and were positive for CK7, ER/PR, 1 or more of GCDFP-15, mammaglobin, and GATA-3. One case had an associated IMC of the breast, and another case was associated with an intraductal papilloma of the breast in a man. There was no evidence of metastasis. CONCLUSION: EMPSGC is a low-grade adnexal neoplasm, commonly affecting the eyelid of the elderly. Lesions often progress to IMC, metastases being exceptionally rare. EMPSGC can be bilateral and multicentric. Concurrence with breast neoplasms has been observed and deserves investigation.

Sweat Gland Carcinoma With Neuroendocrine Differentiation of the Areola as a Potential Clinicopathologic Mimicker of Male Breast Carcinoma and Syringocystadenocarcinoma Papilliferum.

ABSTRACT: Sweat gland carcinoma with neuroendocrine differentiation (SCAND) is a newly proposed tumor entity of primary cutaneous apocrine/eccrine adnexal tumor with neuroendocrine differentiation. The histopathologic variations are not yet well known. In this article, we present a case of SCAND mimicking male breast cancer and syringocystadenocarcinoma papilliferum. A 68-year-old man presented with a reddish 12-mm nodule on his left areola. No lymph node or distant metastases were observed. The patient was disease free 1 year and 9 months after the tumor was surgically resected but died of cerebral hemorrhage. Histopathological examination revealed a predominantly intradermal tumor with marked syringotropism, mimicking a component of mammary ductal carcinoma in situ. In addition, another tissue section displayed a cup-shaped papillated tumor with syringocystadenocarcinoma papilliferum-like features, which were also seen because of marked syringotropism. Diffuse immunoexpression of cytokeratin 7, cytokeratin 19, chromogranin A, synaptophysin, INSM1, estrogen receptor, carcinoembryonic antigen, epithelial membrane antigen, and GATA3 was observed in the tumor, but no BRAF immunoexpression was seen. The present case would help us to understand the histopathological variation and differential diagnosis of SCAND. The histopathological diagnosis of male breast cancer or syringocystadenocarcinoma papilliferum should be made by ruling out SCAND.

Syringotropic Melanoma: A Diagnostic Challenge With Prognostic Implications.

ABSTRACT: The presence of neoplastic melanocytes within the eccrine apparatus into the reticular dermis and/or subcutaneous tissue is extremely rare. The staging of syringotropic melanomas and their biological behavior are still controversial. We present 6 new cases of syringotropic melanoma and their main histopathologic features; review the previous literature; and discuss about the origin, staging, and prognosis of this rare variant of melanoma.

Axillary masses as clinical manifestations of male sweat gland carcinoma associated with extramammary Paget's disease and accessory breast carcinoma: two cases report and literature review.

BACKGROUND: Male cases of accessory breast carcinoma and sweat gland carcinoma associated with extramammary Paget's disease of the axilla are uncommon. In clinical diagnosis and treatment, it is necessary to determine the disease carefully and make a reasonable treatment strategy according to the patient's situation. CASE PRESENTATION: We described two male cases of the special tumor with an axillary mass as the first clinical symptom, one of which was diagnosed as accessory breast cancer and the other as sweat gland cancer associated with extramammary Paget's disease. We treated the two diseases individually in the hopes of providing a reference for the diagnosis and management of diseases with axillary nodules as the initial symptom. CONCLUSIONS: The reports of these two cases can provide reference and corresponding thinking for clinical differentiation of axillary lymphadenopathy caused by different causes and subsequent treatment. These two cases may further enrich the database of rare cases and provide some ideas for the treatment of axillary lymphadenopathy caused by different causes.

Bilateral Concurrent Endocrine Mucin-Producing Sweat Gland Carcinoma and Mucinous Carcinoma of the Eyelids.

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is thought to be a precursor to mucinous carcinoma, both of which are rare. In this case report, the authors present a 55-year-old woman with concurrent EMPSGC and mucinous carcinoma manifesting with 2 distinct lesions on her left upper and lower eyelid and 1 lesion on her right lower eyelid. Biopsy and immunohistochemical staining supported primary cutaneous origin of the tumors. Systemic metastatic workup was initiated and thus far negative. The patient underwent staged slow Mohs micrographic surgery to remove one tumor at a time, with delayed reconstruction. This is the first reported case of EMPSGC and mucinous carcinoma presenting as distinct lesions both bilaterally and synchronously.

Simultaneous presentation of orbital mantle cell lymphoma and endocrine mucin-producing sweat gland carcinoma.

Mantle cell lymphoma is a rare malignancy to present in the orbit, comprising only 1-5% adnexal lymphomas. Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is an equally uncommon adnexal tumor of sweat gland origin that may present on the eyelid. Herein we present a case of a 77-year old man with no previous cancer history who presented with painless progressive left globe proptosis and an enlarging left upper lid margin lesion, ultimately determined upon biopsy to be simultaneous orbital mantle cell lymphoma with systemic involvement and isolated eyelid EMPSGC. The pathogenesis, clinical manifestation, and management for each rare disease entity are reviewed and concept of collision tumors is discussed.

Secretory carcinoma of the skin with lymph node metastases and recurrence in both lungs: A case report.

Secretory carcinoma of the skin is an extremely rare adnexal tumor, histopathologically identical to homologous lesions in the salivary glands and breast tissue. Although this tumor was previously reported as indolent, we report a case of secretory carcinoma of the skin with metastases and recurrence. The patient, a 31-year-old women, had a subcutaneous mass in the right axilla. The resected specimen contained a circumscribed mass, with proliferating tumor cells that exhibited prominent nucleoli. They exhibited glandular and papillary growth patterns and there were amphophilic secretions in the glands. Immunohistochemically, the tumor cells were positive for mammaglobin and S100. The tumor was surrounded by sweat glands and there was no mammary glandular tissue, suggesting that it was derived from axillary sweat glands. Accordingly, we made a diagnosis of secretory carcinoma of the skin. Four years after the operation, there were metastases in both lungs. The resected specimen revealed a tumor identical to that of the original skin tumor. Next-generation sequencing-based multiplex gene assay performed on the metastatic tissue revealed an ETV6-NTRK3 fusion gene. This is a rare case report of secretory carcinoma of the skin with lymph node metastases and recurrence in both lungs.

Trichilemmal Cysts With Divergent Ductal Differentiation: A Series of 4 Cases.

ABSTRACT: Trichilemmal cysts are common clonal tumors with a predilection for the scalp. They are composed of an outer epithelial wall resembling the outer root sheath in the isthmus of the hair follicle and a central core of compact keratin. Sweat duct differentiation is exceptional with only one convincing case reported to date. Here, we sought to characterize the clinicopathological characteristics of sweat duct differentiation in trichilemmal cysts. We reviewed all cases of trichilemmal cyst diagnosed at our institution between 2008 and 2019. Ductal structures were found in 4 of 411 cases (0.97%). Subjects included 2 male and 2 female patients with a median age of 37.5 years (range 34-55). The ducts were lined by attenuated epithelial cells and immunoreactive for polyclonal carcinoembryonic antigen and cytokeratin 7. Ductal differentiation involved a median of 7.5% (range 1%-50%) of the cyst wall. All 4 cases were from the scalp and treated with local excision. No recurrence was identified with a median follow-up period of 1.5 years (range 1-12 years). In summary, sweat duct differentiation in trichilemmal cysts is rare but likely under recognized. Conceptually, we suggest it represents a type of divergent cellular differentiation within a clonal neoplasm rather than a retention cyst or hybrid cyst.

Histopathological Differentiation of Antemortem and Postmortem Electrical Burn Mark Produced by Low Voltage.

ABSTRACT: The study was undertaken to differentiate antemortem electrical (AME) and postmortem electrical (PME) burn marks with the help of histopathology. The electrical burn mark was produced on 25 dead bodies. Alongside 25 cases of electrocution deaths were included for comparison. Slides were prepared and stained with hematoxylin-eosin stains. Intraepidermal and subepidermal separation; coagulative necrosis of the epidermis; nuclear elongation and hyperchromasia of epidermal cells; homogenization of the dermis; nuclear elongation and hyperchromasia of hair follicles, sweat glands, sebaceous glands, and blood vessel endothelium were studied for histopathological changes and graded. The findings of the study suggest that the histopathological changes in electrical burn marks are due to the physical effect of heat produced by the electric current. The classical histopathological features of electrical burn mark cannot differentiate between AME and PME burn marks. However, careful evaluation of grading of the dermal changes can be helpful in differentiating AME and PME burn marks. Highest grade of dermal thickness homogenization and highest grade of nuclear elongation of dermal appendages were significantly more in the antemortem electrical burn marks than PME burn marks.

Involvement of activin a receptor type 1 (ACVR1) in the pathogenesis of primary focal hyperhidrosis.

The pathogenesis of primary focal hyperhidrosis (PFH) is still not clear. PFH is thought to be a genetic disease. Whether activin A receptor type 1 (ACVR1) is involved in the pathogenesis of PFH is unknown. In this study, the expression of ACVR1 in sweat glands of patients with PAH was detected by western blot and immunofluorescence. The primary sweat gland cells obtained from primary axillary hyperhidrosis (PAH) patients were transfected with acvr1 vector. Cell proliferation, apoptosis and cell cycling of gland cells were measured after transfection with acvr1 vector. The mRNA and protein expression of aquaporin 5 (AQP5) and Na:K:2Cl Cotransporter 1 (NKCC1/SLC12A2) were detected. Our data showed that ACVR1 expression in axillary sweat gland tissue of PAH patients was significantly higher than that of normal control group. The function of ACVR1 was further investigated in the gland cells obtained from PAH patients. Compared with NC group, ACVR1 overexpression significantly promoted the proliferation of sweat gland cells and inhibited the apoptosis of sweat gland cells. Meanwhile, ACVR1 overexpression significantly reduced the percentage of cells in G0/G1 and G2/M phases, and increased the percentage of cells in S phase. In addition, ACVR1 overexpression significantly promoted the expression of AQP5 and NKCC1 at both mRNA and protein levels. Together, ACVR1 expression is related to PFH and ACVR1 overexpression can promote the proliferation of sweat gland cells and inhibit apoptosis by promoting the expression of AQP5 and NKCC1.

Diagnostic utility of small fiber analysis in skin biopsies from children with chronic pain.

INTRODUCTION: Small fiber neuropathies (SFN) are associated with a reduction in quality of life. In adults, epidermal nerve fiber density (END) analysis is recommended for the diagnosis of SFN. In children, END assessment is not often performed. We analyzed small nerve fiber innervation to elucidate the potential diagnostic role of skin biopsies in young patients with pain. METHODS: Epidermal nerve fiber density and sudomotor neurite density (SND) were assessed in skin biopsies from 26 patients aged 7 to 20 years (15 female patients) with unexplained chronic pain. The results were compared with clinical data. RESULTS: Epidermal nerve fiber density was abnormal in 50% and borderline in 35% of patients. An underlying medical condition was found in 42% of patients, including metabolic, autoimmune, and genetic disorders. DISCUSSION: Reduction of epidermal nerve fibers can be associated with treatable conditions. Therefore, the analysis of END in children with pain may help to uncover a possible cause and guide potential treatment options.

Eccrine duct dilatation in neutrophilic scarring alopecias.

BACKGROUND: Eccrine duct dilatation (EDD) has been noted to occur significantly more often in primary lymphocytic scarring alopecias compared with non-scarring alopecias, thus serving as a possible histopathologic marker for primary scarring alopecias with a lymphocytic infiltrate. This study aims to determine the presence and role of EDD in primary neutrophilic scarring alopecias. METHODS: We performed a retrospective review comparing primary scarring alopecia (neutrophilic, n = 90; lymphocytic, n = 100) and non-scarring alopecia (n = 123) for presence of EDD, seen in Boston University School of Medicine between 2013 and 2017. RESULTS: EDD was more commonly seen in primary neutrophilic scarring (62.2%, 56/90) and primary lymphocytic scarring alopecias (54.0%, 54/100) than in non-scarring alopecias (25.2%, 31/123) (P < 0.001). Albeit uncommon, non-scarring alopecias exhibited the biggest ratio of dilated eccrine duct lumen to background duct lumen (14.33), followed by lymphocytic (10.99) and neutrophilic scarring alopecias (6.66). CONCLUSION: EDD is seen more frequently in primary scarring alopecias compared with non-scarring alopecias and usually found in sections containing inflammation and dermal fibrosis, serving as a possible histopathologic clue for a scarring process. Non-scarring alopecias have significantly fewer but considerably larger EDD which, may imply a different pathologic cause.

Primary cutaneous solitary fibrous tumor with entrapped eccrine components.

First described in the pleura, solitary fibrous tumor (SFT) was subsequently reported in a variety of organ systems. Compared to other anatomic sites, primary cutaneous and superficial SFTs are relatively rare. Although several histopathologic variants of cutaneous and superficial SFT have been described, a primary cutaneous SFT harboring glandular components has not hitherto been documented in the literature. The current case report describes a spindle cell neoplasm of the right finger in a female patient with characteristic morphologic and immunohistochemical features of a SFT. Unexpectedly, various glandular and ductal components were identified in the SFT. A few hyperplastic lobules of sweat glands demonstrating similar morphology as the intratumoral glandular components and composed of secretory coils displaying mucinous metaplasia and ducts were detected in the attached subcutaneous tissue, suggestive of an inductive or obstructive effect of the SFT on the eccrine units. The intratumoral glands and ducts were judged to represent entrapped benign eccrine components from the attached subcutaneous tissue. Since this variant of SFT with entrapped eccrine components could mimic many biphasic epithelial and stromal tumors, pathologists should be aware of this unusual variant of SFT to avoid potential erroneous diagnosis, particularly mistaken confusion with a biphasic synovial sarcoma.

Gene expression profiling in aggressive digital papillary adenocarcinoma sheds light on the architecture of a rare sweat gland carcinoma.

BACKGROUND: Sweat gland carcinomas are rare cutaneous adnexal malignancies. Aggressive digital papillary adenocarcinoma (ADPA) represents a very rare subentity, thought to arise almost exclusively from the sweat glands of the fingers and toes. The aetiology of sweat gland carcinomas and ADPA is largely unknown. ADPAs are most likely driven by somatic mutations. However, somatic mutation patterns are largely unexplored, creating barriers to the development of effective therapeutic approaches to the treatment of ADPA. OBJECTIVES: To investigate the transcriptome profile of ADPA using a sample of eight formalin-fixed, paraffin-embedded tissue samples of ADPA and healthy control tissue. METHODS: Transcriptome profiling was performed using the Affymetrix PrimeView Human Gene Expression Microarray and findings were validated via reverse transcription of RNA and real-time quantitative polymerase chain reaction. RESULTS: Transcriptome analyses showed increased tumour expression of 2266 genes, with significant involvement of cell cycle, ribosomal and crucial cancer pathways. Our results point to tumour overexpression of FGFR2 (P = 0·001). CONCLUSIONS: The results indicate the involvement of crucial oncogenic driver pathways, highlighting cell cycle and ribosomal pathways in the aetiology of ADPA. Suggested tumour overexpression of FGFR2 raises the hope that targeting the fibroblast growth factor (FGF)/FGF receptor axis might be a promising treatment for ADPA and probably for the overall group of sweat gland carcinomas.