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International Journal of Surgery Case... Feb 2024Lipomatous neoplasms of the parotid gland represent an exceptionally rare and often underdiagnosed category of tumors, accounting for an incidence ranging from 0.6 % to...
INTRODUCTION AND IMPORTANCE
Lipomatous neoplasms of the parotid gland represent an exceptionally rare and often underdiagnosed category of tumors, accounting for an incidence ranging from 0.6 % to 4.4 % of all neoplasms detected within the parotid gland. Sialolipoma is defined as an uncommon variant of lipoma, characterized by a well-defined proliferation of mature adipocytes with secondary entrapment of salivary gland elements, including serous acini, ducts, and myoepithelial cells.
CASE PRESENTATION
The current case pertains to a 17-year-old female who presented with a one-year history of enlargement in the left preauricular region.
CLINICAL DISCUSSION
The case we present poses a complex diagnostic challenge due to two distinct characteristics. The diagnostic challenge lies in its remarkably low incidence and the propensity for confusion with pleomorphic adenoma, which is the most common tumor of the parotid gland. It is a benign disease entity characterized by the absence of dysplasia, in marked contrast to pleomorphic adenoma.
CONCLUSIONS
The infrequency in the manifestation of these tumor types, coupled with their prolonged asymptomatic course, can pose a diagnostic challenge. Enhancing our knowledge to comprehensively delineate these entities is imperative to effectively address the diagnostic complexities from both clinical and histopathological standpoints.
PubMed: 38227981
DOI: 10.1016/j.ijscr.2024.109264 -
Diagnostic Cytopathology Apr 2024Spindle cell lipoma (SCL) is a rare form of lipoma, typically occurring as a mass in the back, shoulder or posterior neck of adult males. Most cases present little...
Spindle cell lipoma (SCL) is a rare form of lipoma, typically occurring as a mass in the back, shoulder or posterior neck of adult males. Most cases present little diagnostic difficulty on fine needle aspiration (FNA), but can be problematic when the SCL is in an unusual location. The authors report a case in the parotid gland in a 75-year-old man. FNA was paucicellular and showed loose collections of spindle cells with mild to moderate atypia, admixed with ropy collagen fibers on a myxoid background. The nuclei showed occasional angulation, interpreted on FNA as suspicious for myoepithelial tumor or low-grade sarcoma. The subsequent excisional specimen was diagnosed as SCL. On retrospective review of the FNA, an additional finding was recognized: 'naked' nuclei with intranuclear lipid vacuoles and positive immunostaining for S100 protein, consistent with Lochkern cells of mature adipocytes. This case highlights the challenges of diagnosing SCL on cytology when no fat-containing cells are apparent on the smear, and stresses the significance of Lochkern cells as a clue for diagnosis.
Topics: Aged; Humans; Male; Adipocytes; Biopsy, Fine-Needle; Cell Nucleus; Lipoma; Parotid Gland
PubMed: 38217263
DOI: 10.1002/dc.25271 -
Scientific Reports Jan 2024Salivary gland myoepithelial cells regulate saliva secretion and have been implicated in the histological diversity of salivary gland tumors. However, detailed...
Salivary gland myoepithelial cells regulate saliva secretion and have been implicated in the histological diversity of salivary gland tumors. However, detailed functional analysis of myoepithelial cells has not been determined owing to the few of the specific marker to isolate them. We isolated myoepithelial cells from the submandibular glands of adult mice using the epithelial marker EpCAM and the cell adhesion molecule CD49f as indicators and found predominant expression of the transcription factor FoxO1 in these cells. RNA-sequence analysis revealed that the expression of cell cycle regulators was negatively regulated in FoxO1-overexpressing cells. Chromatin immunoprecipitation analysis showed that FoxO1 bound to the p21/p27 promoter DNA, indicating that FoxO1 suppresses cell proliferation through these factors. In addition, FoxO1 induced the expression of ectodysplasin A (Eda) and its receptor Eda2r, which are known to be associated with X-linked hypohidrotic ectodermal dysplasia and are involved in salivary gland development in myoepithelial cells. FoxO1 inhibitors suppressed Eda/Eda2r expression and salivary gland development in primordial organ cultures after mesenchymal removal. Although mesenchymal cells are considered a source of Eda, myoepithelial cells might be one of the resources of Eda. These results suggest that FoxO1 regulates myoepithelial cell proliferation and Eda secretion during salivary gland development in myoepithelial cells.
Topics: Animals; Mice; Ectodysplasins; Epithelial Cells; Receptors, Tumor Necrosis Factor; Salivary Gland Neoplasms; Submandibular Gland; Transcription Factors; Xedar Receptor
PubMed: 38212454
DOI: 10.1038/s41598-024-51619-1 -
Cureus Dec 2023Metaplastic breast carcinoma represents a diverse category of invasive breast cancers distinguished by the transformation of neoplastic epithelial cells into squamous...
Metaplastic breast carcinoma represents a diverse category of invasive breast cancers distinguished by the transformation of neoplastic epithelial cells into squamous cells or cells with mesenchymal appearance. Matrix-producing breast carcinoma is a variant of metaplastic breast carcinoma, an exceedingly uncommon malignancy accounting for less than 1% of all breast tumors. The precise origin of this tumor remains elusive; some molecular research points to a potential derivation from myoepithelial cells, while other studies emphasize the possibility of neoplastic transformation originating from multipotent stem cells. We report a case of recurrent matrix-producing breast carcinoma. The patient presented with a breast mass. The tumor cells displayed a lack of reactivity for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2), and exhibited a Ki-67 proliferation index of approximately 40%. Additionally, the tumor cells demonstrated significant reactivity for cytokeratins and S100. The patient underwent surgery, radiation, and chemotherapy and then developed metastasis to the lower lobe of her left lung, seven years after primary diagnosis. Diagnosis of metastasis was confirmed by comparing the metastasis to the primary tumor and staining with a panel of immunohistochemical stains. The patient is currently undergoing chemotherapy and immunotherapy.
PubMed: 38196420
DOI: 10.7759/cureus.50265 -
Oral Surgery, Oral Medicine, Oral... Nov 2023Salivary gland and odontogenic neoplasms with extensive clear cell change are rare lesions but have been increasingly characterized over the past decade. Among this...
Salivary gland and odontogenic neoplasms with extensive clear cell change are rare lesions but have been increasingly characterized over the past decade. Among this heterogeneous group of neoplasms, hyalinizing clear cell carcinoma (HCCC), clear cell odontogenic carcinoma (CCOC), and clear cell myoepithelial carcinoma (CCMC) share a monophasic clear cell morphology and an EWSR1 gene rearrangement. While HCCC is relatively well characterized, there are a limited number of EWSR1-reaarranged CCMC of salivary glands reported, and its clinicopathologic features in relation to HCCC and nonclear cell myoepithelial carcinoma (MC) have not been clarified. This report describes the clinical, morphologic, and immunophenotypic features of 3 carcinomas composed predominantly of clear cells and with EWSR1 rearrangements by fluorescence in situ hybridization. A comparative literature analysis suggests that HCCC, CCMC, and nonclear cell MC of salivary glands are clinically, histopathologically, and molecularly distinct.
PubMed: 38155013
DOI: 10.1016/j.oooo.2023.11.010 -
Journal of Breast Imaging Jan 2024Adenomyoepithelioma (AME) is a rare, usually benign breast neoplasm with low potential for malignant transformation. Imaging features are nonspecific and overlap with...
Adenomyoepithelioma (AME) is a rare, usually benign breast neoplasm with low potential for malignant transformation. Imaging features are nonspecific and overlap with other benign and malignant breast lesions. On mammography, AME most often presents as a mass, usually oval in shape, with variable reported margins. Less commonly, AME can present mammographically as an asymmetry or can be mammographically occult. Associated calcifications are uncommon. On US, AME is usually seen as a hypoechoic oval mass, but it can also manifest as a complex cystic and solid mass. On US, the majority of AME have noncircumscribed margins (indistinct, angular, or microlobulated). Internal vascularity is usually present, and posterior enhancement can be seen. Although there is limited literature on MRI features, the most frequent finding is an irregular mass with washout kinetics; T2 hyperintensity can be observed. These nonspecific and often suspicious imaging features usually merit biopsy. On histologic analysis, AME is characterized by a biphasic proliferation of myoepithelial and epithelial cells. Pathologic diagnosis can be difficult due to the variety of histologic features of AME and heterogeneity in these tumors, especially when sampling is limited, such as in core needle biopsies. Wide local surgical excision of AME is recommended due to potential for recurrence and malignant transformation.
Topics: Humans; Female; Adenomyoepithelioma; Breast; Breast Neoplasms; Mammography; Biopsy
PubMed: 38153758
DOI: 10.1093/jbi/wbad098 -
The Ocular Surface Jan 2024Myoepithelial cells (MECs) are a unique subset of epithelial cells that possess several smooth muscle cell characteristics, such as a high number of actin-myosin... (Review)
Review
Myoepithelial cells (MECs) are a unique subset of epithelial cells that possess several smooth muscle cell characteristics, such as a high number of actin-myosin filaments and the ability to contract. These cells are primarily located around the secretory cells of exocrine glands, including the salivary, mammary, lacrimal, and sweat glands. Their primary functions involve the construction of the basement membrane and help with secretion of gland products through contraction. So far, no comparative analysis of MECs in different exocrine glands had ever evaluated their differences. In this review, we took advantage of the various publicly available scRNAseq data from mouse exocrine glands to identify their shared and unique characteristics. The aim of this review is to compare the role of MECs in maintaining healthy glandular function, their involvement in disease states, and their regenerative capacity, with a particular emphasis on the latest research findings in these areas.
Topics: Mice; Animals; Exocrine Glands; Epithelial Cells; Lacrimal Apparatus; Molecular Biology
PubMed: 38141817
DOI: 10.1016/j.jtos.2023.12.003 -
The American Journal of Dermatopathology Dec 2023Mixed tumor of the skin (MTS) is a tumor characterized by folliculosebaceous-apocrine differentiation. Because of the wide range of histological variations,...
Mixed tumor of the skin (MTS) is a tumor characterized by folliculosebaceous-apocrine differentiation. Because of the wide range of histological variations, understanding the unique features of MTS can help improve diagnosis. This study describes the histopathological characteristics of MTS, mainly apocrine-type MTS (AMT), using 166 cases of AMT. We found that nodular aggregates of myoepithelial cells, mucinous changes in the stroma, and follicular differentiation were standard characteristic features of MTS. Among the cases studied, 67% showed prominent follicular germinative cells and 40% showed prominent lipomatous metaplasia in the stroma. These cases often pose difficulties for the diagnosis of AMT because of insufficient evidence of sweat glands or myoepithelial cell differentiation. This is the first study to examine how the histological features of AMT change as the tumor extends deeper into the dermis. We found that the proportion of AMT with folliculosebaceous differentiation and large lumina increased as it got deeper into the dermis. Histopathological diagnosis of MTS is vital because the clinical symptoms lack specificity. This study enhances our understanding of the histopathological characteristics of MTS.
PubMed: 38133531
DOI: 10.1097/DAD.0000000000002600 -
Surgical Case Reports Dec 2023Adenomyoepithelioma (AME) of the breast is an uncommon tumor characterized by the proliferation of ductal epithelial and myoepithelial cells with the heterogeneity....
BACKGROUND
Adenomyoepithelioma (AME) of the breast is an uncommon tumor characterized by the proliferation of ductal epithelial and myoepithelial cells with the heterogeneity. Although benign AME is relatively easy to differentiate from breast cancer by core needle biopsy (CNB) alone, a definitive diagnosis is often difficult. The imaging findings of AME are also variable, and there are particularly few reports about radiological features, including contrast-enhanced magnetic resonance imaging (MRI) and apparent diffusion coefficient (ADC) values in AME.
CASE PRESENTATION
We present two cases of benign AME. Case 1 is a 30-year-old woman with a history of asthma. The cystic tumor shows smooth borders, and the intracystic solid component is irregular in shape and high vascularity. The pathological findings of the tumor were benign on CNB. The MRI scan showed a decreased ADC value. Case 2 is a 60-year-old woman with only a history of arrhythmia. The tumor shows a lobulated mass with cystic space and coarse calcifications. The pathological findings of the tumor were found to be benign by CNB. Dynamic MRI scan showed a fast washout pattern with a decreased ADC value. Both patients underwent excisional biopsy to confirm the diagnosis, and the pathological diagnosis was benign AME in both cases.
CONCLUSIONS
The AME of the breast has little specific imaging information, so it can be difficult to diagnose based on pathological findings of biopsy specimen. In our case, the ADC values were exceptionally low, contrary to previous reports. It is essential to carefully diagnose AME, considering the discrepancies in imaging findings observed in this case.
PubMed: 38123876
DOI: 10.1186/s40792-023-01793-7 -
Nature Communications Dec 2023Single-cell and spatial technologies that profile gene expression across a whole tissue are revolutionizing the resolution of molecular states in clinical samples....
Single-cell and spatial technologies that profile gene expression across a whole tissue are revolutionizing the resolution of molecular states in clinical samples. Current commercially available technologies provide whole transcriptome single-cell, whole transcriptome spatial, or targeted in situ gene expression analysis. Here, we combine these technologies to explore tissue heterogeneity in large, FFPE human breast cancer sections. This integrative approach allowed us to explore molecular differences that exist between distinct tumor regions and to identify biomarkers involved in the progression towards invasive carcinoma. Further, we study cell neighborhoods and identify rare boundary cells that sit at the critical myoepithelial border confining the spread of malignant cells. Here, we demonstrate that each technology alone provides information about molecular signatures relevant to understanding cancer heterogeneity; however, it is the integration of these technologies that leads to deeper insights, ushering in discoveries that will progress oncology research and the development of diagnostics and therapeutics.
Topics: Humans; Female; Tumor Microenvironment; Biomarkers, Tumor; Breast Neoplasms; Gene Expression Profiling; Transcriptome; Single-Cell Analysis
PubMed: 38114474
DOI: 10.1038/s41467-023-43458-x