When neglected for a long time, salivary gland pleomorphic adenoma (PA) can attain a considerable size, increasing the patient\'s morbidity along with the risk of malignant transformation. Very few case reports are available describing PA of the parotid glands presenting as a large cervicofacial mass. We report a case of epithelial myoepithelial carcinoma -a rare subtype of carcinoma ex-PA (Ca-Ex-PA) of non-luminal differentiation, that developed over a long period in a primary PA of the parotid gland and presented as a giant cervicofacial mass.

Background and Objectives: Mucin has been implicated via various mechanisms in the development and growth of tumour cells. However, mucin expression studies in salivary gland tumours are limited, especially with samples from minor salivary glands. This study aims to investigate and compare mucin expression in benign and malignant salivary gland tumours of minor and major salivary gland origins. Materials and Methods: Special stains were used to stain neutral mucin (Periodic acid Schiff), sialomucin (Alcian Blue) and sulfomucin (Aldehyde Fuschin) within tissues from six normal salivary glands and 73 salivary gland tumours including 31 pleomorphic adenomas, 27 mucoepidermoid carcinomas, and 15 adenoid cystic carcinomas. A semi-quantitative approach was used to evaluate mucin expression within ductal lumens. Sialomucin was the most expressed mucin in all salivary gland tumours, regardless of origin. Results: A significant difference was observed in the mucin expression between benign and malignant salivary gland tumours, as pleomorphic adenoma showed three times significantly higher expression of sialomucin compared to mucoepidermoid carcinoma and adenoid cystic carcinoma (p = 0.028). Pleomorphic adenomas of major glands showed 42 times significantly higher expression of sialomucin compared to those of minor glands (p = 0.000). Conclusions: Sialomucin content in pleomorphic adenomas of major glands was vastly increased compared to that in minor glands. Differential sialomucin expression in benign and malignant salivary gland tumours suggests a role in diagnosing of borderline salivary gland tumours.

OBJECTIVE: To investigate the added value of extracellular volume fraction (ECV) and arterial enhancement fraction (AEF) derived from enhanced CT to conventional image and clinical features for differentiating between pleomorphic adenoma (PA) and atypical parotid adenocarcinoma (PCA) pre-operation.
METHODS: From January 2010 to October 2023, a total of 187 cases of parotid tumors were recruited, and divided into training cohort (102 PAs and 51 PCAs) and testing cohort (24 PAs and 10 atypical PCAs). Clinical and CT image features of tumor were assessed. Both enhanced CT-derived ECV and AEF were calculated. Univariate analysis identified variables with statistically significant differences between the two subgroups in the training cohort. Multivariate logistic regression analysis with the forward variable selection method was used to build four models (clinical model, clinical model+ECV, clinical model+AEF, and combined model). Diagnostic performances were evaluated using receiver operating characteristic (ROC) curve analyses. Delong\'s test compared model differences, and calibration curve and decision curve analysis (DCA) assessed calibration and clinical application.
RESULTS: Age and boundary were chosen to build clinical model, and to construct its ROC curve. Amalgamating the clinical model, ECV, and AEF to establish a combined model demonstrated superior diagnostic effectiveness compared to the clinical model in both the training and test cohorts (AUC = 0.888, 0.867). There was a significant statistical difference between the combined model and the clinical model in the training cohort (p = 0.0145).
CONCLUSIONS: ECV and AEF are helpful in differentiating PA and atypical PCA, and integrating clinical and CT image features can further improve the diagnostic performance.

OBJECTIVE: To evaluate and compare the expression of E-cadherin, Snail1 and Twist1 in pleomorphic adenomas (PAs), adenoid cystic carcinomas (AdCCa) and carcinoma ex-pleomorphic adenomas (CaexPA) of salivary glands, as well as investigate possible associations with clinicopathological parameters.
METHODS: E-cadherin, Snail1 and Twist1 antibody immunostaining were analyzed semiquantitatively in 20 PAs, 20 AdCCas and 10 CaexPAs. Cases were classified as low and high expression for analysis of the association with clinicopathological parameters.
RESULTS: Compared to PAs, AdCCas and CaexPAs exhibited higher nuclear expression of Snail1 (p = 0.021 and p = 0.028, respectively) and Twist1 (p = 0.009 and p = 0.001). Membranous and cytoplasmic expression of E-cadherin were positively correlated in PAs, AdCCas and CaexPAs (r = 0.645, p = 0.002; r = 0.824, p < 0.001; r = 0.677, p = 0.031). In PAs, positive correlation was found between nuclear expression of Snail1 and membrane expression of E-cadherin (r = 0.634; p = 0.003), as well as between nuclear expression of Snail1 and Twist1 (r = 0.580; p = 0.007). Negative correlations were detected between membrane expression of E-cadherin and cytoplasmic expression of Snail1 in AdCCas (r = - 0.489; p = 0.029).
CONCLUSIONS: E-cadherin, Twist1, and Snail1 may participate in modulating events related to cell differentiation and adhesion in PAs and to biological behavior in AdCCas and CaexPAs, which indicates the involvement of EMT in these processes. Furthermore, the expression of these proteins in these carcinomas may reflect the plasticity feature of EMT.

Objective: To establish patient-derived organoid models of pleomorphic adenomas (PA) of the parotid gland and preliminarily characterize their histology, related biomarkers and functions. Methods: Fresh tumor tissue specimens were collected from surgical procedures of Oral and Maxillofacial Department. The harvested tissues were processed and cultured in a head and neck tumor organoid culture system to establish organoid models from parotid gland pleomorphic adenomas. The in vitro growth of PA organoids was recorded by light microscopy. The successfully established organoids were passaged and cryopreserved, and the cryopreserved PA organoids were revived and re-cultured to observe their viability and organoid regeneration ability. Histological characterization, as well as characterization and detection of related markers and functional proteins, were performed on the organoids, comparing them with the patient-derived tissues. Results: The constructed organoid model of pleomorphic adenoma exhibited a dense and compact three-dimensional spherical structure. Hematoxylin and eosin staining indicated morphological similarities between the organoid and its tissue of origin. Immunohistochemistry showed positive cytoplasmic staining for Calponin, cytokeratin 7, and epithelial membrane antigen in both the organoid and the source tumor tissue, suggesting consistent histopathological characteristics between the organoid and its tissue of origin. Periodic acid-Schiff staining of the organoid showed positive staining for glycogen, with positive staining located in the interior and periphery of the organoid, indicating that the organoid possessed secretory functions like the salivary gland. Conclusions: This study successfully constructed organoids of pleomorphic adenoma derived from patient samples. This model faithfully replicates the tissue morphology and biomarkers of the source tissue and exhibits biological functions associated with mucus secretion. It serves as a valuable in vitro model for studying the development and progression of salivary gland tumors.
目的： 构建患者来源腮腺多形性腺瘤（PA）类器官模型，并对其组织学、相关标志物和功能进行初步表征。 方法： 收集大连大学附属中山医院口腔颌面外科术中取材新鲜肿瘤组织标本，采用头颈部肿瘤类器官培养体系进行体外培养，构建腮腺PA类器官。观察PA类器官的体外生长情况并进行光镜拍摄。对培养成功的类器官进行传代和冻存，并对冻存的PA类器官进行复苏再培养，观测其活性和PA类器官再形成能力。对比患者来源组织，对PA类器官进行组织学表征，相关标志和功能蛋白进行表征与检测，评价PA类器官对来源组织的复现性。 结果： 构建的腮腺PA类器官形成紧实致密球状结构，HE染色提示类器官与其来源组织形态相似，免疫组化可见类器官及其来源肿瘤组织钙调蛋白、细胞角蛋白7、上皮膜抗原胞质阳性，提示类器官与其来源组织的病理学特征一致；PA类器官过碘酸希夫（PAS）染色及淀粉酶消化后PAS染色呈阳性，阳性着色位于类器官球体内部及外周，提示PA类器官具有类似于腮腺的分泌功能。 结论： 成功构建患者来源PA类器官，该模型在组织形态和标志物上可高度复现来源组织情况，并具有黏液分泌的生物学功能，是研究腮腺肿物发生发展的良好体外模型。.

Minor salivary glands are widely distributed in the mucosal surface of the lips, palate, nasal cavity, pharynx, and larynx, thus can arise from any of these primary sites. Intra-oral minor salivary gland tumors (IMSGTs), while considered rare in the general population are relatively more common when compared to all the other extra-oral sites. Pleomorphic adenoma, as seen in the index patient, is the most commonly diagnosed benign IMSGT. Intra-oral minor salivary gland tumors are not uncommon and depending on their size, nature, and location can be associated with severe limitation of the Patient\'s ability to breathe, speak clearly, and/or swallow and consequent severe morbidity and even mortality. In addition to these deleterious effects, they present a major surgical challenge to the surgeon, who has to determine the safest, most feasible access to ensure complete, or near-complete excision, as well as to the anesthetist, who needs to secure a definitive airway through the nose or mouth, both of which could be significantly restricted by the presence of the tumor. The aim is to present our successful management of one of the largest intra-oral minor salivary gland tumors documented in the literature, highlighting the specific measures we undertook to tackle the peculiar surgical and anesthetic challenges we faced. It had been two years since surgery and the patient is thriving with a markedly improved quality of life and no features of recurrence. The patient is a 50-year-old male with a slowly growing painless, left palatal mass in the roof of the mouth of 10 years duration with recurrent spontaneous bloody discharge effluent and snoring. There was an associated history of dysphagia to solid with associated choking spells, a left-sided facial asymmetry with no cheek swelling, odynophagia, sore throat, or difficulty with breathing. There was ipsilateral loss of upper incisors and dental anarchy about two years before presentation. No other nasal, otologic, or ophthalmic symptoms were present. No neck swelling, stiffness, cough, or chest symptoms. The oropharyngeal physical examination was highly restricted due to the intra-oral size of the mass. Figure 1. There was facial asymmetry with a bulge of the left maxilla, left-sided levels 1b and 2 non-tender lymph node enlargements, freely mobile, not adhered to the skin. A craniofacial CT scan revealed extensive isodense heterogeneously enhancing intra-oral soft tissue mass occupying the entire palate/oral cavity and encroaching laterally on the masticator and the parapharyngeal space with erosion of the left maxillary floor and hyoid bone Figure 2. The patient had an excision biopsy of the palatal mass with a free margin. No frozen section at the time of surgery. Histology revealed Pleomorphic adenoma and was followed up for 2 years with no evidence of recurrence. Prognosticators are delay in presentation leading to an increase in size of the mass and severe limitation of the patient\'s ability to breathe, speak clearly, and/or swallow and consequent severe morbidity and even mortality, the surgeon not being overwhelmed, the skillful Anaesthesist that could maneuver the nasal cavity without us doing tracheostomy and the successful outcome of the surgery.
Les glandes salivaires mineures sont largement réparties à la surface muqueuse des lèvres, du palais, de la cavité nasale, du pharynx et du larynx, et peuvent donc survenir à partir de l\'un de ces sites primaires. Les tumeurs des glandes salivaires mineures intra-orales (TGSMIO), bien que considérées comme rares dans la population générale, sont relativement plus courantes par rapport à tous les autres sites extra-oraux. L\'adénome pléomorphe, tel que celui observé chez le patient index, est la TGSMIO bénigne la plus fréquemment diagnostiquée. Les tumeurs des glandes salivaires mineures intra-orales ne sont pas rares et, en fonction de leur taille, de leur nature et de leur emplacement, peuvent être associées à une limitation sévère de la capacité du patient à respirer, à parler clairement et/ou à avaler, avec une morbidité sévère et même une mortalité. Outre ces effets délétères, elles présentent un défi chirurgical majeur pour le chirurgien, qui doit déterminer l\'accès le plus sûr et le plus faisable pour assurer une excision complète ou presque complète, ainsi que pour l\'anesthésiste, qui doit assurer une voie aérienne définitive par le nez ou la bouche, tous deux pouvant être significativement restreints par la présence de la tumeur. L\'objectif est de présenter notre prise en charge réussie de l\'une des plus grandes TGSMIO documentées dans la littérature, mettant en évidence les mesures spécifiques que nous avons prises pour relever les défis chirurgicaux et anesthésiques particuliers auxquels nous avons été confrontés. Deux ans après l\'intervention, le patient se porte bien avec une nette amélioration de sa qualité de vie et aucune manifestation de récurrence. Le patient est un homme de 50 ans présentant une masse palatine gauche en croissance lente et indolore dans le palais depuis 10 ans, avec des écoulements sanguins spontanés récurrents et des ronflements. Il y avait une histoire associée de dysphagie aux solides avec des épisodes d\'étouffement, une asymétrie faciale du côté gauche sans tuméfaction de la joue, une odynophagie, un mal de gorge ou des difficultés respiratoires. Il y avait une perte ipsilatérale des incisives supérieures et une anarchie entaire environ deux ans avant la présentation. Aucun autre symptôme nasal, otologique, ophtalmique n\'était présent. Aucun gonflement du cou, raideur, toux ou symptômes thoraciques. L\'examen physique de l\'oropharynx était fortement limité en raison de la taille intra-orale de la masse. Figure 1. Il y avait une asymétrie faciale avec une bosse du maxillaire gauche, des ganglions lymphatiques non douloureux des niveaux 1b et 2 du côté gauche, mobiles librement, non adhérents à la peau. La tomodensitométrie craniofaciale a révélé une masse tissulaire molle intraorale extensive, hétérogène, rehaussée de manière isodense occupant l\'ensemble du palais/cavité buccale et empiétant latéralement sur les muscles masticateurs et l\'espace parapharyngé, avec érosion du plancher du maxillaire gauche et de l\'os hyoïde. Figure 2. Le patient a subi une biopsie d\'excision de la masse palatine avec une marge libre. Aucune section congelée n\'a été réalisée lors de la chirurgie. L\'histologie a révélé un adénome pléomorphe et un suivi de 2 ans n\'a montré aucun signe de récurrence. Les facteurs pronostiques comprennent le retard de la présentation entraînant une augmentation de la taille de la masse et une limitation sévère de la capacité du patient à respirer, à parler clairement et/ou à avaler, avec une morbidité sévère voire une mortalité, le chirurgien ne se laissant pas dépasser, l\'anesthésiste compétent pouvant manœuvrer dans la cavité nasale sans avoir recours à une trachéotomie, et le succès de l\'intervention chirurgicale. MOTS-CLÉS: Intraoral; Glande salivaire mineure; Excision; Tumeur; Pronostiqueurs.

While acinic cell carcinoma (AciCC) can undergo high-grade transformation (HGT) to high-grade adenocarcinoma or poorly differentiated carcinoma, other morphologies such as spindle cell/sarcomatoid carcinoma are rare and not well-characterized. We herein report a novel case of AciCC with squamoglandular and chondrosarcomatous HGT mimicking a so-called \'carcinosarcoma ex-pleomorphic adenoma\'. The patient is an 81-year-old male with a two-month history of neck swelling and referred otalgia who presented with a left parapharyngeal space mass extending into retropharyngeal space and pterygoid muscles. On resection, the tumor showed considerable morphologic diversity with high-grade serous and mucous acinar components as well as cribriform to solid apocrine-like components with comedonecrosis and squamous differentiation, all of which were embedded in a chondromyxoid background ranging from paucicellular and bland to a high-grade chondrosarcoma/pleomorphic sarcoma-like appearance. Only a minor conventional AciCC component was noted. Immunostains were negative for AR and only focally positive for GCDFP-15 arguing against a true apocrine phenotype, while PLAG1 and HMGA2 were negative arguing against an antecedent pleomorphic adenoma. On the other hand, SOX-10, DOG-1 and PAS after diastase highlighted serous acinar differentiation, and mucicarmine, and NKX3.1 highlighted mucous acinar differentiation. NR4A3 immunohistochemical staining and NR4A3 fluorescence in situ hybridization were positive in the carcinomatous and sarcomatoid components while sequencing analysis of both components revealed identical alterations involving TP53, PIK3CB, ARID1A, and STK11. This unique case warrants caution in designating all salivary sarcomatoid carcinomas with heterologous elements as part of the \'carcinoma ex-pleomorphic adenoma\' family.

Salivary gland neoplasms account for 3% of all head and neck tumours. Pleomorphic adenoma (PA) is the most common salivary gland tumour that mainly occurs in the parotid gland, followed by minor salivary glands of the oral cavity, however, the occurrence of PA inside the jaw bones is exceedingly rare and very few cases have been reported in the literature. Inside jaw bones these lesions tend to imitate large osteolytic lesions encompass a diagnostic challenge. An exhaustive review of the literature revealed only 10 cases of central pleomorphic adenoma. We present a rare case of primary PA that occurred inside the mandible and was provisionally diagnosed as ameloblastoma.

Calcification within pleomorphic adenomas of the lacrimal gland is well recognized but uncommon, being seen more readily in lacrimal gland carcinomas. Bony formation, ossification, in pleomorphic adenomas of the lacrimal glands is even rarer. Together with extensive sclerosis, or \"coagulative necrosis,\" ossification and necrosis should alert the clinician to the risk of malignant transformation. However, both can mimic carcinomatous change, leading to misinterpretation of malignancy in an otherwise benign lacrimal gland neoplasm. We present 2 case reports of patients with clinically presumed pleomorphic adenomas of the lacrimal gland whose histopathology demonstrated lacrimal gland ossification and necrosis without features of malignancy or invasive disease.

Parotid lumps are a heterogeneous group of mainly benign but also malignant tumors. Preoperative imaging does not allow a differentiation between tumor types. Multispectral optoacoustic tomography (MSOT) may improve the preoperative diagnostics. In this first prospective pilot trial the ability of MSOT to discriminate between the two most frequent benign parotid tumors, pleomorphic adenoma (PA) and Warthin tumor (WT) as well as to normal parotid tissue was explored. Six wavelengths (700, 730, 760, 800, 850, 900 nm) and the parameters deoxygenated (HbR), oxygenated (HbO2), total hemoglobin (HbT), and saturation of hemoglobin (sO2) were analyzed. Ten patients with PA and fourteen with WT were included (12/12 female/male; median age: 51 years). For PA, the mean values for all measured wave lengths as well as for the hemoglobin parameters were different for the tumors compared to the healthy parotid (all p < 0.05). The mean MSOT parameters were all significantly higher (all p < 0.05) in the WT compared to healthy parotid gland except for HbT and sO2. Comparing both tumors directly, the mean values of MSOT parameters were not different between PA and WT (all p > 0.05). Differences were seen for the maximal MSOT parameters. The maximal tumor values for 900 nm, HbR, HbT, and sO2 were lower in PA than in WT (all p < 0.05). This preliminary MSOT parotid tumor imaging study showed clear differences for PA or WT compared to healthy parotid tissue. Some MSOT characteristics of PA and WT were different but needed to be explored in larger studies.