The objective of this study is to provide a comprehensive classification system for parotidectomy operations. Data sources include Medline publications, author’s experience, and consensus round table ...at the Third European Salivary Gland Society (ESGS) Meeting. The Medline database was searched with the term “parotidectomy” and “definition”. The various definitions of parotidectomy procedures and parotid gland subdivisions extracted. Previous classification systems re-examined and a new classification proposed by a consensus. The ESGS proposes to subdivide the parotid parenchyma in five levels: I (lateral superior), II (lateral inferior), III (deep inferior), IV (deep superior), V (accessory). A new classification is proposed where the type of resection is divided into formal parotidectomy with facial nerve dissection and extracapsular dissection. Parotidectomies are further classified according to the levels removed, as well as the extra-parotid structures ablated. A new classification of parotidectomy procedures is proposed.
Objective
A major characteristic of the autoimmune disease primary Sjögren's syndrome (SS) is salivary gland (SG) hypofunction. The inability of resident SG stem cells (SGSCs) to maintain homeostasis ...and saliva production has never been explained and limits our comprehension of mechanisms underlying primary SS. The present study was undertaken to investigate the role of salivary gland stem cells in hyposalivation in primary SS.
Methods
SGSCs were isolated from parotid biopsy samples from controls and patients classified as having primary SS or incomplete primary SS, according to the American College of Rheumatology/European League Against Rheumatism criteria. Self‐renewal and differentiation assays were used to determine SGSC regenerative potential, RNA was extracted for sequencing analysis, single telomere length analysis was conducted to determine telomere length, and frozen tissue samples were used for immunohistochemical analysis.
Results
SGSCs isolated from primary SS parotid gland biopsy samples were regeneratively inferior to healthy control specimens. We demonstrated that SGSCs from samples from patients with primary SS are not only lower in number and less able to differentiate, but are likely to be senescent, as revealed by telomere length analysis, RNA sequencing, and immunostaining. We further found that SGSCs exposed to primary SS–associated proinflammatory cytokines we induced to proliferate, express senescence‐associated genes, and subsequently differentiate into intercalated duct cells. We also localized p16+ senescent cells to the intercalated ducts in primary SS SG tissue, suggesting a block in SGSC differentiation into acinar cells.
Conclusion
This study represents the first characterization of SGSCs in primary SS, and also the first demonstration of a linkage between an autoimmune disease and a parenchymal premature‐aging phenotype. The knowledge garnered in this study indicates that disease‐modifying antirheumatic drugs used to treat primary SS are not likely to restore saliva production, and should be supplemented with fresh SGSCs to recover saliva production.
Abstract
Objective
Salivary gland (SG) progenitor cells (SGPCs) maintain SG homeostasis. We have previously shown that in primary Sjögren’s syndrome (pSS), SGPCs are likely to be senescent, and may ...underpin SG dysfunction. This study assessed the extent of senescence of cells in a SGPC niche in pSS patients’ SGs, and its correlation with functional and clinical parameters.
Methods
The expression of p16 and p21 as markers of senescence in both total SG epithelium and a SGPC niche (basal striated duct cells, BSD) was examined in SGs of pSS (n = 35), incomplete pSS (n = 13) (patients with some signs of pSS, but not fulfilling all classification criteria) and non-SS sicca control (n = 21) patients. This was correlated with functional and clinical parameters.
Results
pSS patient SGs contained significantly more p16+ cells both in the epithelium in general (P <0.01) and in the BSD layer (P <0.001), than non-SS SGs. Significant correlations were found in pSS patients between p16+ BSD cells and secretion of unstimulated whole saliva, stimulated whole saliva, stimulated parotid saliva, CD45+ infiltrate, ultrasound total score and ACR-EULAR classification score, but not with EULAR Sjögren’s syndrome disease activity index (ESSDAI) and EULAR Sjögren’s Syndrome Patient Reported Index (ESSPRI) scores. Correlations with total epithelium p16+ cells were weaker. Incomplete pSS patients also had increased numbers of p16+ epithelial and BSD cells. Based on protein and mRNA expression, p21+ appears not to play a significant role in the SG in pSS.
Conclusion
These findings suggest SGPC senescence may be an early feature of primary Sjögren’s syndrome and may contribute to defective SG function in pSS but not to systemic disease activity.
Background
Enucleation has been reported as a minimally invasive surgery for Warthin's tumor (WT). However, the definite indications for enucleation have not been clarified.
Methods
Enucleation was ...indicated by the following findings: findings of WT, cystic fluid, or benign leukocytes by fine‐needle aspiration cytology; a well‐margined and homogeneous pattern on imaging; and a tumor location in the tail or preauricular area of the parotid gland. We reviewed 552 cases treated with parotid gland surgery in our hospital.
Results
A total of 108 tumors were treated with enucleation and included no malignant solid tumors or pleomorphic adenoma. Enucleation demonstrated low invasiveness and complication rates. Revision surgery for WT reappearance after enucleation was rare and showed minimal scarring, with a lower risk of facial weakness.
Conclusions
The indication criteria for enucleation were validated. Such enucleation is useful, as it is associated with minimal invasiveness, low complication rates, and safety in revision surgery.
Salivary gland tumors constitute 2%-6% of all head and neck tumors and are most common in the parotid gland. Magnetic resonance (MR) imaging is the most sensitive imaging modality for diagnosis. ...Tumor type, localization, and relationship with surrounding structures are important factors for treatment. Therefore, parotid gland tumor segmentation is important. Specialists widely use manual segmentation in diagnosis and treatment. However, considering the development of artificial intelligence-based models today, it is seen that artificial intelligence-based automatic segmentation models can be used instead of manual segmentation, which is a time-consuming technique. Therefore, we segmented parotid gland tumor (PGT) using deep learning-based architectures in the paper.
The dataset used in the study includes 102 T1-w, 102 contrast-enhanced T1-w (T1C-w), and 102 T2-w MR images. After cropping the raw and manually segmented images by experts, we obtained the masks of these images. After standardizing the image sizes, we split these images into approximately 80% training set and 20% test set. Hereabouts, we trained six models for these images using ResNet18 and Xception-based DeepLab v3+. We prepared a user-friendly Graphical User Interface application that includes each of these models.
From the results, the accuracy and weighted Intersection over Union values of the ResNet18-based DeepLab v3+ architecture trained for T1C-w, which is the most successful model in the study, are equal to 0.96153 and 0.92601, respectively. Regarding the results and the literature, it can be seen that the proposed system is competitive in terms of both using MR images and training the models independently for T1-w, T1C-w, and T2-w. Expressing that PGT is usually segmented manually in the literature, we predict that our study can contribute significantly to the literature.
In this study, we prepared and presented a software application that can be easily used by users for automatic PGT segmentation. In addition to predicting the reduction of costs and workload through the study, we developed models with meaningful performance metrics according to the literature.
Solitary plasmacytoma is a rare neoplasm of monoclonal plasma cells that falls along the spectrum of plasma cells dyscrasias. Unlike bone plasmacytomas, extramedullary plasmacytomas occur outside the ...bone marrow in any soft tissue. The aerodigestive tract is the most common site, but any organ, including the parotid gland, may be rarely involved. Extramedullary plasmacytoma lacks the defining features of multiple myeloma or medullary plasmacytoma. Here, we report a case of a 60-year-old man who presented with a mass in the retro-auricular area of 2 months’ duration. On physical examination, a 2-cm mass was palpated in the right parotid area with no palpable cervical lymph nodes. Fine-needle aspiration cytology showed atypical cells. MRI of the head and neck showed a 2x2-cm mass in the parotid tail with features suggestive of muco-epidermoid carcinoma and absence of lymphadenopathies. Total parotidectomy was performed. Histopathological evaluation revealed monoclonal plasma cells expressing kappa immunoglobulin light chains. To complete the workup, serum protein electrophoresis, immunofixation, quantitation of immunoglobulins and urine protein electrophoresis, and Bence-Jones were normal. A whole-body 18F-FDG PET/CT scan did not reveal any other lesions. Bone marrow aspirate and biopsy demonstrated less than 3% clonal plasma cells. A complete blood count showed a normal hemoglobin level. Chemistry screen revealed normal calcium and creatinine levels. A diagnosis of solitary plasmacytoma of the parotid gland was made, and the patient received post-operation radiation therapy to the right parotid area. Because less than 7% of patients with solitary medullary plasmacytoma will develop local recurrence and approximately 10–15% of patients will ultimately develop multiple myeloma, the patient was followed up by laboratory tests and imaging at periodic intervals; he is still in complete remission. Although patients with parotid masses are commonly observed in our practice, parotid plasmacytoma is rare. Despite its rarity, it should be considered in the differential diagnosis of parotid gland tumors. Biopsy, blood tests, and imaging are important in the accurate diagnosis and management of this neoplasm.
Background
The aim of the present study was to establish a competing risk nomogram to predict parotid gland cancer‐specific mortality (PGC‐SM).
Methods
Seven thousand nine hundred and sixty‐two ...patients extracted from SEER database were randomly categorized into training and validation sets. The competing risk model was used to identify factors associated with PGC‐SM. The nomogram was evaluated via concordance indexes (C‐indexes), calibration plots, and decision curve analysis (DCA).
Results
Male, elderly, white, widowed, larger tumor, no surgery, advanced tumor grade, lymph node (LN) metastasis, adenocarcinoma (ADC), and higher TNM stage were associated with higher incidence of PGC‐SM. Calibration plots showed that the nomogram was well calibrated. C‐indexes for nomogram were 0.84 (95% CI: 0.81–0.86) and 0.84 (95% CI: 0.82–0.86) in training and validation sets, respectively. DCA demonstrated the clinical usefulness of nomogram.
Conclusions
The competing risk nomogram shows high performance in predicting PGC‐SM, which might enable clinicians formulate suitable treatment protocols for patients with parotid gland carcinoma (PGC).
Surgeons used to be unaware of the facial nerve's position during parotid surgery. Now, with special magnetic resonance imaging (MRI) sequences, it can be located and converted into a 3D model ...displayed on an augmented reality (AR) device for surgeons to study and manipulate. This study explores the accuracy and usefulness of the technique for the treatment of benign and malignant parotid tumours. A total of 20 patients with parotid tumours had 3-Tesla MRI scans, and their anatomical structures were segmented using Slicer software. The structures were imported into a Microsoft HoloLens 2® device, displayed in 3D, and shown to the patient for consent. Intraoperative video recording was used to record the position of the facial nerve in relation to the tumour. The predicted path of the nerve taken from the 3D model was combined with surgical observation and video recording in all cases. The imaging proved to have application in both benign and malignant disease. It also improved the process of informed patient consent. Three-dimensional MRI imaging of the facial nerve within the parotid gland and its display in a 3D model is an innovative technique for parotid surgery. Surgeons can now see the nerve's position and tailor their approach to each patient's tumour, providing personalised care. The technique eliminates the surgeon's blind spot and is a significant advantage in parotid surgery.
Publications relating parotid dose-volume characteristics to radiotherapy-induced salivary toxicity were reviewed. Late salivary dysfunction has been correlated to the mean parotid gland dose, with ...recovery occurring with time. Severe xerostomia (defined as long-term salivary function of <25% of baseline) is usually avoided if at least one parotid gland is spared to a mean dose of less than approximately 20 Gy or if both glands are spared to less than approximately 25 Gy (mean dose). For complex, partial-volume RT patterns (e.g., intensity-modulated radiotherapy), each parotid mean dose should be kept as low as possible, consistent with the desired clinical target volume coverage. A lower parotid mean dose usually results in better function. Submandibular gland sparing also significantly decreases the risk of xerostomia. The currently available predictive models are imprecise, and additional study is required to identify more accurate models of xerostomia risk.
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