Unicentric Castleman's disease in the parotid gland associated with psoriasis: a case report.

BACKGROUND: Castleman's disease is a rare lymphoproliferative disorder that is often misdiagnosed because of its untypical clinical or imaging features except for a painless mass. Besides, it is also difficult to cure Castleman's disease due to its unclear pathogenesis. CASE PRESENTATION: We present a Castleman's disease case with diagnostic significance regarding a 54-year-old Chinese male who has a painless mass in his left parotid gland for 18 months with a 30-years history of autoimmune disease psoriasis. Computed tomography scan showed a high-density nodule with clear boundaries in the left parotid and multiple enlarged lymph nodes in the left submandibular and neck region. General checkup, the extremely elevated serum interleukin-6 and lymph node biopsy in the left submandibular region gave us an initial suspicion of Castleman's disease. Then the patient underwent a left superficial parotidectomy. Based on histopathologic analysis, we made a certain diagnosis of Castleman's disease and gave corresponding treatments. In 18 months of follow-up, the patient showed no evidence of recurrence, with the level of serum interleukin-6 decreased. CONCLUSIONS: Clinicians should be aware of the possibility of Castleman's disease when faced with masses or enlarged lymph nodes in the parotid gland to avoid misdiagnosis, especially in patients with autoimmune diseases and elevated serum interleukin-6.

Persistent bleeding following biopsy of an epidermoid cyst within the parotid gland.

Epidermoid cysts are benign lesions most commonly found in the skin but which can arise in many other locations including, very rarely the salivary glands. This rarity often leaves them off standard differential lists and can create a diagnostic dilemma. A patient with an incidentally detected parotid mass on MRI underwent core biopsy, which was unfortunately complicated by formation of a pseudoaneurysm and persistent arterial bleeding requiring coil embolisation. The histology showed only keratinous material and, in retrospect, the signal characteristics of the mass were entirely typical of an epidermoid cyst. Recognition of this common, benign entity in a very rare location can obviate the need for invasive tests and potential complications and direct management to more appropriate imaging follow-up.

The value of MRI-based radiomics for evaluating early parotid gland injury in primary Sjögren's syndrome.

OBJECTIVE: This study aimed to evaluate the value of machine learning models (ML) based on MRI radiomics in diagnosing early parotid gland injury in primary Sjögren's syndrome (pSS). METHODS: A total of 164 patients (114 in the training cohort and 50 in the testing cohort) with pSS (n=82) or healthy controls (HC) (n=82) were enrolled. Itksnap software was used to perform two-dimensional segmentation of the bilateral parotid glands on T1-weighted (T1WI) and fat-suppressed T2-weighted imaging (fs-T2WI) images. A total of 1548 texture features of the parotid glands were extracted using radiomics software. A radiomics score (Radscore) was constructed and calculated. A t-test was used to compare the Radscore between the two groups. Finally, five machine learning models were trained and tested to identify early pSS parotid injury, and the performance of the machine learning models was evaluated by calculating the acceptance operating curve (ROC) and other parameters. RESULTS: The Radscores between the pSS and HC groups showed significant statistical differences (p<0.001). Among the five machine learning models, the Extra Trees Classifier (ETC) model performed high predictive efficacy in identifying early pSS parotid injury, with an AUC of 0.87 in the testing set. CONCLUSION: MRI radiomics-based machine learning models can effectively diagnose early parotid gland injury in primary Sjögren's syndrome.

Partial facial paralysis induced by sialolithiasis of the parotid gland: a case report.

BACKGROUND: Facial paralysis due to parotid sialolithiasis-induced parotitis is a unusual clinical phenomenon that has not been reported in prior literature. This scenario can present a diagnostic challenge due to its rarity and complex symptomatology, particularly if a patient has other potential contributing factors such as facial trauma or bilateral forehead botox injections as in this patient. This case report elucidates such a complex presentation, aiming to increase awareness and promote timely recognition among clinicians. CASE PRESENTATION: A 56-year-old male, with a medical history significant for hyperlipidemia, recurrent parotitis secondary to parotid sialolithiasis, and recent bilateral forehead cosmetic Botox injections presented to the emergency department with right lower facial drooping. This onset was about an hour after waking up and was of 4 h duration. The patient also had a history of a recent ground level fall four days prior that resulted in facial trauma to his right eyebrow without any evident neurological deficits in the region of the injury. A thorough neurological exam revealed sensory and motor deficits across the entirety of the right face, indicating a potential lesion affecting the buccal and marginal mandibular branches of the facial nerve (CN VII). Several differential diagnoses were considered for the lower motor neuron lesion, including soft tissue trauma or swelling from the recent fall, compression due to the known parotid stone, stroke, and complex migraines. An MRI of the brain was conducted to rule out a stroke, with no significant findings. A subsequent CT scan of the neck revealed an obstructed and dilated right Stensen's duct with a noticeably larger and anteriorly displaced sialolith and evidence of parotid gland inflammation. A final diagnosis of facial palsy due to parotitis secondary to sialolithiasis was made. The patient was discharged and later scheduled for a procedure to remove the sialolith which resolved his facial paralysis. CONCLUSIONS: This case emphasizes the need for a comprehensive approach to the differential diagnosis in presentations of facial palsy. It underscores the potential involvement of parotid sialolithiasis, particularly in patients with a history of recurrent parotitis or facial trauma. Prompt recognition of such uncommon presentations can prevent undue interventions, aid in timely appropriate management, and significantly contribute to the patient's recovery and prevention of long-term complications.

Diagnostic Challenges and Imaging Considerations for Intraparotid Facial Nerve Schwannoma: A Case Report and Literature Review.

BACKGROUND A mass in the parotid gland usually indicates parotid gland neoplasia. Warthin tumors or pleomorphic adenomas are common differential diagnoses. Less frequently, other differential diagnoses and sites of origin are considered. Schwannomas are rare, benign tumors in the head and neck region. Even more rarely, these tumors occur in the intraparotid course of the facial nerve. In the following, we report about 2 patients in whom a mass in the right parotid gland was found incidentally during magnetic resonance imaging (MRI). CASE REPORT We reviewed data from the literature on intraparotid facial nerve schwannomas (IPFNS) and compared them with those from our cases. The focus was on data such as clinical history, clinical symptoms, electroneurography, and various imaging modalities, such as ultrasonography and MRI combined with diffusion-weighted imaging. CONCLUSIONS It is challenging to distinguish facial nerve schwannomas from other neoplasms. Patient's history, clinical symptoms, MRI examination with diffusion-weighted imaging, and high-resolution ultrasound imaging are decisive factors for diagnosis and should be performed when IPFNS is suspected. Diagnosis and therapy for IPFNS remain challenging. A wait-and-scan approach could be an option for patients with small tumors and good facial nerve function. On the other hand, patients with advanced tumors associated with limited facial nerve function can benefit from surgical approaches or stereotactic radiosurgery.

Correlation between MRI (DWI and DCE) and cellularity of parotid gland pleomorphic adenomas.

PURPOSE: Parotid pleomorphic adenomas present a risk of recurrence, higher when the tumour is a hypocellular subtype. The aim of the study was to determine whether it is possible to characterize this histological subtype with diffusion and perfusion sequences of the preoperative MRI. METHODS: This retrospective study included 97 patients operated between 2010 and 2020. Histologic slides review was performed to classify tumours into three histologic subtypes: hypocellular, classical and hypercellular. Univariate and multivariate analyses studied the correlation between histology and diffusion and perfusion MRI parameters obtained with OleaSphere® software. RESULTS: The hypocellular subtype had higher apparent diffusion coefficient values than the other two subtypes: 2.13 ± 0.23, 1.83 ± 0.42, and 1.61 ± 0.4 × 10-3 mm2/s for hypocellular, classical and hypercellular subtype respectively (p < 0.0001). Multivariate analysis showed that an ADCmean > 1.88 × 10-3 mm2/s was suggestive of a hypocellular pleomorphic adenoma in 79% of the cases, with a specificity and PPV of 94 and 96% (p < 0.001), respectively. CONCLUSION: The histological subtype of a pleomorphic adenoma can be predicted preoperatively with ADC values. A prospective and multicentric study on a larger cohort is needed to confirm our results.

Anti-centromere antibody positivity is an independent variable associated with salivary gland ultrasonography score in Sjögren's syndrome.

Sjögren's syndrome (SS) is an autoimmune disease characterized by periductal lymphocytic infiltration of the salivary and lacrimal glands. SS also exhibits extra-glandular manifestations and specific autoantibodies. Salivary gland ultrasonography (SGUS) is a common procedure used to assess the severity of glandular involvement. However, the association between SGUS and extra-glandular lesions remains poorly understood. This study aimed to identify clinical indices, including disease activity, associated with glandular involvement using SGUS in patients with SS. We included 115 patients with SS and 90 without SS. Patients with SS had significantly higher ultrasonography (US) score than patients without SS. Multivariate analysis revealed focus score, Saxon test positivity, and anti-centromere antibody (ACA) positivity as independent variables associated with the US score in patients with SS. In addition, these results were similar to those obtained in patients with primary SS. Patients with SS and ACA positivity had higher US score and an increased prevalence of hyperechoic bands in the parotid glands and submandibular glands. In conclusion, this study indicated that ACA positivity is associated with the US score in patients with SS. These results suggest that US findings in patients with ACA positivity might show specific changes in the salivary glands, especially fibrosis.

Evaluation of major salivary glands with ultrasonography in multiple sclerosis patients.

BACKGROUND: This study aimed to investigate the homogeneity of the major salivary glands in multiple sclerosis (MS) patients using ultrasonography (USG), assess DMFT indices, measure resting salivary flow rates, and compare these values with healthy individuals. METHODS: In this study, 20 individuals diagnosed with Relapsing-Remitting Multiple Sclerosis (RRMS) (mean age 36.15 ± 8.51) and 20 systemically healthy individuals (mean age 35.7 ± 9.22) were included. Oral and radiologic examinations were performed in all individuals. The parotid and submandibular salivary glands were examined using USG, and their homogeneity was assessed based on the scoring system recommended by the Outcome Measures in Rheumatology Clinical Trials (OMERACT) study group. Resting salivary flow rates and DMFT indices were measured, and the obtained data were subjected to statistical analysis. RESULTS: The parotid glands exhibited more heterogeneity on USG within the MS patient group than the control group, with a statistically significant difference between the two groups (p = 0.015). A statistically significant correlation was observed in total homogeneity values between the patient and control groups (p = 0.021). Furthermore, the MS patient group exhibited higher DMFT indices and lower salivary flow rates than the control group. The difference between the DMFT indices and salivary flow rate between the patient groups was statistically significant (p = 0.004 and p = 0.002 respectively). CONCLUSIONS: The parenchyma of the major salivary glands in MS patients exhibited decreased homogeneity than the healthy controls. Additionally, the MS group showed a decrease in salivary flow rate and an increase in the DMFT index. Autonomic dysfunction and medications used for MS are thought to cause salivary gland hypofunction and dry mouth. It can be interpreted that hyposalivation and motor skill losses in MS patients lead to an increase in DMFT index.

Multiple metastasis of malignant melanoma. The diagnostic role of ultrasonography starting from a parotid tumor.

We presented the case of a patient with a slowly developing right parotid tumor over the course of several years. Multimodal ultrasonography proved relevant for malignancy. Subsequent imaging identified tumors in numerous organs, considered metastases. Ultrasonography consolidated all identified aspects. Biopsy from an adrenal mass and histological examination evidenced the presence of a malignant, metastatic melanoma with cutaneous origin. Considerations are made regarding the role of ultrasonography in such cases.

PSMA PET/CT as a predictive tool for subregional importance estimates in the parotid gland.

Objective. Xerostomia and radiation-induced salivary gland dysfunction remain a common side effect for head-and-neck radiotherapy patients, and attempts have been made to quantify the heterogeneity of the dose response within parotid glands. Prostate Specific Membrane Antigen (PSMA) ligands have demonstrated high uptake in salivary glands, which has been shown to correlate with gland functionality. Here we compare several models of parotid gland subregional relative importance with PSMA positron emission tomography (PET) uptake. We then develop a predictive model for Clarket al's relative importance estimates using PSMA PET and CT radiomic features, and demonstrate a methodology for predicting patient-specific importance deviations from the population.Approach. Intra-parotid gland uptake was compared with four regional importance models using 30 [18F]DCFPyL PSMA PET images. The correlation of uptake and importance was ascertained when numerous non-overlapping subregions were defined, while a paired t-test was used to compare binary region pairs. A radiomics-based predictive model of population importance was developed using a double cross-validation methodology. A model was then devised for supplementing population-level subregional importance estimates for each patient using patient-specific radiomic features.Main Results. Anticorrelative relationships were found to exist between PSMA PET uptake and four independent models of subregional parotid gland importance from the literature. Kernel Ridge Regression with principal component analysis feature selection performed best over test sets (Mean Absolute Error = 0.08), with gray level co-occurrence matrix (GLCM) features being particularly important. Deblurring PSMA PET images with neural blind deconvolution strengthened correlations and improved model performance.Significance. This study suggests that regions of relatively low PSMA PET uptake in parotid glands may exhibit relatively high dose-sensitivity. We've demonstrated the utility of PSMA PET radiomic features for predicting relative importance within subregions of parotid glands. PSMA PET appears to be a promising quantitative imaging modality for analyzing salivary gland functionality.

Intra-parotid facial nerve path by MRI tractography: radio-clinical comparison in parotid tumors.

PURPOSE: The objective of our study was to evaluate the ability of preoperative MRI tractography to visualize and predict the path of the facial nerve with respect to an intra-parotid mass. METHODS: We performed an observational bicentric study from June 2019 to August 2020. All patients older than 18 years old, treated for a parotid mass with surgical indication, without MRI contraindication and who agreed to participate in the study were enrolled prospectively. All patients underwent a cervico-facial MRI with tractographic analysis. Postprocessed tractography images of the intra-parotid facial nerve were analyzed by two expert radiologists in head and neck imaging. The intraoperative anatomical description of the facial nerve path and its relationship to the mass was performed by the surgeon during the operation, with no visibility on MRI examination results. A statistical study allowed for the description of the data collected as well as the measurement of inter-observer agreement and agreement between tractography and surgery using kappa coefficients. RESULTS: Fifty-two patients were included. The facial nerve trunk and its first two divisional branches were visualized via tractography in 93.5% of cases (n = 43). The upper distal branches were visualized in 51.1% of cases (n = 23), and the lower branches were visualized in 73.3% of cases (n = 33). Agreement with the location described per-operatively was on average 82.9% for the trunk, 74.15% for the temporal branch, and 75.21% for the cervico-facial branch. CONCLUSION: Fiber tractography analysis by MRI of the intra-parotid facial nerve appears to be a good test for predicting the path of the nerve over the parotid mass and could be an additional tool to guide the surgeon in the operative procedure.

Deep Network-Based Comprehensive Parotid Gland Tumor Detection.

RATIONALE AND OBJECTIVES: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Construction and Application of a Nomogram for Predicting Benign and Malignant Parotid Tumors.

OBJECTIVE: A prediction model of benign and malignant differentiation was established by magnetic resonance signs of parotid gland tumors to provide an important basis for the preoperative diagnosis and treatment of parotid gland tumor patients. METHODS: The data from 138 patients (modeling group) who were diagnosed based on a pathologic evaluation in the Department of Stomatology of Jilin University from June 2019 to August 2021 were retrospectively analyzed. The independent factors influencing benign and malignant differentiation of parotid tumors were selected by logistic regression analysis, and a mathematical prediction model for benign and malignant tumors was established. The data from 35 patients (validation group) who were diagnosed based on pathologic evaluation from September 2021 to February 2022 were collected for verification. RESULTS: Univariate and multivariate logistic regression analysis showed that tumor morphology, tumor boundary, tumor signal, and tumor apparent diffusion coefficient (ADC) were independent risk factors for predicting benign and malignant parotid gland tumors ( P < 0.05). Based on multivariate logistic regression analysis of the modeling group, a mathematical prediction model was established as follows: Y = the ex/(1 + ex) and X = 0.385 + (1.416 × tumor morphology) + (1.473 × tumor border) + (1.306 × tumor signal) + (2.312 × tumor ADC value). The results showed that the area under the receiver operating characteristic curve of the model was 0.832 (95% confidence interval, 0.75-0.91), the sensitivity was 82.6%, and the specificity was 70.65%. The validity of the model was verified using validation group data, for which the sensitivity was 85.71%, the specificity was 96.4%, and the correct rate was 94.3%. The results showed that the area under receiver operating characteristic curve was 0.936 (95% confidence interval, 0.83-0.98). CONCLUSIONS: Combined with tumor morphology, tumor ADC, tumor boundary, and tumor signal, the established prediction model provides an important reference for preoperative diagnosis of benign and malignant parotid gland tumors.

Characterization of parotid gland tumors: Whole-tumor histogram analysis of diffusion weighted imaging, diffusion kurtosis imaging, and intravoxel incoherent motion - A pilot study.

PURPOSE: To investigate the diagnostic performance of histogram features of diffusion parameters in characterizating parotid gland tumors. METHOD: From December 2018 to January 2023, patients who underwent diffusion weighted imaging (DWI), diffusion kurtosis imaging (DKI), and intravoxel incoherent motion (IVIM) were consecutively enrolled in this retrospective study. The histogram features of diffusion parameters, including apparent diffusion coefficient (ADC), diffusion coefficient (Dk), diffusion kurtosis (K), pure diffusion coefficient (D), pseudo-diffusion coefficient (DP), and perfusion fraction (FP) were analyzed. The Mann-Whitney U test was used for comparison between benign parotid gland tumors (BPGTs) and malignant parotid gland tumors (MPGTs). Receiver operating characteristic curve and logistic regression analysis were used to identify the differential diagnostic performance. The Spearman's correlation coefficient was used to analyze the correlation between diffusion parameters and Ki-67 labeling index. RESULTS: For diffusion MRI, twenty-three histogram features of diffusion parameters showed significant differences between BPGTs and MPGTs (all P < 0.05). Compared with the DWI model, the IVIM model and combined model had better diagnostic specificity (58 %, 94 %, and 88 %, respectively; both corrected P < 0.001) and accuracy (64 %, 89 %, and 86 %, respectively; both corrected P = 0.006). The combined model was superior to the single DWI model with improved IDI (IDI improvement 0.25). Significant correlations were found between Ki-67 and ADCmean, Dkmean, Kmean, and Dmean (r = -0.57 to 0.53; all P < 0.05). CONCLUSIONS: Whole-tumor histogram analysis of IVIM and combined diffusion model could further improve the diagnostic performance for differentiating BPGTs from MPGTs.

Ultrasound-guided thread lifting for the prevention of parotid gland and diagnosing parotid duct complications.

BACKGROUND: Thread lifting is a common minimally invasive plastic surgery procedure. Parotid gland injury caused by thread lifting is a known complication; however, visual evidence of this complication is lacking. OBJECTIVES: This study aimed to present cases of parotid gland injury by thread lifting shown using ultrasound and to discuss the importance of ultrasound detection of the location of the parotid gland before thread insertion. METHODS: This study included eight patients diagnosed with parotid gland perforation and one with parotid duct injury due to threads from November 2020 to October 2022. RESULTS: Six patients showed tenderness and swelling, three were asymptomatic, and one with duct injury showed severe swelling and pain. Although the severity and duration of symptoms have differed, we confirmed the progress of improvement with conservative treatment and confirmed ultrasound findings progressed. CONCLUSIONS: Using ultrasound to detect the parotid gland's location before thread lifting might reduce the chance of parotid duct injury. Identifying immediate parotid duct or gland injury with ultrasound can help to act quickly for delayed pain or swelling and reduce the likelihood of additional complications.

Salivary gland 18F-FDG-PET/CT uptake patterns in Sjögren's syndrome and giant cell arteritis patients.

OBJECTIVES: Wide variety in salivary gland 18F-FDG-uptake is observed in the general population. A general consensus about the usefulness of 18F-FDG-PET/CT to detect salivary gland inflammatory conditions, such as in primary Sjögren's syndrome (pSS), is not yet clear. This study aimed to investigate whether there are differences in uptake of 18F-FDG in salivary glands among two autoimmune groups [pSS, giant cell arteritis (GCA)] and a non-autoimmune group (lung cancer). METHODS: PSS patients aged ≥50 years who underwent 18F-FDG-PET/CT were included and age-matched with GCA patients and a non-autoimmune control group (lung cancer patients). Scans were visually evaluated and quantitative analysis was performed by measuring standardised uptake values (SUV) within salivary glands and lacrimal glands. For GCA patients, arteries in the vicinity of the parotid and submandibular gland were assessed for positivity. RESULTS: PSS patients did not show increased 18F-FDG-uptake in the parotid or submandibular gland, compared to the other two groups. For the tubarial gland, significantly higher SUVmax was found in the pSS patient group. Interestingly, GCA patients had significantly higher SUVmax in the submandibular gland than the other two groups. Visual 18F-FDG-positivity of cranial arteries related to the parotid and submandibular glands was associated with significantly higher SUVmax in salivary glands of GCA patients. CONCLUSIONS: Although 18F-FDG-uptake was not increased in parotid and submandibular glands of pSS patients, increased 18F-FDG-uptake in tubarial glands of pSS patients might indicate a role for these glands in pSS. Furthermore, parotid and submandibular glands may be affected by local vasculitis in GCA.

Nuts and bolts of salivary gland pathology in primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is a chronic, systemic, inflammatory autoimmune disease characterised by lymphocyte proliferation and progressive damage to exocrine glands. Salivary gland histopathology based on salivary gland biopsy is relevant for the diagnosis of pSS and therefore broadly applied in clinical practice. Tissue can be obtained from labial salivary glands (LSG) biopsy or from major salivary glands (MSG) biopsy, namely the parotid; in this latter scenario, the procedure can be either an open surgical biopsy or a US guided core needle biopsy.In this review we will: i) present the histopathological findings that may be encountered by pathologists on biopsies from pSS patients; ii) discuss the advantages and disadvantages of the surgical and/or imaging guided procedures to obtain tissues from LSG or MSG; iii) describe the histopathological features of lymphoma of MSG in pSS patients.

Longitudinal evaluation of major salivary gland functioning in Sjögren's disease patients in a prospective standard-of-care cohort.

OBJECTIVES: To evaluate changes in major salivary gland functioning over time using salivary gland ultrasonography (SGUS), salivary flow measurements (sialometry), and patient-reported outcome measures (PROMs) in patients diagnosed with primary Sjögren's disease (SjD). METHODS: Consecutive outpatients from the ongoing prospective REgistry of Sjögren Syndrome LongiTudinal (RESULT) cohort, all fulfilling the ACR-EULAR classification criteria for SjD, were included. SGUS images assessed with the Hocevar and OMERACT scoring system, unstimulated and stimulated whole saliva (UWS/SWS), unstimulated and stimulated submandibular/sublingual saliva (uSMSLS/sSMSLS) and parotid saliva, EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) general dryness, oral dryness, and Xerostomia Inventory were assessed at baseline (BL), 2-year (Y2) and 5-year (Y5) follow-up. RESULTS: In total, BL and Y2 data were available for 253 patients and 75 patients had already reached Y5. At group level, SGUS Hocevar (i.e., mean±SD: 22±10 at BL, 22±10 at Y2 and 23±10 at Y5), OMERACT scores, UWS, SWS and PROMs remained stable over time (all p>0.05). Slightly decreased uSMSLS (p=0.025) and sSMSLS (p=0.004) were observed at Y5. At individual patient level, a similar proportion showed an increase or decrease of ≥25% for Hocevar, UWS and SWS. At baseline, poor associations were observed between SGUS and PROMs and fair associations between sialometry and PROMs. Over time, changes in objective assessments did not correlate with changes in PROMs. CONCLUSIONS: Overall, major salivary gland functioning assessed with SGUS, sialometry and PROMs did not change significantly up to 5 years of follow-up in a standard-of-care cohort of SjD patients from daily clinical practice.

Uncommon Coexistence of Pleomorphic Adenoma and Warthin's Tumor in a Painfully Swollen Left Parotid Gland: A Surgical Case Report.

BACKGROUND Benign pleomorphic adenoma is the most common primary tumor of the salivary glands and mainly arises in the parotid gland. Warthin's tumor, or papillary cystadenoma lymphomatosum, represents <30% of benign parotid tumors. The simultaneous occurrence of multiple parotid tumors is rarely described - depending on the corresponding histology (different/identical), the time of their occurrence (synchronous/metachronous), as well as their location (unilateral/bilateral), multiple parotid tumors can be further sub-classified. CASE REPORT We describe the case of a 54-year-old female patient with progressive and painful swelling of the left parotid gland for the last 6 months. During extra-oral examination, a bulging, displaceable mass of approximately 3 cm was determined. A subsequent MRI (magnetic resonance imaging) examination revealed a multifocal lesion but failed to provide a decisive clue as to the tumor entity of the lesion, and a lateral (superficial) parotidectomy was performed. Postoperative histomorphological interpretation allowed the final pathological diagnosis of synchronous, unilateral occurrence of a pleomorphic adenoma as well as a Warthin's tumor. CONCLUSIONS This report presents a rare case of synchronous unilateral parotid tumors and supports that benign pleomorphic adenoma and Warthin's tumor are the most common associations. Since clinical examination, MRI imaging, and even cytological assessment could be misleading in the detection of synchronous ipsilateral multiple parotid gland tumors, our report also highlights the importance of timely and accurate diagnosis with histopathology to plan surgery and to exclude malignant transformation, which is a rare but important association with both types of primary salivary gland tumor.