Feasibility and safety of preauricular incision for extracapsular dissection in benign parotid tumors.

PURPOSE: Parotidectomy techniques continuously evolve to improve outcomes while minimizing morbidity. This study investigates the rationale behind developing and evaluating the feasibility and safety of extracapsular dissection (ECD) via preauricular incision for benign parotid tumors in the anterior or superior part of the parotid gland. METHODS: The preauricular approach is developed to address the increasing demand for minimally invasive techniques that prioritize both functional and aesthetic outcomes. Minimizing visible scarring and preserving facial nerve function offers a compelling solution for patients seeking optimal cosmetic results without compromising surgical efficacy. Patient assessments included cosmetic contentment, functional repercussions, and disease management throughout the follow-up. RESULTS: Eight patients underwent ECD via the preauricular approach, demonstrating favorable outcomes with preserved facial nerve function and minimal complications. CONCLUSION: This study highlights the potential of the preauricular approach as a preferred option for managing benign parotid tumors in the anterior or superior parotid region, emphasizing aesthetic outcomes and preserving gland function. LEVEL OF EVIDENCE: IV.

Ultrasonographic study and anatomical guidelines for botulinum neurotoxin injection into the parotid gland.

Benign enlargement of the parotid gland hypertrophy results in a bulky lateral facial contour and esthetic appearance. This study aimed to determine the depth from the skin surface to the parotid fascia, which encompasses the parotid gland. The anatomical properties of the parotid glands were evaluated in 40 patients using ultrasonography. An up-to-date understanding of the localization of botulinum neurotoxin (BoNT) injection based on anatomy could lead to better localization of the injection into the parotid gland through morphological measurements using data previously published from cadaveric studies. Measurement using the otobasion inferius as a landmark revealed parotideomasseteric fascia thickness averaging 4-6 mm from the skin surface, with the parotid gland extending approximately 15 mm anteriorly. Analysis showed a 3-7 mm thickness range, indicating an optimal injection depth for safety and efficacy in BoNT procedures. Utilizing the otobasion inferius as an anatomical landmark offers a practical approach for measuring parotideomasseteric fascia thickness, addressing cadaveric study limitations. These guidelines aim to maximize the effects of BoNT therapy, which can be useful in clinical settings, by minimizing its deleterious effects.

Follicular dendritic cell sarcoma involving the parotid gland with expression of the melanocytic marker PRAME.

Follicular dendritic cell sarcoma is a rare mesenchymal neoplasm arising from follicular dendritic cells (FDC) of lymphoid follicles. While the majority of FDC sarcoma cases arise within lymph nodes, approximately 30% manifest in extranodal sites. Only 4 prior occurrences of intra-parotid FDC sarcomas have been documented. We are reporting a rare case of FDC of the parotid gland in a 65-year-old male with a questionable history of B-cell lymphoma. The patient underwent a right total parotidectomy and bilateral neck dissection. A diagnosis of follicular dendritic cell (FDC) sarcoma was made, with one positive intra-parotid node. The malignant cells expressed the characteristic markers for FDC sarcoma but with positivity of the melanocytic marker PRAME. This is a case of FDC sarcoma with an unusual extranodal localization in the parotid gland. Immunohistochemistry was useful in making a diagnosis although the positivity for the melanocytic marker PRAME was unusual and unreported before.

The comparative morphology of the oral cavity glands in captive South African painted dogs (Lycaon pictus pictus) and captive fennec foxes (Vulpes zerda) (Carnivora: Canidae).

BACKGROUND: The African painted dog is classified as a relic canid lineage, inhabiting areas south of the Sahara. The fennec fox is the smallest member of the Canidae family, found in the Arabian Peninsula and northern Sahara. METHODS: The gross anatomy and light microscopic examination of the oral cavity glands were studied in five adult captive South African painted dogs and five adult captive fennec foxes from the Wroclaw Zoological Garden, Poland. In this research, the zygomatic gland, monostomatic sublingual gland, polystomatic sublingual gland, mandibular gland, and parotid gland were examined for their topography, morphometry, histology, and histochemistry using hematoxylin and eosin, azan trichrome, mucicarmine, PAS, AB pH 1.0, AB pH 2.5, AB pH 2.5 PAS, and HID. RESULTS: We found that the parotid glands were consistently the largest, followed by the mandibular and sublingual glands (both monostomatic and polystomatic). The zygomatic gland was the smallest in both South African painted dogs and fennec foxes. Interestingly, there were noticeable differences in the size, shape, and even composition of the secretory products between the two species. The zygomatic and polystomatic sublingual glands in the South African painted dog and the fennec fox were complex branched tubular. In the South African painted dog, the monostomatic gland was a branched tubular compound gland, while in the fennec fox, it was a branched tubuloalveolar compound gland. The mandibular gland in hunting dogs was a branched tubular compound gland, while in the fennec fox a branched tubuloalveolar compound gland. The parotid gland in the fennec fox was a branched acinar compound gland, whereas in the painted dog was a branched tubuloacinar. CONCLUSIONS: The basic structure of their glands is similar to that of other terrestrial carnivores, indicating a shared evolutionary origin and function. However, differences in the composition of their secretory products can reflect adaptations to their specific diets. This research provides valuable insights for veterinary medicine and underscores the importance of further studies. By analyzing wild canid populations and including a broader range of species with diverse diets, we could gain a deeper understanding of how diet influences salivary gland morphology within the Canidae.

New 3-D Technologies in Salivary Gland Surgery: The Exoscope-Assisted Surgery for Treatment of Benign Tumors of Parotid Gland.

New technologies are increasingly widespread in medical practice. Particularly, the 3D view is considered among the most useful innovations for surgery. It allows the operator to reconstruct the patient's anatomy in his own mind, going beyond his personal imagination. In the last few years, a new facility has been experienced, it's the Exoscopy. Exoscopy is a magnified vision system, similar to Microscopy, but which also allows a tridimensional vision of the surgical anatomy. Despite Exoscopy having been used for years in Neurosurgery, it has been just rarely described in parotid surgery. We intend to report our experience with Exoscope Aesculap AEOS used to remove benign tumors of the parotid gland. We treated 14 patients with benign tumors of the parotid gland, since September 2023 to November 2023. Each surgery was conducted by the same expert surgeon which also reported his experience about intra-operative complications (as bleeding) in comparison to the traditional procedure without Exoscope. We evaluated the learning curve of Exoscope-Assisted Parotid Surgery comparing, among them, the operative times of the same procedures performed in chronological order. Each patient underwent the same follow-up which included three checks at one month, three months and six months. The follow-up was especially about the evaluation of palsy of the VII C.N. which was assessed through House-Brackmann score (H-B score). The results of our experience reports that the Exoscope is a useful tool for parotid gland surgery. It allows an excellent visualization of the facial nerve main trunk and its branches. Although the first procedures presented longer times in comparison to traditional surgery, the progressive reduction of the operative times demonstrates that the learning curve of Exoscopy is very fast. Certainly, more experience is required for the full introduction of Exoscopy in surgery practice of parotid gland but, now, its potentialities are highly exciting.

Revealing Enigma in Parotid Gland: Venolymphoma-A Rare Case Report.

Venolymphoma (VL) is a benign condition of oral cavity, but it is misdiagnosed as pleomorphic adenoma. Exact diagnosis can be made only after histopathological examination. In this report the author has presented a case of a 45-year-old male patient with VL of right parotid which was operated. The treatment indicated was complete excision of the lesion, which showed an excellent prognosis with low recurrence rate.

Parotid gland MALT lymphoma with amyloid deposition, challenges in preoperative diagnosis: A case report.

Mucosa-associated lymphoid tissue (MALT) lymphoma commonly arises from chronic inflammation or autoimmune diseases, such as Sjögren syndrome (SjS). Although rare, amyloid deposition in MALT lymphoma has been reported. We present a rare case of parotid gland MALT lymphoma in a 49-year-old woman, in whom preoperative diagnosis was challenging due to atypical imaging findings resulting from amyloid deposits. MRI showed T2-hypointense and T1-iso- to slightly hyperintense masses in the left parotid gland and right sublingual gland, with predominant marginal contrast enhancement and no significant diffusion restriction. Additionally, atrophy and fatty replacement of the parenchyma were noted in bilateral parotid glands, suggesting SjS. Left superficial parotidectomy was performed and pathological findings confirmed MALT lymphoma with extensive amyloid deposition. Histopathological findings of the resected parotid gland parenchyma also suggested SjS. MALT lymphoma should be considered in the differential diagnosis of multiple salivary gland masses in patients with suspected SjS. If MRI reveals atypical imaging findings for malignant lymphoma, particularly T2-hypointensity with no significant diffusion restriction, the possibility of amyloid deposition in MALT lymphoma should be considered.

Keratocystoma of the Parotid Gland: A Rare Case and Review of the Literature.

Keratocystoma of the parotid gland is a rare benign salivary gland tumor. In 2022, the World Health Organization added keratocystoma to the classification of benign parotid tumors. Recently, our hospital encountered a case involving a 2-year-old child, making this the youngest patient reported to date. We excised part of the parotid gland and lesion under general anesthesia while preserving the facial nerve. There was no local recurrence during the 1-year follow-up period after surgery. Despite its rarity, it is essential to consider the possibility of keratocystoma and distinguish it from other benign neoplastic lesions of the parotid gland.

Surgical management of basal cell adenoma of the parotid gland: A case report and review of the literature.

INTRODUCTION AND IMPORTANCE: Basal cell adenoma (BCA) is a rare, benign tumor of the salivary gland. It has distinct histologic features that are different from mixed tumors of the salivary gland. Often times, it occurs in the parotid gland. Usually it appears as a hard, slowly growing, asymptomatic lump that may exist for years prior to treatment. Pathologically, BCA tumors demonstrate a monomorphic basaloid cell population devoid of myxochondroid components. This rather uncommon tumor's clinical appearance, pathological characteristics, differential diagnosis, and available treatments have been briefly described. CASE PRESENTATION: A 52-year-old female patient presented with a longstanding, gradual facial asymmetry that resulted from a mass of parotid region. She had no other symptoms. Radiology and cytology test results were suggestive of a benign salivary gland tumor of the parotid gland. A superficial parotidectomy was successfully done with a preservation of the facial nerve. Histopathology reported concluded the diagnosis of BCA trabecular subtype. During the 12-month follow-up period, the tumor did not recur, and there was no postoperative impairment of the facial nerve. CLINICAL DISCUSSION: Imaging studies, including CT scans and MRI, are helpful in determining the tumor's size, location, and relationship to adjacent structures. The definitive diagnosis is achieved through histopathology. This clinically asymptomatic mass requires early recognition, a prompt therapeutic intervention and long-term follow-up. CONCLUSION: As clinicians, it is critical that we have a thorough understanding of clinicopathology in terms of clinical presentation, pathology, diagnosis, treatment, and prognosis of this rare tumor.

Anatomical study and clinical outcomes of endoscopic transoral surgery for benign salivary gland tumors in the parapharyngeal space.

The existing literature provides little insight into the efficacy of transoral endoscopy in exposing benign tumors originating from salivary glands in the parapharyngeal space at the parotid gland base and resecting part of the deep lobe with a safe margin. This study aims to investigate the efficacy of the endoscopic transoral approach for the visualization and resection of such tumors. Through transoral endoscopic cadaveric dissections and surgical procedures, we examined the anatomical structures of the parapharyngeal space and the deep lobe of the parotid gland, identifying key anatomical landmarks. We conducted a retrospective analysis of 19 patients with benign salivary gland-derived tumors in the parapharyngeal space who underwent transoral endoscopic resection. Intraoperative visualization of the tumor pedicle and the deep lobe of the parotid gland was successfully achieved in all cases, allowing for resection with safe margins. During a median follow-up period of 54.0 months, imaging revealed no signs of recurrence. Endoscopic transoral approach provides effective visualization of the deep lobe of the parotid gland and the medial portion of the parotid bed from the parapharyngeal space. Benign tumors of salivary gland-derived in this area can be well exposed and safely resected with adequate margins.

Comprehensive Next Generation Sequencing Reveals that Purported Primary Squamous Cell Carcinomas of the Parotid Gland are Genetically Heterogeneous.

Squamous cell carcinoma (SCC) is one of the most common malignancies involving the parotid gland, but it has been recognized that the vast majority of parotid SCC represents metastases, especially from the ipsilateral facial skin. Bona fide primary SCC of the parotid is so rare that it is unclear whether it truly exists at all. We sought to molecularly characterize cases diagnosed as primary parotid gland SCC to see if they possess a unique genetic makeup.We identified cases in our archives which had been diagnosed as primary SCC of the parotid gland. In all cases, metastatic disease was excluded by a thorough history and physical examination. Cases with histologic evidence of a precursor neoplasm (e.g., carcinoma ex-pleomorphic adenoma) were also excluded. Targeted next-generation sequencing (NGS) was attempted on all cases.Six cases diagnosed as primary parotid SCC were identified, arising in 4 males and 2 females ranging from 8 to 73 years (mean, 51.8 years). All cases exhibited keratinization and unequivocal invasion. Four of 6 appeared to be arising from cystically dilated ducts. Five of 6 exhibited well-developed cellular atypia; the remaining case, while cytologically bland, demonstrated perineural invasion. Targeted NGS was successful in 5 of 6 cases. Two SCC harbored several mutations in a mutational profile reminiscent of SCCs seen in other organs. One case harbored YAP1::MAML2, a fusion previously reported in porocarcinoma and other neoplasms. One case harbored IRF2BP2::RUNX2, and presumably represents keratocystoma or SCC ex-keratocystoma. Finally, one case an increase of C > T mutations consistent with ultraviolet damage, suggesting that this case represented a cryptic metastasis from cutaneous SCC.Our analysis did not confirm a unifying genetic signature for purported primary parotid SCC. Indeed, our findings suggest that true primary parotid gland SCC is even rarer than already believed. In our 5 cases with results, NGS findings demonstrated that one was likely a keratocystoma, one a cryptic metastasis from a cutaneous SCC, and one a porocarcinoma, either metastatic or primary. The two remaining cases had complex genotypes reminiscent of SCCs from other sites. This may be the signature of genuine parotid primary SCC, but metastasis from an SCC from another organ cannot be excluded. Accordingly, a diagnosis of primary parotid gland SCC should be viewed with skepticism.

Revision parotidectomy - analysis of indications for the procedure and treatment results based on 10 years of follow-up in a single center.

<b>Introduction:</b> Surgical removal of recurrent parotid gland tumours is the first-line treatment but presents an increased risk of facial nerve injury and a considerable re-recurrence failure rate.<b>Aim:</b> Identification of individuals exposed to a higher risk of re-procedure, raising awareness in the preoperative setting, and proposing an optimal follow-up.<b>Methods:</b> The retrospective review included 72 patients treated with revision surgery in a single centre. The demographics, clinicopathologic variables, and operative details were analysed.<b>Results:</b> Recurrent pleomorphic adenoma (PA) was the main reason for reoperation (66.7%), followed by new monomorphic adenoma (13.9%), resection extension (12.5%), and malignancy recurrence (6.9%). Time to revision surgery was on average 68.6 months and was the shortest for extended resection cases (average 1.9 months). The period was substantially longer in recurrent PA (90.8 months). The final facial nerve function according to the House-Brackmann scale (HBS) decreased in 37% of patients after reoperation. The number of recurrences per patient ranged from one in 61% of cases to eight in a solitary case.<b>Conclusions:</b> The rate of revision parotid surgery was 8.4%. Negative margins at the first resection were not of protective significance. Recurrent PA was the main cause of revision surgery and over one-third of this cohort had a subsequent relapse. As many as 37% of patients experienced a decrease in facial nerve function following revision surgery.

A presentation of basal cell adenoma: a case report.

BACKGROUND: While statistically rare in comparison to other head and neck tumours, parotid gland swellings are often encountered in clinical practice where one of the primary goals of examination becomes distinction between benign and malignant lesions. Hallmarks of malignancy are characterized by a female preponderance, history of radiation exposure, a positive family history, and clinical features like heterogenous consistency, fixity to skin/underlying tissues and involvement of facial nerve. CASE PRESENTATION: Here we present a case of parotid swelling in a 72-year old gentleman from south India that had a curious amalgamation of both benign and malignant features. CONCLUSIONS: While benign, the risk of malignant transformation and rare multicentric occurrence indicates a need to keep basal cell adenoma in mind in case of parotid swellings and their surgical management.

Imaging of the Major Salivary Glands in Rheumatic Disease.

Salivary gland involvement is a common feature of rheumatologic disease. The authors review the anatomy of the major salivary glands and the uses of imaging modalities such as ultrasound, MRI, computed tomography, sialography, and scintigraphy in evaluating the major salivary glands in rheumatologic disease.

Ultrasonography-Guided Fine Needle Aspiration Cytology Versus Histopathology: Diagnostic Consistency in Salivary Gland Neoplasms.

Introduction Salivary gland lesions include a diverse range of histological types and biological behaviors, making accurate diagnosis and effective treatment challenging for specialists. Fine needle aspiration cytology (FNAC) plays a significant role in making preoperative diagnoses and further plans of surgery. In differentiating malignant from benign salivary gland tumors, the diagnostic accuracy of fine needle aspiration cytology (FNAC) is high. However, the final diagnosis is histopathological. The aim of this study is to correlate cytological and histopathological interpretations in salivary gland lesions. Materials and method Thirty patients were included in this study, all of them were diagnosed with salivary gland swellings and operated on in the ear, nose, and throat (ENT) department of Mata Gujri Memorial (MGM) Medical College, Kishanganj, in the northeastern region of India, between December 2020 and November 2022. Ultrasonography (USG) and computed tomography (CT) scans were performed in each case, and FNAC was done to make a preoperative diagnosis. After surgery, specimens were collected for histopathological examination. A correlation was then made between the findings of the preoperative cytological examination and the results of the postoperative histopathological examination. The comparison was performed using a 2×2 table, and the analysis of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was carried out using Microsoft Excel (Microsoft Corp., Redmond, WA) and SPSS software (IBM SPSS Statistics, Armonk, NY). Results An equal number of male and female samples were included in the study, in which parotid involvement was predominant (60%). On FNAC, 53% of parotid gland tumors were found to be benign, whereas only 23.3% of submandibular gland tumors were benign. Pleomorphic adenoma was the most common finding. In the present study, the sensitivity, specificity, positive predictive value, and negative predictive value of USG-guided FNAC, compared to the gold standard histopathology, were 96%, 33.3%, 92.3%, and 50%, respectively. The diagnostic accuracy was found to be 89.3%. Conclusion The findings of this study suggest that FNAC is a reliable technique for the preoperative diagnosis of salivary gland tumors, as it is minimally invasive and offers valuable diagnostic information. An accurate cytological diagnosis can help avoid unnecessary surgery.

Erysipelas-Like Carcinoma of the Parotid Gland With Cutaneous Metastasis to the Neck Requiring Tracheostomy: A Case Report.

We present the case of a 71-year-old man who, after undergoing postoperative radiotherapy for epithelial carcinoma, developed progressively enlarging erythema. Initially, the condition resembled radiation dermatitis or erysipelas, and topical steroids and antibacterial agents were administered without success. A biopsy was performed for further evaluation, revealing a cutaneous invasion of parotid carcinoma. The lesion continued to enlarge, leading to dysphagia and ultimately necessitating a tracheostomy.

Metastatic malignancies in the parotid gland: A retrospective study.

The aim of this study was to compare treatment modalities, pathological and clinical characteristics, and outcomes in patients with metastasis in a parotid gland. The medical records of 34 patients who received treatment for metastasis in the parotid gland over a twenty-year period were evaluated. Patients with head and neck cutaneous squamous cell carcinoma (HNcSCC) metastasis were retrospectively reclassified using the P/N and N1S3 staging system. Patients with neck metastasis showed a significantly poorer prognosis (P = 0.025). Univariate analysis also revealed that extent of parotidectomy and type of neck dissection did not influence recurrence free survival (RFS) and overall survival (OS). When comparing the usefulness of the P/N and S1N3 staging systems, a positive correlation was observed between the P stage and the N1S3 stage in both RFS and OS. The extent of parotidectomy and concomitant neck dissection is still under discussion. Total parotidectomy and modified radical neck dissection did not improve RFS and OS. N1S3 is a less complex classification and possesses a higher predictive value when compared to the P/N staging system.

Machine learning-assisted diagnosis of parotid tumor by using contrast-enhanced CT imaging features.

PURPOSE: This study aims to develop a machine learning diagnostic model for parotid gland tumors based on preoperative contrast-enhanced CT imaging features to assist in clinical decision-making. MATERIALS AND METHODS: Clinical data and contrast-enhanced CT images of 144 patients with parotid gland tumors from the Peking University School of Stomatology Hospital, collected from January 2019 to December 2022, were gathered. The 3D slicer software was utilized to accurately annotate the tumor regions, followed by exploring the correlation between multiple preoperative contrast-enhanced CT imaging features and the benign or malignant nature of the tumor, as well as the type of benign tumor. A prediction model was constructed using the k-nearest neighbors (KNN) algorithm. RESULTS: Through feature selection, four key features-morphology, adjacent structure invasion, boundary, and suspicious cervical lymph node metastasis-were identified as crucial in preoperative discrimination between benign and malignant tumors. The KNN prediction model achieved an accuracy rate of 94.44 %. Additionally, six features including arterial phase CT value, age, delayed phase CT value, pre-contrast CT value, venous phase CT value, and gender, were also significant in the classification of benign tumors, with a KNN prediction model accuracy of 95.24 %. CONCLUSION: The machine learning model based on preoperative contrast-enhanced CT imaging features can effectively discriminate between benign and malignant parotid gland tumors and classify benign tumors, providing valuable reference information for clinicians.

Primary non-radiation induced angiosarcoma of the parotid with epithelioid morphology.

Angiosarcomas are rare, accounting for only 1-2% of sarcomas in the head and neck region. We present an extremely rare case of primary non-radiation-induced angiosarcoma of the parotid with epithelioid morphology which required a tertiary center second opinion for its histological characteristics. We discuss the presentation, imaging, diagnosis, characteristics, and pathway of this case. As parotid lumps are common, a surgical sieve is required to rule out other possible conditions. Early correct diagnosis is crucial in conditions such as angiosarcomas due to their quick metastatic potential.

Applying deep learning-based ensemble model to [18F]-FDG-PET-radiomic features for differentiating benign from malignant parotid gland diseases.

OBJECTIVES: To develop and identify machine learning (ML) models using pretreatment 2-deoxy-2-[18F]fluoro-D-glucose ([18F]-FDG)-positron emission tomography (PET)-based radiomic features to differentiate benign from malignant parotid gland diseases (PGDs). MATERIALS AND METHODS: This retrospective study included 62 patients with 63 PGDs who underwent pretreatment [18F]-FDG-PET/computed tomography (CT). The lesions were assigned to the training (n = 44) and testing (n = 19) cohorts. In total, 49 [18F]-FDG-PET-based radiomic features were utilized to differentiate benign from malignant PGDs using five different conventional ML algorithmic models (random forest, neural network, k-nearest neighbors, logistic regression, and support vector machine) and the deep learning (DL)-based ensemble ML model. In the training cohort, each conventional ML model was constructed using the five most important features selected by the recursive feature elimination method with the tenfold cross-validation and synthetic minority oversampling technique. The DL-based ensemble ML model was constructed using the five most important features of the bagging and multilayer stacking methods. The area under the receiver operating characteristic curves (AUCs) and accuracies were used to compare predictive performances. RESULTS: In total, 24 benign and 39 malignant PGDs were identified. Metabolic tumor volume and four GLSZM features (GLSZM_ZSE, GLSZM_SZE, GLSZM_GLNU, and GLSZM_ZSNU) were the five most important radiomic features. All five features except GLSZM_SZE were significantly higher in malignant PGDs than in benign ones (each p < 0.05). The DL-based ensemble ML model had the best performing classifier in the training and testing cohorts (AUC = 1.000, accuracy = 1.000 vs AUC = 0.976, accuracy = 0.947). CONCLUSIONS: The DL-based ensemble ML model using [18F]-FDG-PET-based radiomic features can be useful for differentiating benign from malignant PGDs. The DL-based ensemble ML model using [18F]-FDG-PET-based radiomic features can overcome the previously reported limitation of [18F]-FDG-PET/CT scan for differentiating benign from malignant PGDs. The DL-based ensemble ML approach using [18F]-FDG-PET-based radiomic features can provide useful information for managing PGD.