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.

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.

BACKGROUND: To develop a deep learning(DL) model utilizing ultrasound images, and evaluate its efficacy in distinguishing between benign and malignant parotid tumors (PTs), as well as its practicality in assisting clinicians with accurate diagnosis.
METHODS: A total of 2211 ultrasound images of 980 pathologically confirmed PTs (Training set: n = 721; Validation set: n = 82; Internal-test set: n = 89; External-test set: n = 88) from 907 patients were retrospectively included in this study. The optimal model was selected and the diagnostic performance evaluation is conducted by utilizing the area under curve (AUC) of the receiver-operating characteristic(ROC) based on five different DL networks constructed at varying depths. Furthermore, a comparison of different seniority radiologists was made in the presence of the optimal auxiliary diagnosis model. Additionally, the diagnostic confusion matrix of the optimal model was calculated, and an analysis and summary of misjudged cases\' characteristics were conducted.
RESULTS: The Resnet18 demonstrated superior diagnostic performance, with an AUC value of 0.947, accuracy of 88.5%, sensitivity of 78.2%, and specificity of 92.7% in internal-test set, and with an AUC value of 0.925, accuracy of 89.8%, sensitivity of 83.3%, and specificity of 90.6% in external-test set. The PTs were subjectively assessed twice by six radiologists, both with and without the assisted of the model. With the assisted of the model, both junior and senior radiologists demonstrated enhanced diagnostic performance. In the internal-test set, there was an increase in AUC values by 0.062 and 0.082 for junior radiologists respectively, while senior radiologists experienced an improvement of 0.066 and 0.106 in their respective AUC values.
CONCLUSIONS: The DL model based on ultrasound images demonstrates exceptional capability in distinguishing between benign and malignant PTs, thereby assisting radiologists of varying expertise levels to achieve heightened diagnostic performance, and serve as a noninvasive imaging adjunct diagnostic method for clinical purposes.

BACKGROUND: Basal cell adenoma (BCA) is a rare benign tumor within the salivary glands. Basal cell adenocarcinoma (BCAC), the malignant counterpart of BCA, is also an exceedingly rare tumor with very limited clinical studies conducted. This study aims to investigate the clinical characteristics, demographics, and surgical outcomes of patients diagnosed with BCA and BCAC within the parotid gland.
METHODS: A retrospective analysis from May 2003 to August 2023 was performed for all patients undergoing parotidectomy for masses. Retrospective data on gender, age, tumor characteristics, and outcomes were collected. Surgical approaches, including negative margin attainment, capsule removal, and histological diagnosis, were also detailed.
RESULTS: The study included 1268 patients who underwent parotidectomy, resulting in 81 cases of BCA and 7 cases of BCAC. BCA patients, with a mean age of 55.1 years, showed diverse age distribution and predominantly presented in the 50s. In BCAC cases, seven female patients exhibited a predominant location in the deep lobes. FNA revealed BCAC in three out of seven cases, and subsequent parotidectomy was performed, resulting in no observed recurrences or metastases.
CONCLUSIONS: This study reports the largest number of BCA cases from a single institution and provides comprehensive insights into the demographics, tumor characteristics, and clinical outcomes of both BCA and BCAC. Although further research should be conducted, based on clinical follow-up results, appropriately including the capsule in the tumor excision indicates favorable outcomes, especially when the tumor size is not large.

OBJECTIVE: To assess the performance of diffusion-relaxation correlation spectrum imaging (DR-CSI) in the characterization of parotid gland tumors.
METHODS: Twenty-five pleomorphic adenomas (PA) patients, 9 Warthin\'s tumors (WT) patients and 7 malignant tumors (MT) patients were prospectively recruited. DR-CSI (7 b-values combined with 5 TEs, totally 35 diffusion-weighted images) was scanned for pre-treatment assessment. Diffusion (D)-T2 signal spectrum summating all voxels were built for each patient, characterized by D-axis with range 0∼5 × 10-3 mm2/s, and T2-axis with range 0∼300ms. With boundaries of 0.5 and 2.5 × 10-3 mm2/s for D, all spectra were divided into three compartments labeled A (low D), B (mediate D) and C (high D). Volume fractions acquired from each compartment (VA, VB, VC) were compared among PA, WT and MT. Diagnostic performance was assessed using receiver operating characteristic analysis and area under the curve (AUC).
RESULTS: Each subtype of parotid tumors had their specific D-T2 spectrum. PA showed significantly lower VA (8.85 ± 4.77% vs 20.68 ± 10.85%), higher VB (63.40 ± 8.18% vs 43.05 ± 7.16%), and lower VC (27.75 ± 8.51% vs 36.27 ± 11.09) than WT (all p<0.05). VB showed optimal diagnostic performance (AUC 0.969, sensitivity 92.00%, specificity 100.00%). MT showed significantly higher VA (21.23 ± 12.36%), lower VB (37.09 ± 6.43%), and higher VC (41.68 ± 13.72%) than PA (all p<0.05). Similarly, VB showed optimal diagnostic performance (AUC 0.994, sensitivity 96.00%, specificity 100.00%). No significant difference of VA, VB and VC was found between WT and MT.
CONCLUSIONS: DR-CSI might be a promising and non-invasive way for characterizing parotid gland tumors.

The research purpose is to review the surgical approach and evaluate the results in adult patients with head and neck sarcomas. The histopathology varied, including two leiomyosarcomas, six malignant fibrous histiocytomas, two malignant peripheral nerve sheath tumors, four dermatofibrosarcomas protuberans, three osteosarcomas, two angiosarcomas, one liposarcoma, one Ewing sarcoma, one synovial sarcoma, two unclassified/non-differentiated sarcomas and one solitary fibrous tumor. Surgical resection included maxillectomy, mandibulectomy, craniectomy, parotidectomy, scalp resection, face skin resection and laminectomy. The reconstruction was performed with one rectus abdominis flap, four radial forearm flaps, two latissimus dorsi flaps, two vascularized fibula flaps, two pectoralis major myocutaneous flaps, two trapezius flaps, two temporalis flaps, seven scalp flaps and two nasolabial flaps. The total patient number was 24. The hospitalization was uncomplicated, followed by postoperative radiotherapy in the majority of cases. In a mean 15-year follow-up period, 11 patients are still alive and disease-free. There were four recurrences treated with palliative radiotherapy. The surgical approach for head and neck sarcomas, including the achievement of a functionally acceptable result by organ sparing techniques, remains challenging. Wide resection combined with the appropriate reconstruction, particularly with microsurgical techniques, and followed by adjuvant radiotherapy or chemotherapy offer improved prognosis and quality of life.

OBJECTIVE: To determine the occult nodal disease rate and whether elective regional lymph node dissection (RLND) confers any 10-year overall survival (OS) in cN0 intermediate-grade mucoepidermoid carcinoma (MEC) of the parotid gland.
METHODS: The National Cancer Database was reviewed from 2004 to 2016 on adults with cT1-4aN0M0 intermediate-grade parotid MEC undergoing resection with/without RLND. Comparisons between patients with and without RLND were made. Occult nodal rate and 10-year overall survival (OS) were determined.
RESULTS: Out of 898 included patients with cN0 intermediate grade parotid MEC undergoing elective RLND, the occult nodal rate was 7.6%. This was significantly different from low-grade (3.9%) and high-grade (25.7%) cN0 disease. When stratified by pT-classification, marginal differences were identified between low-grade and intermediate-grade tumors, whereas high-grade tumors demonstrated increased occult nodal disease with low T-stage (pT1-pT2, 20.4% vs. 5.1%) and high T-stage (pT3-pT4a, 32.1% vs. 17.6%). Patients undergoing elective RLND were more often treated at an academic facility (53.8% vs. 41.2%), had higher pT3-pT4 tumors (19.2% vs. 10.4%), and more frequently underwent total/radical parotidectomy (46.0% vs. 29.9%) with adjuvant radiation therapy (53.8% vs. 41.0%) Cox-proportional hazard modeling did not identify RLND, regardless if stratified by nodal yield or pT-classification, nor nodal positivity as significant predictors of 10-year OS.
CONCLUSIONS: The occult nodal disease in intermediate-grade parotid MEC is low and similar to low-grade. Elective RLND may have a limited impact on OS, though its effect on locoregional control remains unknown.
METHODS: III.

OBJECTIVE: To investigate the diagnostic performance of histogram features of diffusion parameters in characterizating parotid gland tumors.
METHODS: 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.

OBJECTIVE: This study aimed to evaluate the feasibility and outcomes of mixed reality combined with surgical navigation (MRSN) in the resection of parotid micro- and mini-tumors.
METHODS: Eighteen patients who underwent parotid tumor resection between December 2020 and November 2022 were included. Six patients were enrolled in MRSN group, and the surgeons performed the surgery with the help of MRSN technology. The surgical procedures include virtual planning, data transfer between mixed reality and surgical navigation, tumor localization and resection assisted by surgical navigation under mixed reality environment. Twelve patients were enrolled in control group, and intraoperative tumor localization and resection were performed according to the experience of the surgeon. Total surgery time and intraoperative bleeding were recorded. Perioperative complications were recorded during follow-up.
RESULTS: The mean surgery time of MRSN group (76.7 ± 14.0 min) and control group (65.4 ± 21.3 min) showed no significant difference (p = 0.220), so did the intraoperative bleeding of MRSN group (16.0 ± 8.0 mL) and control group (16.7 ± 6.6 mL) (p = 0.825). None of the patient in MRSN group underwent any complication, although one patient in control group suffered temporary facial paralysis. The mean deviation between the virtually marked and the intraoperative actual outermost point of tumor was 3.03 ± 0.83 mm.
CONCLUSIONS: MRSN technology can realize real-time three-dimensional visualization of the tumor, and it has the potential of enhancing the safety and accuracy of resection of micro- and mini-tumors of parotid gland.
METHODS: 4 Laryngoscope, 134:1670-1678, 2024.

Objective: To analyze the temperature difference of benign and malignant parotid gland tumors in preoperative infrared thermography (IRT), and to provide the basis for predicting tumor properties. Methods: The clinical data of 98 patients with parotid gland tumor admitted to the Department of Oral and maxillofacial Surgery of the First Affiliated Hospital of Bengbu Medical College, from May 2021 to April 2023 were retrospectively analyzed. There were 61 males and 37 females, aged (51.1±16.0) years (10-86 years). In addition to routine examination, the temperature difference between the lesion site of parotid gland and the contralateral mirror area was measured by infrared thermal imager in all patients one day before surgery. The maximum diameter (dmax) and location of the tumor (deep or superficial lobe) were recorded according to preoperative clinical examination and imaging examinations such as CT and ultrasound. The patients were divided into three groups by tumor size: dmax≤2 cm, 2 cm4 cm. The patients were also divided into different groups: deep lobe group and superficial lobe group (according to the tumor location), benign group and malignant group (according to postoperative pathological results). The relationship between temperature difference, pathology, size and location was analyzed. Results: There were 79 cases in the benign group and 19 cases in the malignant group. The temperature difference of the healthy and affected side in the malignant group [(1.73±0.21) ℃] was significantly higher than that in the benign group [(0.73±0.32) ℃] (t=16.70, P<0.001). There was no significant difference in temperature difference between the healthy and affected sides of tumors with different diameters (P>0.05). The temperature difference of healthy and affected side of tumor in superficial lobe [(0.97±0.50) ℃] was significantly higher than that in deep lobe [(0.67±0.44) ℃] (t=2.24, P=0.028). Conclusions: The difference of temperature difference between benign and malignant parotid gland tumors detected by IRT is statistically significant, which can be used to predict tumor properties, and has certain clinical application value.
目的： 分析腮腺良恶性肿瘤患者术前红外热成像（infrared thermography，IRT）图的健患侧温差特点，为IRT预测肿瘤性质提供依据。 方法： 回顾性分析2021年5月至2023年4月，蚌埠医学院第一附属医院口腔颌面外科收治入院的98例腮腺肿瘤患者的临床资料，其中男性61例，女性37例，年龄（51.1±16.0）岁（10~86岁）。所有患者除常规检查外均于术前1 d用IRT仪测量腮腺病变部位与对侧镜像区域的温差，并根据术前临床检查和CT、超声等影像学检查记录肿瘤最大径、发生位置（深叶或浅叶），根据肿瘤最大径分为≤2 cm、>2 cm且≤4 cm、>4 cm共3组；根据发生位置分为深叶组和浅叶组；根据术后病理结果分为良性组和恶性组。分析温差大小与肿瘤性质、大小及位置的关系。 结果： 良性组79例，恶性组19例，恶性组的健患侧温差［（1.73±0.21）℃］显著高于良性组［（0.73±0.32）℃］（t=16.70，P<0.001）。不同最大径的肿瘤组间健患侧温差的差异无统计学意义（P>0.05）。浅叶组肿瘤健患侧温差［（0.97±0.50）℃］显著高于深叶组［（0.67±0.44）℃］（t=2.24，P=0.028）。 结论： IRT检测出的腮腺良恶性肿瘤的健患侧温差的差异有统计学意义，可根据温差大小进行肿瘤性质预测，有一定临床应用价值。.