Incidentally found parotid gland lesion in 18F-FDG PET/CT for staging evaluation of patients with hepatocellular carcinoma: remote possibility of metastatic tumor or second primary salivary gland malignancy.

OBJECTIVES: We primarily aimed to evaluate whether parotid incidental lesion (PIL) in 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for staging evaluation of patients with hepatocellular carcinoma (HCC) would represent a possibility of extrahepatic metastasis or second primary malignancy (SPM). Additionally, we explored the incidence of PIL in HCC patients and examined any associated risk factors. METHODS: We retrospectively analyzed patients with HCC who underwent 18F-FDG PET/CT at our institution from 2010 to 2022. The pathological findings of PILs in HCC patients were investigated for confirmatory identification of the risk of HCC metastasis or SPM in parotid gland. Healthy controls received 18F-FDG PET/CT for health screening were also enrolled to compare the incidence of PILs with HCC patients. Various parameters associated with patient demographics and characteristics of HCC were analyzed to find the related factors of PILs. RESULTS: A total of 17,674 patients with HCC and 2,090 healthy individuals who had undergone 18F-FDG PET/CT scans were enrolled in the analyses. Among the 54 HCC patients who underwent pathological confirmation for PILs, benign primary parotid tumor was most commonly observed (n = 43 [79.6%]); however, no malignant lesions were detected, including HCC metastasis. The incidence of PILs was higher in patients diagnosed with HCC compared with the control group (485 [2.7%] vs. 23 [1.1%], p = 0.002). Analysis for the risk factors for PILs revealed that patient age, sex, and positive viral markers were significantly associated with the incidence of PILs in patients with HCC (all p < 0.001). CONCLUSIONS: Our study demonstrates that PILs are more frequently identified in patients with HCC on 18F-FDG PET/CT. However, no malignant PIL, including extrahepatic metastasis of HCC, was identified. Therefore, the presence of PIL should not impede or delay the treatment process for patients with HCC. Additionally, we suggested that for future swift and straightforward differential diagnoses of PIL, the development of additional protocols within the PET/CT imaging could be beneficial.

MRI-based radiomics for predicting histology in malignant salivary gland tumors: methodology and "proof of principle".

Defining the exact histological features of salivary gland malignancies before treatment remains an unsolved problem that compromises the ability to tailor further therapeutic steps individually. Radiomics, a new methodology to extract quantitative information from medical images, could contribute to characterizing the individual cancer phenotype already before treatment in a fast and non-invasive way. Consequently, the standardization and implementation of radiomic analysis in the clinical routine work to predict histology of salivary gland cancer (SGC) could also provide improvements in clinical decision-making. In this study, we aimed to investigate the potential of radiomic features as imaging biomarker to distinguish between high grade and low-grade salivary gland malignancies. We have also investigated the effect of image and feature level harmonization on the performance of radiomic models. For this study, our dual center cohort consisted of 126 patients, with histologically proven SGC, who underwent curative-intent treatment in two tertiary oncology centers. We extracted and analyzed the radiomics features of 120 pre-therapeutic MRI images with gadolinium (T1 sequences), and correlated those with the definitive post-operative histology. In our study the best radiomic model achieved average AUC of 0.66 and balanced accuracy of 0.63. According to the results, there is significant difference between the performance of models based on MRI intensity normalized images + harmonized features and other models (p value < 0.05) which indicates that in case of dealing with heterogeneous dataset, applying the harmonization methods is beneficial. Among radiomic features minimum intensity from first order, and gray level-variance from texture category were frequently selected during multivariate analysis which indicate the potential of these features as being used as imaging biomarker. The present bicentric study presents for the first time the feasibility of implementing MR-based, handcrafted radiomics, based on T1 contrast-enhanced sequences and the ComBat harmonization method in an effort to predict the formal grading of salivary gland carcinoma with satisfactory performance.

Imaging of salivary gland cancers derived from a sublingual gland herniated into the submandibular space: a report of three cases.

Sublingual gland herniation into the submandibular space through a mylohyoid muscle defect is a common anatomical variation; however, salivary gland cancers that arise from a herniated sublingual gland have not been described yet. Here, we report three patients with salivary gland cancers originating from a herniated sublingual gland. All tumors were detected as palpable submandibular masses, located anterior to the submandibular gland, medial to the mandible, and lateral to the mylohyoid muscle, with contact with the sublingual gland through a mylohyoid muscle defect. Intraoperative findings confirmed that the masses were derived from herniated sublingual glands. Pathological examination showed one case of mucoepidermoid carcinoma and two cases of adenoid cystic carcinoma. Imaging findings of the tumor location, in addition to the continuity with the sublingual gland through the mylohyoid muscle defect, are crucial for accurately diagnosing the tumor origin, which is essential for determining the appropriate clinical management.

Differentiation of salivary gland tumours using diffusion-weighted image-based virtual MR elastography: a pilot study.

OBJECTIVES: Differentiation among benign salivary gland tumours, Warthin tumours (WTs), and malignant salivary gland tumours is crucial to treatment planning and predicting patient prognosis. However, differentiation of those tumours using imaging findings remains difficult. This study evaluated the usefulness of elasticity determined from diffusion-weighted image (DWI)-based virtual MR elastography (MRE) compared with conventional magnetic resonance imaging (MRI) findings in differentiating the tumours. METHODS: This study included 17 benign salivary gland tumours, 6 WTs, and 11 malignant salivary gland tumours scanned on neck MRI. The long and short diameters, T1 and T2 signal intensities, tumour margins, apparent diffusion coefficient (ADC) values, and elasticity from DWI-based virtual MRE of the tumours were evaluated. The interobserver agreement in measuring tumour elasticity and the receiver operating characteristic (ROC) curves were also assessed. RESULTS: The long and short diameters and the T1 and T2 signal intensities showed no significant difference among the 3 tumour groups. Tumour margins and the mean ADC values showed significant differences among some tumour groups. The elasticity from virtual MRE showed significant differences among all 3 tumour groups and the interobserver agreement was excellent. The area under the ROC curves of the elasticity were higher than those of tumour margins and mean ADC values. CONCLUSION: Elasticity values based on DWI-based virtual MRE of benign salivary gland tumours, WTs, and malignant salivary gland tumours were significantly different. The elasticity of WTs was the highest and that of benign tumours was the lowest. The elasticity from DWI-based virtual MRE may aid in the differential diagnosis of salivary gland tumours.

An ultrasound-based histogram analysis model for prediction of tumour stroma ratio in pleomorphic adenoma of the salivary gland.

OBJECTIVES: Preoperative identification of different stromal subtypes of pleomorphic adenoma (PA) of the salivary gland is crucial for making treatment decisions. We aimed to develop and validate a model based on histogram analysis (HA) of ultrasound (US) images for predicting tumour stroma ratio (TSR) in salivary gland PA. METHODS: A total of 219 PA patients were divided into low-TSR (stroma-low) and high-TSR (stroma-high) groups and enrolled in a training cohort (n = 151) and a validation cohort (n = 68). The least absolute shrinkage and selection operator regression algorithm was used to screen the most optimal clinical, US, and HA features. The selected features were entered into multivariable logistic regression analyses for further selection of independent predictors. Different models, including the nomogram model, the clinic-US (Clin + US) model, and the HA model, were built based on independent predictors using logistic regression. The performance levels of the models were evaluated and validated on the training and validation cohorts. RESULTS: Lesion size, shape, cystic areas, vascularity, HA_mean, and HA_skewness were identified as independent predictors for constructing the nomogram model. The nomogram model incorporating the clinical, US, and HA features achieved areas under the curve of 0.839 and 0.852 in the training and validation cohorts, respectively, demonstrating good predictive performance and calibration. Decision curve analysis and clinical impact curves further confirmed its clinical usefulness. CONCLUSIONS: The nomogram model we developed offers a practical tool for preoperative TSR prediction in PA, potentially enhancing clinical decision-making.

Salivary gland secretory carcinoma presenting as a cervical soft tissue mass: a case report.

BACKGROUND: Secretory carcinoma (SC) has been described as a distinct salivary gland tumor in the fourth edition of the World Health Organization (WHO) classification of head and neck tumors. SC is generally considered as a slow-growing low-grade malignant tumor, while several cases have been reported with high-grade features, and even metastases in the literature up until now. In this article, a soft tissue SC case is discussed with high-grade microscopic features and neural invasion. A review of the salivary gland SC cases with aggressive behavior is also debated. CASE PRESENTATION: A 65-year-old Caucasian man presented with a left neck mass for the past six months. The imaging studies demonstrated a very large cystic cervical mass (46 × 23 mm) with papillary projections in the anterolateral aspect of the left neck zone Vb. He underwent left radical neck dissection (level I-V) and was followed up for 12 months with the diagnosis of Secretory carcinoma. CONCLUSION: Although SC generally has a good outcome, multiple recurrences and unusual metastases may occur, which should be considered by either the pathologists or clinicians.

Diagnostic imaging of salivary gland cancers: REFCOR recommendations by the formal consensus method.

OBJECTIVE: To define the indications for each imaging modality in the screening, characterization, extension and follow-up of salivary gland tumors. MATERIAL AND METHODS: The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method. RESULTS: If a swelling of a salivary gland is palpable for 3 weeks, an ultrasound scan is recommended to confirm a tumoral lesion and rule out differential diagnoses. For a salivary gland tumor, MRI is recommended with diffusion-weighted and dynamic contrast-enhanced techniques. In the case of histologically proven malignancy or a highly suspicious lesion, a CT scan of the neck and chest is recommended to assess the tumor, lymph nodes and metastases. FDG-PET is not currently recommended in routine clinical practice for initial diagnosis, assessment of extension, evaluation of response to treatment, staging of recurrence, or follow-up of salivary gland tumors. CONCLUSION: Assessing salivary tumors is based on MRI. Extension assessment is based on neck and chest CT.

Submandibular gland carcinoma ex pleomorphic adenoma with calcification.

We report an unusual case of carcinoma ex pleomorphic adenoma (CXPA) in the submandibular gland. The mass had a unique calcification. Panoramic tomography revealed sponge-like calcification. The central portion displayed heterogeneous high signal intensity on T1-weighted image (T1WI) and T2-weighted image (T2WI), and heterogeneously moderate signal intensity on a short-TI inversion recovery (STIR) image. The ADC was low (0.78 × 10-3mm2/sec). After surgical excision, a pathological examination revealed that the mass contained CXPA as a minor component. Tumor cells with large hyperchromatic nuclei and eosinophilic or clear cytoplasm proliferated in irregular small tubule formations or cribriform or Roman-bridge structures in hyalinized or focally ossified stroma. The entire mass was calcified, particularly in the central region. Taken together, the reduced T1 relaxation times were related to the surface effects of diamagnetic particles, which were observed at calcium particle concentrations of up to 30%. We report a CXPA with unusual sponge-like calcification, which appeared unusually hyperintense on T1WI due to a surface effect.

Use of Computed Tomography-Based Texture Analysis to Differentiate Benign From Malignant Salivary Gland Lesions.

OBJECTIVE: Salivary gland lesions show overlapping morphological findings and types of time/intensity curves. This research aimed to evaluate the role of 2-phase multislice spiral computed tomography (MSCT) texture analysis in differentiating between benign and malignant salivary gland lesions. METHODS: In this prospective study, MSCT was carried out on 90 patients. Each lesion was segmented on axial computed tomography (CT) images manually, and 33 texture features and morphological CT features were assessed. Logistic regression analysis was used to confirm predictors of malignancy ( P < 0.05 was considered to be statistically significant), followed by receiver operating characteristics analysis to assess the diagnostic performance. RESULTS: Univariate logistic regression analysis revealed that morphological CT features (shape, size, and invasion of adjacent tissues) and 17 CT texture parameters had significant differences between benign and malignant lesions ( P < 0.05). Multivariate binary logistic regression demonstrated that shape, invasion of adjacent tissues, entropy, and inverse difference moment were independent factors for malignant tumors. The diagnostic accuracy values of multivariate binary logistic models based on morphological parameters, CT texture features, and a combination of both were 87.8%, 90%, and 93.3%, respectively. CONCLUSIONS: Two-phase MSCT texture analysis was conducive to differentiating between malignant and benign neoplasms in the salivary gland, especially when combined with morphological CT features.

INFLUENCE OF THE PATIENT'S SEX AND AGE, VOLUMES OF THE SALIVARY GLAND AND PLEOMORPHIC ADENOMA ON THE TUMOR HISTOLOGICAL VARIANTS.

OBJECTIVE: Aim: The purpose of the study was to identify the influence of the patient's sex and age, the volumes of the salivary gland and pleomorphic adenoma on the histological variants of the tumor. PATIENTS AND METHODS: Materials and Methods: The study included 21 women and 9 men with pleomorphic adenomas of the salivary gland. In 15 cases, a mesenchymal variant of pleomorphic adenoma was identified, in 5 cases - an epithelial variant, in 10 cases - a mixed variant. The average age of the patients was 39.7±2.9 years. Patients with pleomorphic adenomas underwent magnetic resonance imaging using a Siemens MAGNETOM Aera 1.5T device (Germany), during which three projections of the tumor and salivary gland were measured (antero-posterior, lateral, vertical) with subsequent calculation of their volumes, and then the ratios of these volumes. Classification trees were used to determine whether patients belonged to one of three variants of pleomorphic adenoma. The CART (Classification And Regression Tree) algorithm was used as a branching option. Stopping branching was carried out using the FACT (Fact-style direct stopping) method until each terminal (final) node of the tree does not contain incorrectly classified observations or when their number becomes less than a given proportion of the total group size (less than 5%). Determination of the structure and relationships between the tumor variants and such indicators as gender, age and radiological indicators (volume of the tumor, volume of the salivary gland, ratio of tumor volume to salivary gland volume) was carried out using correspondence analysis. RESULTS: Results: Epithelial variant of pleomorphic adenoma is more typical for women, and the mixed and mesenchymal variant is more common for patients of both sexes. The epithelial variant can develop in patients of any age, while the mixed variant occurs mainly in patients older than 41 years, and the mesenchymal variant - mainly in patients younger than 41 years. The ratio of the volume of the tumor to the volume of the salivary gland will be predominantly >0.17 in the epithelial variant of pleomorphic adenoma, predominantly ≤0.17 in the mesenchymal variant, and can take any value in the mixed variant. CONCLUSION: Conclusions: The authors conducted a study in order to identify the influence of sex, age of the patient, and the ratio of the volume of pleomorphic adenoma to the volume of the salivary gland on the histological variant of the tumor. The revealed data will be useful in the treatment and diagnostic process in patients with pleomorphic adenoma of the salivary gland.

[Imaging findings of carcinoma ex pleomorphic adenoma in minor salivary glands].

PURPOSE: To summarize the CT and MR imaging features of carcinoma ex pleomorphic adenoma(Ca-ex-PA) in minor salivary gland, and analyze the correlation between various features and pathological classification. METHODS: Forty-three patients with Ca-ex-PA in minor salivary gland were collected. The CT and MRI findings were retrospectively analyzed and correlated with their pathological types. Fisher's exact test was used to analyze the correlation between various imaging features (tumor morphology, boundary, internal structure, bone invasion, cervical lymph node metastasis) and pathological types with SPSS 25.0 software package. RESULTS: Among the 43 patients with Ca-ex-PA, 83.7%(36/43) of the tumors were lobulated; 81.4%(35/43) showed cystic degeneration or necrosis, with heterogeneous enhancement. Coarse calcification or mixed calcification was found in 37.2%(16/43), 25.6%(11/43) had compressive absorption of adjacent bone. 75%(12/16) of type Ⅰ/Ⅱ tumors had regular morphology (round or oval), and 77.8%(21/27) of type Ⅲ tumors had irregular morphology, 93.8%(15/16) of type Ⅰ/Ⅱ tumors had well-defined margin and 66.7%(18/27) of type Ⅲ tumors had ill-defined margin. Osteolytic bone resorption occurred in 59.3%(16/27) of type Ⅲ tumors. The average maximum diameter of type Ⅰ/Ⅱ tumors was significantly shorter than that of type Ⅲ(P＜0.05). Fisher's exact test showed the characteristics of tumor morphology, boundary and osteolytic bone resorption were related to pathological grouping(P＜0.001). CONCLUSIONS: Most Ca-ex-PA in minor salivary glands is characterized by lobular and heterogeneous enhanced neoplasm on CT and MR imaging. A round or oval tumor with well-defined margin usually correlates with typeⅠ and Ⅱ, contrarily, an irregular mass with ill-defined margin and osteolytic bone destruction usually correlates with type Ⅲ. Combining the three characteristics of morphology, boundary and osteolysis is more helpful to distinguish type Ⅰ/Ⅱ and type Ⅲ tumors.

Neural network combining with clinical ultrasonography: A new approach for classification of salivary gland tumors.

OBJECTIVE: Little information is available about deep learning methods used in ultrasound images of salivary gland tumors. We aimed to compare the accuracy of the ultrasound-trained model to computed tomography or magnetic resonance imaging trained model. MATERIALS AND METHODS: Six hundred and thirty-eight patients were included in this retrospective study. There were 558 benign and 80 malignant salivary gland tumors. A total of 500 images (250 benign and 250 malignant) were acquired in the training and validation set, then 62 images (31 benign and 31 malignant) in the test set. Both machine learning and deep learning were used in our model. RESULTS: The test accuracy, sensitivity, and specificity of our final model were 93.5%, 100%, and 87%, respectively. There were no over fitting in our model as the validation accuracy was similar with the test accuracy. CONCLUSIONS: The sensitivity and specificity were comparable with current MRI and CT images using artificial intelligence.

Intraductal Carcinoma: The Carcinoma In Situ of the Salivary Gland.

Intraductal carcinoma of the salivary gland (IDC) is a rare in situ neoplasm of the salivary gland with similar features to the ductal carcinoma in situ of the breast. This report aims to present the clinical presentation and histological features of IDC. The authors present a 90-year-old gentleman with an indurated and painless tumor within the right parotid. Preoperative diagnostics, including fine needle aspiration cytology, ultrasound scan, and magnetic resonance imaging, were suggestive of Warthin tumor. The tumour was excised by extracapsular dissection. The patient is disease free within the follow-up period of 33 months. Intraductal carcinoma is an indolent phenotype with only a few reported cases with nodal metastases, and to the best of our knowledge, no cases have been reported with distant metastases. Complete surgical excision is recommended to prevent a recurrence. The knowledge of this underreported salivary gland malignancy is important to prevent misdiagnosis and insufficient treatment.

Efficacy of Ultrasound Shear Wave Elastography in the Diagnosis of Salivary Gland Tumors.

PURPOSE: Diagnostic accuracy of fine-needle aspiration cytology (FNAC) to discriminate between the target condition and health in the evaluation of salivary gland tumors is not perfected yet and thus, false-negative results are possible. The purpose of the present study was to measure and compare the diagnostic accuracy of FNAC performed with conventional B-mode ultrasound and ultrasound with shear wave elastography (SWE) FNAC navigation. METHODS: The investigators implemented a single-blind randomized study (sealed envelope method). The study population was composed of all patients presenting for evaluation and management of suspected benign or malignant tumors of the major salivary glands between July 2013 and December 2020. The involvement of SWE navigation was the primary predictor variable affecting FNA targeting. The method involved analysis of redistribution of SWE values within the affected gland expressed in kilopascals (kPa) and the four-point ES1 (soft tissue) to ES4 (stiff) scoring. The primary outcome variable was the success in obtaining diagnostic tissue resulting in a histologically confirmed FNAC diagnosis and coded as yes/no. Age and sex of the patients and topographical locations of lesions were covariates. Descriptive and bivariate statistics were computed and the P value was set at .05. RESULTS: The sample included 132 subjects (male/female 59/73; mean age 54 ± 11 years; 144 tumors). SWE + Group (n = 66) consisted of patients presurgically diagnosed with salivary tumors SWE-guided FNAC and SWE- Group (n = 66) was diagnosed with tumors by conventional ultrasound-(B-mode)-guided FNAC. The SWE-guided FNAC statistically significantly reduced the incidence of false-negative results (n = 0; P = .001) and nondiagnostic cases (n = 3 SWE FNAC vs n = 7 B-mode US FNAC; P = .04). For SWE + Group, the FNAC diagnosis was confirmed by postsurgical histology in 95.5% with 91.0% sensitivity (confidence interval [CI] 0.62 to 0.97) and 84.4% specificity (CI 0.58 to 0.96). For SWE- Group, 81.8% confirmation was obtained (P = .05) with 82.3% sensitivity (CI 0.54 to 0.90) and 74.0% specificity. CONCLUSION: SWE can increase success in obtaining diagnostic tissue when used for FNAC navigation purposes. We suggest combining both SWE and standard B-mode ultrasonography methods when the FNAC procedure is performed.

Pleomorphic Adenoma of the Palate: A Rare Case in an Adolescent With Cleft lip and Palate.

Benign salivary gland tumors are rarely found in children and adolescents compared with adults. Pleomorphic adenomas (PAs), the most common benign salivary gland tumor, account for only 1% of all head and neck lesions and fewer than 5% of all salivary gland tumors in individuals under the age of 16 years. The data on palatal PA in the first 2 decades of life is confined to published case reports and case series. To date, there has never been a report of palatal PA in a patient with cleft lip and palate. Here we describe an adolescent female with bilateral cleft lip and palate with PA of the hard and soft palate who underwent wide local excision and reconstruction with a buccal fat pad and buccal myo-mucosal flap.

Polar Vessel: A New Ultrasound Sign for Complementary Diagnosis of Major Salivary Gland Adenoid Cystic Carcinoma.

OBJECTIVES: To investigate the characteristic ultrasonographic findings of adenoid cystic carcinoma (ACC) in major salivary glands and identify the value of polar vessel in color Doppler flow imaging (CDFI) for the diagnosis of ACC. METHODS: From January 2017 to December 2021, 76 patients with parotid and submandibular gland tumors, including 14 patients with ACC, as confirmed by surgery and histopathology, were enrolled. Their clinicopathologic information and ultrasound (US) features were recorded and analyzed. The performance of polar vessel in CDFI for differentiating ACC from non-ACC (benign tumors and mucoepidermoid carcinoma [MEC]) was analyzed. RESULTS: ACC in the major salivary gland was more likely to be associated with pain symptoms (P = .027) and unclear borders and rough edges in grayscale US (P = .002, .015, respectively) than benign tumors. Compared to MEC, ACC tended to feature a homogeneous internal echo (P = .008). ACC of the major salivary gland had a significantly higher incidence of polar vessel sign than that of non-ACC (benign tumors and MEC) (P < .0001, .0001, respectively). The polar vessel sign showed good performance in distinguishing between ACC and non-ACC, with an area under the receiver operating characteristic curve of 0.857, a sensitivity of 71.4%, a specificity of 100%, and an accuracy of 94.7%. Positive predictive value and negative predictive value were calculated at 100% and 93.9%, respectively. CONCLUSIONS: The US sign of polar vessel has high diagnostic efficiency, and it may have important potential for use as a new complementary sign for the diagnosis of ACC in major salivary glands.

Potential role of hybrid positron emission tomography in pre-operative assessment of primary salivary gland carcinomas.

OBJECTIVE: The added value of hybrid positron emission tomography is increasingly recognised in head and neck cancer. However, its potential role in salivary gland carcinomas has been scarcely investigated. METHODS: A consecutive cohort of 45 salivary gland carcinoma patients who underwent pre-therapeutic hybrid positron emission tomography and surgical resection was reviewed. This study investigated whether maximum standardised uptake value correlated with tumour phenotype. RESULTS: Tumours of high-grade disease on histology (salivary duct carcinoma, carcinoma ex pleomorphic adenoma) had higher maximum standardised uptake value (Kruskal-Wallis test, p = 0.011) than low-grade tumours (adenoid cystic carcinoma and acinic cell carcinoma). Patients with pathologically confirmed node-positive disease had significantly higher maximum standardised uptake value of the primary tumour than patients with pathologically confirmed node-negative disease (Kruskal-Wallis test, p = 0.012). CONCLUSION: Maximum standardised uptake value of the primary tumour may guide clinical decision-making in patients with salivary gland carcinomas, as a high maximum standardised uptake value is associated with high-grade tumour histology and the presence of lymph node metastases. Clinicians may consider more aggressive surgery for these patients.

Discriminating between benign and malignant salivary gland tumors using diffusion-weighted imaging and intravoxel incoherent motion at 3 Tesla.

PURPOSE: The purpose of this study was to retrospectively evaluate the diagnostic performances of diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) for discriminating between benign and malignant salivary gland tumors (SGTs). MATERIALS AND METHODS: Sixty-seven patients with 71 SGTs who underwent MRI examination at 3 Tesla were included. There were 34 men and 37 women with a mean age of 57 ± 17 (SD) years (age range: 20-90 years). SGTs included 21 malignant tumors (MTs) and 50 benign SGTs (33 pleomorphic adenomas [PAs] and 17 Warthin's tumors [WTs]). For each SGT, DWI and IVIM parameters, mean, skewness, and kurtosis of apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion volume fraction (f) were calculated and further compared between SGTs using univariable analysis. Areas under the curves (AUC) of receiver operating characteristic of significant parameters were compared using the Delong test. RESULTS: Significant differences in ADCmean, Dmean and D*mean were found between SGTs (P < 0.001). The highest AUC values were obtained for ADCmean (0.949) for identifying PAs and D*mean (0.985) for identifying WTs and skewness and kurtosis did not outperform mean. To discriminate benign from malignant SGTs with thresholds set to maximize Youden index, IVIM and DWI produced accuracies of 85.9% (61/71; 95% CI: 75.6-93.0) and 77.5% (55/71; 95% CI: 66.0-86.5) but misdiagnosed MTs as benign in 28.6% (6/21) and 61.9% (13/21) of SGTs, respectively. After maximizing specificity to 100% for benign SGTs, the accuracies of IVIM and DWI decreased to 76.1% (54/71; 95% CI: 64.5-85.4) and 64.8% (46/71; 95% CI: 52.5-75.8) but no MTs were misdiagnosed as benign. IVIM and DWI correctly diagnosed 66.0% (33/50) and 50.0% (25/50) of benign SGTs and 46.5% (33/71) and 35.2% (25/71) of all SGTs, respectively. CONCLUSION: IVIM is more accurate than DWI for discriminating between benign and malignant SGTs because of its advantage in detecting WTs. Thresholds set by maximizing specificity for benign SGTs may be advantageous in a clinical setting.

Clinical, laboratory, pathological, and radiological characteristics and prognosis of patients with pulmonary salivary gland-type tumors.

PURPOSE: Primary pulmonary salivary gland-type tumor (PSGT) included two main subtypes, pulmonary adenoid cystic carcinoma (PACC) and pulmonary mucoepidermoid carcinoma (PMEC). The purpose of this study was to compare the similarities and differences between these two subtypes and to identify independent risk factors for the prognosis of PSGT patients. METHODS: This study screened patients with a pathological diagnosis of PSGT in Beijing Chaoyang Hospital between 2010 and 2021. The clinical, pathological, radiological, laboratory test, and other characteristics were collected, and t, nonparametric and chi-squared tests were used to compare the differences in clinical characteristics of the two subtypes. COX univariate and multivariate analyses were used to explore prognostic-related risk factors. RESULTS: A total of 62 patients with PSGT were included in our center over a 12-year period. There were 26 PMEC patients and 36 PACC patients. There were differences in the clinical, pathological, and radiological features of the two tumor subtypes. Univariate analysis showed that weight loss, chemotherapy, white blood cells, lymphocytes, red blood cells, total protein, and total bilirubin might be related to the prognosis in PSGT patients. Multivariate results showed that lymphocytes (p = 0.031), red blood cells (p = 0.047), total protein (p = 0.032), and total bilirubin (p = 0.010) were independent prognostic risk factors. Chemotherapy (HR 4.452; 95% CI 1.723-11.503; p = 0.002) might be associated with progression-free survival (PFS). CONCLUSION: The two subtypes of PSGT had significantly different clinical, laboratory, pathological, and radiological features. However, there was no significant difference in the prognosis of patients with PMEC and PACC subtypes. Cox univariate and multivariate analyses showed that levels of lymphocytes, erythrocytes, total protein and total bilirubin in the peripheral blood of PSGT patients might be related to patient overall survival. Chemotherapy might also be associated with PFS.