Warthin's Tumor Research Articles

Imaging quality of PROPELLER diffusion-weighted MR imaging and its diagnostic performance in distinguishing pleomorphic adenomas from Warthin tumors of the parotid gland.

The aim of this study was to evaluate the imaging quality and diagnostic performance of fast spin echo diffusion-weighted imaging with periodically rotated overlapping parallel lines with enhanced reconstruction (FSE-PROP-DWI) in distinguishing parotid pleomorphic adenoma (PMA) from Warthin tumor (WT). This retrospective study enrolled 44 parotid gland tumors from 34 patients, including 15 PMAs and 29 WTs with waived written informed consent. All participants underwent 1.5 T diffusion-weighted imaging including FSE-PROP-DWI and single-shot echo-planar diffusion-weighted imaging (SS-EP-DWI). After imaging resizing and registration among T2WI, FSE-PROP-DWI and SS-EP-DWI, imaging distortion was quantitatively analyzed by using the Dice coefficient. Signal-to-noise ratio and contrast-to-noise ratio were qualitatively evaluated. The mean apparent diffusion coefficient (ADC) of parotid gland tumors was calculated. Wilcoxon signed-rank test was used for paired comparison between FSE-PROP-DWI versus SS-EP-DWI. Mann-Whitney U test was used for independent group comparison between PMAs versus WTs. Diagnostic performance was evaluated by receiver operating characteristics curve analysis. P < 0.05 was considered statistically significant. The Dice coefficient was statistically significantly higher on FSE-PROP-DWI than SS-EP-DWI for both tumors (P < 0.005). Mean ADC was statistically significantly higher in PMAs than WTs on both FSE-PROP-DWI and SS-EP-DWI (P < 0.005). FSE-PROP-DWI and SS-EP-DWI successfully distinguished PMAs from WTs with an AUC of 0.880 and 0.945, respectively (P < 0.05). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy in diagnosing PMAs were 100%, 69.0%, 62.5%, 100% and 79.5% for FSE-PROP-DWI, and 100%, 82.8%, 75%, 100% and 88.6% for SS-EP-DWI, respectively. FSE-PROP-DWI is useful to distinguish parotid PMAs from WTs with less distortion of tumors but lower AUC than SS-EP-DWI.

Clinical and own experience in the treatment of major salivary gland tumors

The paper aims to demonstrate the Clinic's and own research in the treatment of major salivary gland tumors. In the years 2013-2019, there were 95 salivary gland surgeries, including 45 performed in women (47.36%) aged between 24 and 82 and in 50 men (52.64%) aged 29 to 86. Diagnostics of major salivary glands included: patient history, otolaryngological examination, ultrasound and fine needle aspiration (BACC) (of tumor), laboratory tests (morphology, CRP) and computed tomography (CT) or magnetic resonance imaging (MRI) to accurately assess salivary glands, location of lesion and lymph nodes prior to elective surgery. Research results: In the analyzed material patients with major salivary gland tumors were most frequently operated on at the age of 61-70 (34.7%) and 51-60 years (23.2%). Most patients with tumors were hospitalized in the last 4 years between 2016-2019, which accounted for 77.8% of all operated cases. Among the operated lesions, benign neoplasms and tumors occurred in 93.7%, of which the most frequent findings in histopathological examination were Warthin tumor in 50.5%, and multiform adenoma in 26.3%. The remaining tumors and benign neoplasms constituted only 16.9% and were observed in isolated cases, including eosinophilic adenoma, lymphoepithelial cyst, myoepithelial adenoma, lipofibrosarcoma, congestive cyst, air cyst, tubular adenoma, basal cell carcinoma, cyst with squamous metaplasia features, vascular malformation. Malignant salivary gland tumors were found in 6.3%, including the following malignant tumors were revealed histopathologically: adenocarcinoma, mucoepidermal carcinoma, acinocellular carcinoma, epithelialmyoepithelial carcinoma, ductal carcinoma. The majority of operated salivary gland tumors were benign (93.7%), of which the most common histopathologically were: Warthin tumor (50.5%) and multiform adenoma (26.3%), while malignant tumors occurred in 6.3%. Tumors were localized mainly in the parotid gland in as many as 93.7% cases, of which the most common localization concerned the superficial lobe in 56.8%. The most frequent surgical technique used in the Clinic was extracapsular dissection of the tumor in 88.4%, and other methods were used rarely.

A novel case of a benign parotid adenoma with divergent features

Introduction: The parotid gland is the most frequent site of salivary gland tumours, most of these are benign. Case: We present a novel case of an 86-year-old gentleman with a benign adenoma showing divergent features. He presented with a painless swelling in his left parotid gland, which showed scant oncocytic cells on fine needle aspiration. Parotidectomy was then undertaken for definitive diagnosis and treatment. The surgical specimen showed a 43 mm well circumscribed, heterogeneous tumour expanding the parotid gland. There were solid tan areas intermixed with friable yellow nodules in a background of adipose tissue. Microscopic assessment showed sheets, small nests and single oncocytic cells scattered throughout a background of mature adipose tissue. There were expanses of lymphoepithelial tissue with squamous metaplasia and variable cystic change alongside sebaceous metaplasia, and Warthin's tumour-like areas. Mitotic activity, necrosis and malignancy were not seen. Conclusion: Our case is unique as it describes a benign adenoma demonstrating multiple histological tumours sub-types including sebaceous lymphadenoma, Warthin's tumour, oncocytoma, sialolipoma / lipoadenoma. Similar cases, with such wide morphology, have not previously been described in the literature. Although exact prognosis is not known, it is thought likely to behave in a benign fashion.

Warthin's tumor mimicking metastasis from lung cancer.

Warthin's tumor mimicking metastasis from lung cancer.

Cytomorphological findings in diagnosis of Warthin tumor

Background/aim To define the cytomorphologic findings leading to difficulties in diagnosis of Warthin tumors (WTs).Materials and methodsForty-eight histopathologically diagnosed WT patients who had fine needle aspiration cytology preoperatively were reevaluated for defining the presence or absence of lymphocytes, oncocytic cell layer, oncocytic cell papillae, granular debris background, mucoid background, macrophages, polymorphonuclear cells, mast cells, squamous-like cells, atypical vacuolated cytoplasmic cells, and giant cells.ResultsForty-seven tumors were in the parotid gland and one in the submandibular gland. There were 37 (77%) male and 11 (23%) female patients. Cytopathologically in 36 patients the diagnosis was benign neoplasm (WT); in 6, other benign entities; and in 6, suspicious for malignancy. The main characteristic cytomorphologic features of WTs were as follows: 92% lymphoid cells, 83% oncocytic cell layers, and 67% granular debris background. These percentages were 67%, 17%, and 17% in the benign cytology group and 67%, 50%, and 17% in the suspicious for malignancy group, respectively.ConclusionAbsence or lack of main features of WTs with or without presence of squamous-like cells, vacuolated cytoplasmic cells, and inflammatory reaction may cause diagnostic dilemma. The presence of the mast cells accompanied by epithelial tissue was striking for WT diagnosis.

Salivary gland tumors: A 15-year experience of a university hospital in Turkey.

OBJECTIVE:To determine the demographic characteristics of benign and malignant salivary gland tumors in our department in the last 15 years.METHODS:In this study, the files of the patients who underwent salivary gland surgery between 2004 and 2019 in our department were analyzed retrospectively. A total of 366 patients whose diagnoses of salivary gland tumor histopathologically confirmed were included in this study. The demographic data of the patients and tumor localizations were recorded, and their relationships with histopathological results were examined.RESULTS:Of the 366 tumors, 292 (80%) of them was originated from the parotid gland, 52 (14%) from the submandibular gland, and 22 (6%) from the minor salivary gland. The male: female ratio was found as 1.2:1, and the mean age of the patients was 50.37 years. A total of 259 (70.8%) tumors were benign, and 107 (29.2%) were malignant. The most frequent benign tumor was pleomorphic adenoma, with 121 cases (46.7%). While pleomorphic adenomas constituted the majority of the benign tumors of the submandibular gland and minor salivary glands, Warthin tumor was detected more than pleomorphic adenoma in the parotid gland. The most common malignant tumor was mucoepidermoid carcinoma, with 26 cases (24.3%).CONCLUSION:The distribution of the salivary gland tumors detected in our department was found to be substantially similar to other worldwide series. Unlike the literature, we concluded that salivary gland tumors were seen slightly more in males, minor salivary gland tumors were relatively rare and Warthin tumors were more frequently detected in our region.

Parotid gland neoplasms presenting as discrete infra-auricular swellings

Background: Parotid gland neoplasms usually present as pre-auricular swellings. Sometimes, they present as solitary infra-auricular swellings which make their localization difficult as they may be confused with submandibular gland or other lateral upper neck masses. Clinicopathological reports of discrete infra-auricular parotid lesions and their surgical managements are few. Objectives: To describe the clinical features and management of discrete infra-auricular parotid masses in a series of Nigerian patients seen during a surgical outreach mission. Methodology: This is a retrospective study of all infra-auricular swellings managed by a Nigerian surgical mission over 6 years. Patients' demographics, duration of swelling, symptoms, treatment, histopathological diagnosis, postoperative complications were retrieved from patients' records. Results: A total of 124 facial tumors were seen, of which 15 (12.1%) were parotid tumors. Eight cases (53.3%) of parotid tumors presented as discrete infra-auricular masses. Age range was 13–57 years (mean = 40.9 ± 15.4 years) with male predilection. Duration of swelling was between 1 and 15 years. All lesions were treated with extracapsular dissection. One patient had postoperative facial nerve paresis, but no facial palsy and sialocele. The histopathological results were 5 (62.5%) pleomorphic adenomas, 1 (12.5%) Warthin's tumor, and 2 (25%) low-grade mucoepidermoid carcinomas. Conclusion: Discrete infra-auricular swellings may present as benign and malignant parotid gland neoplasms.

Clinical profile of patients with salivary gland tumours

In sublingual glands 85% are malignant and only 15% are benign. The incidence of malignancy in submandibular gland is higher than parotid gland and the prognosis is poorer than parotid malignancies. Risk factors linked to the development of salivary gland neoplasia include: radiation exposure; familial or genetic predisposition; tobacco use: strong association between tobacco use and the development of Warthin's tumor; microorganisms: Epstein Barr virus linked lymphoepithelial carcinoma; exposure to industrial chemicals. Total 20 cases clinically presenting as salivary gland tumours during the study period were taken for study. Each case was examined clinically and properly in a systematic manner. The cases were treated on their individual merits. All patients presented with swelling. Features of rapid growth, pain, and associated facial paralysis were considered as signs of malignancy. One out of 20 patients presented with pain in swelling, that was malignant. Features of fixity, facial paralysis and nodal involvement were considered as signs of malignancy. Hard in consistency suggests malignancy. All patients in this study had only swelling and no other signs.

Treatment approaches for benign tumors of major salivary glands

Introduction: Salivary gland tumours (SGT) are heterogenous group of neoplasms in the maxillofacial area with complex morphologic appearances and different clinical behaviour. They often present as painless enlarging masses, mostly located in parotid glands and mostly benign. Epidemiology: SGT’s are more common in women than in men which represents 2%-3% of head and neck neoplasms. Pleomorphic adenomas are most common benign SGT’s followed by Warthin tumours. Treatment: Difficulty with salivary gland tumour is they are rare and have long clinical course that requires follow up data for a decade or more. Prospective randomised trails have therefore not been undertaken and hence progress happens slowly. Improved methods of assessment (MRI, CT, Ultrasound, fine needle aspiration biopsy) have had major impact on salivary gland surgery. Most benign tumours are either pleomorphic adenomas (71%) or Warthin’s tumours (22%). Conclusion: Treatment for this include both medical and surgical therapy. Medical therapy is indicated for inflammatory infectious masses (eg: reactive or fungal) and lymphoma. When symptomatic, recurrent chronic gland infection (eg: parotitis) proves refractory to conservative medical or endoscopic (i.e. sialoendoscopy) treatments, salivary gland excision is sometimes indicated. Surgical therapy includes parotidectomy and submandibular gland surgery.

Divergent prevalence of Warthin tumor in Africa and Asia: A consequence of variation in smoking index?

Aim: This study assessed the prevalence of WT in Africa and Asia as it relates to smoking index and malignant tumors of the parotid gland. Materials and Methods: Peer-reviewed articles found on Google Scholar, Scopus, EMBASE, Web of Science, and PubMed Central were systematically reviewed. Results: Significant higher prevalence of WT and smoking index (intensity and prevalence of smoking) were observed in Asia than in Africa (p= 0.003 and p=0.001, respectively). A significant direct relationship was observed between the frequency of WT and smoking index (p= 0.001) while a significant inverse relationship between the prevalence of WT and malignant tumors of the parotid gland (p= 0.039) was also observed. In Africa, South Africa and Morocco had the highest prevalence of WT (13.4% and 11.5%, respectively) while Tanzania and Nigeria had the lowest prevalence of WT (3.6% and 0.0%, respectively). In Asia, Taiwan and South Korea had the highest prevalence of WT (46.6% and 38.8%, respectively) while Iran and Pakistan had the lowest prevalence of WT (7.6% and 3.5%, respectively). Conclusion: This review revealed that the high prevalence of WT in Asia could be due to a high smoking index in the continent. It suggests that the incidence of WT could be used as an alternative tool for monitoring the effect of smoking across countries.

The demographic and clinicopathological features of salivary gland tumors in Turkey

Aim: Salivary gland tumors (SGTs) are rare neoplasms thus, the local records are valuable to obtain the epidemiological overview. This study aimed to determine the demographic and clinicopathological features of SGTs in our clinic and compare the findings with the studies from Turkey and all over the world.Material and methods: The data of 185 patients who underwent surgery for SGT in The Department of Otorhinolaryngology-Head and Neck Surgery of a tertiary referral center between 2012 and 2017 were studied retrospectively. The demographic and clinicopathological features of the patients were recorded.Results: Among all patients with primary and secondary SGTs, the median age was 53 years, 54.6% of the patients were men. Patients with primary tumor constituted 96.8% of all cases. Malignancy rate was 14. Parotid gland was the most common location (90%). Nearly half of all primary tumors were diagnosed as pleomorphic adenoma (n=84, 46.9%). Mucoepidermoid carcinoma was the most common malign neoplasm of the parotid gland. There were only six patients (3.2%) that had secondary SGT.Conclusion: Pleomorphic adenoma and mucoepidermoid carcinoma were the most common benign and malign pathologies, respectively. The lowest malignancy rate and the highest rate of warthin tumor of the existing literature were the most conspicuous findings of our study. Although the frequency of the secondary SGTs is low, the possibility of metastasis should be considered especially for the patients above 65 years of age.

Clinical value of quantitative parameters by spectral CT in parotid gland tumor

This study aimed to investigate the value of normalized iodine concentration (NIC), spectral attenuation curve slope (SACS), area under curve (AUC), and iodine concentration difference (ICD) generated from spectral CT in the assessment of parotid gland tumors. Ninety-two patients with pathologically confirmed parotid gland tumors underwent arterial phase- and venous phase-enhanced CT in spectral CT. The patients were divided into the pleomor-phic adenoma group (group A), Warthin tumor group (group B), basal cell tumor group (group C), and malignant tumor group (group D). The SACS, AUC, NIC, ICD were measured and analyzed. Statistical analyses were performed by one-way ANOVA, and statistical significance was set at P<0.05. SACS(AP), AUC(AP), and NIC(AP) in group A were lower than those in other groups; SACS(VP) and AUC(VP) in group C were higher than those in other groups; NIC(AP) and NIC(VP) in group D were higher than those in other groups; and ICD in group B was a positive number. The difference in SACS(AP) and AUC(AP) in groups B and C, SACS(VP) and AUC(VP) in groups C and D, and ICD in groups A and C were not statistically significant. By contrast, the diffe-rence between the other groups was statistically significant (P<0.05). The difference in NIC(AP) between groups A and B and groups C and D and the difference in NIC(VP) between groups A and C, groups A and D, and groups B and C were statistically significant (P=0.005, 0.025, 0.002, 0.038, and 0.049, respectively). Multi-quantitative parameters from spectral CT might be helpful in differentiating various types of parotid gland tumors.

The diagnostic value of cytology in parotid Warthin's tumors: international multicenter series.

Warthin's tumor (WT) is a common benign salivary gland neoplasm with a negligible risk of malignant transformation. However, there is a risk of malignant tumors being misdiagnosed as WT on cytology and inappropriately managed conservatively. Patients from nine centers in Italy and the United Kingdom undergoing parotid surgery for cytologically diagnosed WT were included in this multicenter retrospective series. Definitive histology was compared with preoperative cytological diagnoses. Surgical complications were recorded. A total of 496 tumors were identified. In 88.9%, the final histological diagnosis was WT. In 21 cases (4.2%) a malignant neoplasm was diagnosed, which had been incorrectly labeled as WT on cytology. The risk of undiagnosed malignancy should be balanced against surgical risks when considering the management of WT. Although nonsurgical management remains an appropriate option, there may be a rationale for serial clinical or radiological evaluation if surgical excision is not performed.

Perfusion Computed Tomography Scan Imaging in Differentiation of Benign from Malignant Parotid Lesions.

Introduction The most common site of salivary gland tumors is the parotid gland. Computed tomography (CT), magnetic resonance imaging (MRI), and sonography are imaging modalities to differentiate benign from malignant parotid tumors. Objective The aim of this study is the evaluation of the diagnostic value of perfusion CT for differentiating histological categorization of benign and malignant parotid tumors. Methods A total of 29 patients with parotid neoplasms were enrolled in this study. Mean age and all CT perfusion variables (gradient and permeability, blood flow [BF], blood volume [BV], mean transit time [MTT], permeability surface [PS], maximum intensity projection [MIP], time-density curve [TDC], and time to peak [TTP]) were compared among three groups (malignant tumors [MTs], Warthin's tumor [WT] and pleomorphic adenomas [PA]). Results The mean age of the patients was 55.9 ± 14.1 (26–77), and 15 of them were male (51.7%). Eleven lesions were PAs [37.9%], 8 lesions were WTs (27.6%0 and 10 lesions (34.5%) were MTs (6 acinic cell carcinomas [ACCs], 3 adenocystic carcinomas [AdCCs], and 1 mucoepidermoid carcinoma [MEC]). The mean age of the patients with WTs was 62 ± 7.5 years; 52 ± 14.2 for patients with Pas, and 55.2 ± 17.2 for those with MTs ( p = 0.32). The mean MIP was 122.7 ± 12.2 in WT, while it was 80.5 ± 19.5 in PA, and 76.2 ± 27.1 in MTs ( p < 0.001); The mean MIP for WT was higher than for PAs and MTs; the values of MTs and PAs were not statistically different. The average of BF, BV, and curve peak were higher in WTs in comparison with the other two groups, and curve time 2 and TTP were higher in PAs in comparison with MTs. Conclusion Based on this study, perfusion CT of the parotid gland and its parameters can distinguish between benign and malignant parotid masses.

Parotid gland surgery as iatrogenic cause of facial nerve palsy – The role of adipocytokines in the pathology of parotid gland tumors

Facial nerve paresis is an important implicator of human quality of life. The are many known causes of facial nerve palsy but some still remain unknown (Bell's palsy). The most often cause of iatrogenic nerve damage is parotid gland surgery (facial nerve runs through the gland). The surgery is the treatment of choice in both benign and malignant tumors. Finding the biomarker of those tumors might influence the treatment decision and preserve the function of facial nerve. In present study we investigated the serum levels of selected adipocytokines in patients with parotid gland tumors (benign: 36 patients with pleomorphic adenoma (PA group), 25 patients with Warthin's tumor (WT group) and 11 with malignant tumors). The control group included 30 healthy individuals. The mean adiponectin concentration was significantly higher in benign tumor patients compared to controls in both genders in PA and WT groups. Total serum leptin levels in all of our patients (males and females) did not differ between groups. Serum visfatin concentrations were similar in all tumor patients in PA, WT and malignant groups and were significantly higher compared to controls. In summary we showed that adiponectin plays an “anti-malignant” role in benign tumors. Furthermore, leptin and visfatin seem to play an important role in the pathology of salivary gland tumors, although in both genders in a different manner. Our findings may have a potential impact on decision of treatment and therefore the quality of life related with facial nerve function.

Usefulness of ultrasound and fine needle aspiration cytology of major salivary gland lesions.

To assess the clinical value of ultrasound (US) and fine needle aspiration (FNA) of salivary gland lesions prior to surgery, for preoperative decision-making and long-term follow-up/outcome. We retrospectively analyzed the medical charts of 98 consecutive patients with major salivary gland lesions who were treated in a single medical from 2008 to 2017. Preoperative US and FNA was performed in all patients. Cytology results were compared with histopathological diagnoses. The correlation between preoperative US findings, cytology and histopathological diagnoses was assessed. Twenty-three specimens were histopathologically malignant, and 75 were diagnosed as benign. Three false-positive results diagnosed as malignant in cytology had a final histology of sialadenitis, pleomorphic adenoma and Warthin's tumor, respectively. In six cases, cytology yielded false-negative results. The overall accuracy of FNA in distinguishing benign from malignant lesions was 91%. Sensitivity was 70% and specificity 93%. There was no significant correlation between US features and final pathology, but larger size had some correlation with malignancy (p = 0.306). No complications were observed during or after performing FNA. FNA from salivary gland lesions is safe and in many cases can help in preoperative decision making or surgical planning. Hence, the results of FNA cytology should have an integral role in clinical decision-making and management of major salivary gland lesions. False-negative results do occur and therefore should be used only as an adjunctive measure.

Delayed enhancement in differential diagnosis of salivary gland neoplasm.

Multi-phasic Computed Tomography (CT) evaluation allows to study the enhancement features of parotid gland masses. The aim of our study was to evaluate the role of delayed enhancement in the characterization of different histologic types of parotid tumours. Forty-eight patients (22 male and 26 female) with at least one parotid gland tumor, were included in our study. Multi-phase CT images were obtained before and 30, 120 s and 8 minutes after intravenous contrast injection. The images were evaluated by two radiologists for lesion enhancement degree. A quantitative assessment was performed using a region of interest on each lesion and density changes between different phases were compared. The tumoral enhancement ratio was calculated between the 8 minutes delayed and the early (30 s) phase. The pathological diagnosis was confirmed in all patients after surgery. All patients had unilateral lesion for a total of 48 lesions. Twenty-eight were pleomorphic adenomas, 15 Warthin's tumours and 5 carcinomas. All Warthin tumours showed a rapid contrast enhancement at the early phase (30 sec) followed by a progressive wash-out during the delayed scans. Most of pleomorphic adenomas (89.2%) showed the highest density at the 8-minutes delayed phase. Malignant tumours showed slower contrast enhancement and 3 out of 5 (60%) showed a marked decrease at the 8 minutes delayed phase while the remaining 2 (40%), did not show any density reduction. The tumoral enhancement ratio was significantly different between Warthin tumours and pleomorphic adenomas and between Warthin's and malignant tumours. Multi-phasic CT examination with 8 minutes delayed acquisition has shown to be useful in parotid gland lesion differentiation.

Xanthogranulomatous Sialadenitis, an Uncommon Reactive Change is Often Associated with Warthin's Tumor.

Xanthogranulomatous sialadenitis (XGS) is rare in salivary glands and only reported in the literature as single cases. Here we report a cohort of four cases with XGS and summarize the clinicopathologic features of these cases. All four patients had persistent mass lesions concerning for neoplasm. In two patients (patient 1 and 3), the initial fine needle aspirations (FNAs) contained oncocytic cells consistent with or suspicious for Warthin's tumor, but follow-up FNAs showed only inflammation and/or debris indicating tumor infarction after FNA. All patients eventually had surgical resection. Histologically, all cases contained abundant macrophages with necrosis and fibroblastic proliferation. Warthin's tumor with a grossly identifiable tumor nodule (0.7cm) was noted in patient 1 and a microscopic focus (0.2cm) of Warthin's tumor was identified in patient 3. No identifiable tumor was observed in patient 2 and 4. There are a total of 10 XGS cases in the literature (including four from this series) and Warthin tumor was identified in 50% of reported cases of XGS, suggesting that XGS is an uncommon reactive process to spontaneous or procedure-induced infarction of Warthin tumor. As a diagnostic mimicker for malignancy, a thorough examination and generous sampling of surgical resection specimen is warranted, although a benign salivary gland neoplasm, commonly Warthin's tumor, is often identified.

Evaluation of Outcomes following Radiofrequency Ablation for Treatment of Parotid Tail Warthin Tumors.

To evaluate efficacy and safety of radiofrequency (RF) ablation for parotid Warthin tumor. From September 2016 to August 2017, 7 consecutive patients with biopsy-proven parotid Warthin tumors who did not undergo surgery presented with symptoms or cosmetic concerns and underwent US-guided percutaneous RF ablation treatment. RF ablation procedures were performed using the moving shot technique. US, contrast-enhanced CT, or MR imaging was performed 6-12 months after each procedure. Complications and cosmetic scale improvement after RF ablation were also evaluated. There was a significant reduction in mean tumor volume from 14.6 cm3 ± 13.1 (range, 1.9-35.5 cm3) to 0.8 cm3 ± 0.5 (range, 0.2-1.54 cm3) and a mean cosmetic scale improvement (from 4 to 1) on imaging studies 6-12 months after RF ablation compared with before RF ablation (P < .05). Volume reduction ratios at 1-2 months, 5-6 months, and 10-12 months after RF ablation were 51.2% ± 18.1%, 87.8% ± 10.6%, and 94.3% ± 2.0%. There was no facial nerve injury. One patient with parotitis and hematoma recovered in 1 week. RF ablation using the moving shot technique could be an effective and safe alternative treatment for parotid tail Warthin tumors in patients unsuitable for or unwilling to undergo surgical resection.

Multi-parametric MR imaging using pseudo-continuous arterial-spin labeling and diffusion-weighted MR imaging in differentiating subtypes of parotid tumors

PurposeTo evaluate multi-parametric MR imaging using pseudo-continuous arterial-spin labeling (pCASL) and diffusion-weighted imaging (DWI) in differentiating subtypes of parotid tumors. Material and methodsThis study was done on 61 consecutive patients (27 M, 34 F aged 15–75 ys: mean 42 ys) with parotid tumors that underwent pCASL and DWI with the calculation of tumor blood flow (TBF) and apparent diffusion coefficient (ADC). ResultsThe mean TBF and ADC of parotid malignancy (n = 20) (53.1 ± 6.9 mL/100 g/min and 0.66 ± 0.1 × 10−3 mm2/s) was a significant different (P = 0.001) than benign tumors (n = 41) (22.7 ± 2.7 mL/100 g/min and 1.28 ± 0.4 × 10−3 mm2/s) respectively. Multi-parametric TBF and ADC were used to differentiate malignant from benign tumors has an AUC (AUC) of 0.97, and the accuracy of 90%. There was a significant difference (P = 0.001) TBF between Warthin tumors (WT) (26.7 ± 9.7 mL/100 g/min) and malignancy. Selection of TBF of 30.5 mL/100 g/min to differentiate malignancy from WT revealed an AUC of 0.95 and the accuracy of 87%. There was a significant difference in TBF and ADC of pleomorphic adenomas (PA) from malignancy (P = 0.001). Multi-parametric TBF and ADC were used to differentiate PA from parotid malignancy revealed an AUC of 1.00. There was a significant difference in TBF and ADC of PA and WT (P = 0.001). Multi-parametric MRI using TBF and ADC used to differentiate PA from WT have an AUC of 0.99, and the accuracy of 92%. ConclusionMulti-parametric MR imaging using pCASL and DWI is useful for differentiating benign parotid tumors from parotid malignancy and PA from WT and TBF helps in discrimination of WT from parotid malignancy.