Pretherapeutic Predictive Factors for Histological High-Grade Parotid Gland Carcinoma.

OBJECTIVE: The histological grade of parotid gland carcinoma (PGC) is an important prognostic factor; however, the diagnosis prior to treatment has been challenging to make. This study aimed to investigate whether the pretreatment clinical findings, including hematological inflammatory, nutritional, and immune markers, could predict the histological grade of PGC. STUDY DESIGN: Retrospective study. METHODS: We retrospectively enrolled 111 patients with PGC and evaluated the correlation between histological grade and pretreatment clinical findings such as age, sex, tumor staging, facial nerve paralysis, pain or tenderness, adhesion to the surrounding tissues or tumor immobility, and hematological markers. RESULTS: Sixty patients (54%) were diagnosed with histological high-grade PGC. Univariate analysis revealed that age, T classification, N classification, TNM stage, facial nerve paralysis, adhesion/immobility, C-reactive protein (CRP), and CRP-to-albumin ratio (CAR) were significant predictors of PGC histological grade. On multivariate analysis, high T classification (T3, 4), high N classification (≥1), and elevated CRP (≥0.22 mg/dL) were independent predictors of high-grade PGC. CONCLUSIONS: Pretreatment T classification, N classification, and CRP are significant predictors of the histological grading of PGC. Our results are useful for treatment planning and obtaining appropriate informed consent from the patients before treatment. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:96-102, 2022.

Classification of parotid gland tumors by using multimodal MRI and deep learning.

Various MRI sequences have shown their potential to discriminate parotid gland tumors, including but not limited to T2 -weighted, postcontrast T1 -weighted, and diffusion-weighted images. In this study, we present a fully automatic system for the diagnosis of parotid gland tumors by using deep learning methods trained on multimodal MRI images. We used a two-dimensional convolution neural network, U-Net, to segment and classify parotid gland tumors. The U-Net model was trained with transfer learning, and a specific design of the batch distribution optimized the model accuracy. We also selected five combinations of MRI contrasts as the input data of the neural network and compared the classification accuracy of parotid gland tumors. The results indicated that the deep learning model with diffusion-related parameters performed better than those with structural MR images. The performance results (n = 85) of the diffusion-based model were as follows: accuracy of 0.81, 0.76, and 0.71, sensitivity of 0.83, 0.63, and 0.33, and specificity of 0.80, 0.84, and 0.87 for Warthin tumors, pleomorphic adenomas, and malignant tumors, respectively. Combining diffusion-weighted and contrast-enhanced T1 -weighted images did not improve the prediction accuracy. In summary, the proposed deep learning model could classify Warthin tumor and pleomorphic adenoma tumor but not malignant tumor.

Dynamic Contrast-Enhanced MRI to Differentiate Parotid Neoplasms Using Golden-Angle Radial Sparse Parallel Imaging.

BACKGROUND AND PURPOSE: Conventional imaging frequently shows overlapping features between benign and malignant parotid neoplasms. We investigated dynamic contrast-enhanced MR imaging using golden-angle radial sparse parallel imaging in differentiating parotid neoplasms. MATERIALS AND METHODS: For this retrospective study, 41 consecutive parotid neoplasms were imaged with dynamic contrast-enhanced MR imaging with golden-angle radial sparse parallel imaging using 1-mm in-plane resolution. The temporal resolution was 3.4 seconds for 78.2 seconds and 8.8 seconds for the remaining acquisition. Three readers retrospectively and independently created and classified time-intensity curves as follows: 1) continuous wash-in; 2) rapid wash-in, subsequent plateau; and 3) rapid wash-in with washout. Additionally, time-intensity curve-derived semiquantitative metrics normalized to the ipsilateral common carotid artery were recorded. Diagnostic performance for the prediction of neoplasm type and malignancy was assessed. Subset multivariate analysis (n = 32) combined semiquantitative time-intensity curve metrics with ADC values. RESULTS: Independent time-intensity curve classification of the 41 neoplasms produced moderate-to-substantial interreader agreement (κ = 0.50-0.79). The time-intensity curve classification threshold of ≥2 predicted malignancy with a positive predictive value of 56.0%-66.7%, and a negative predictive value of 92.0%-100%. The time-intensity curve classification threshold of <2 predicted pleomorphic adenoma with a positive predictive value of 87.0%-95.0% and a negative predictive value of 76.0%-95.0%. For all readers, type 2 and 3 curves were associated with malignant neoplasms (P < .001), and type 1 curves, with pleomorphic adenomas (P < .001). Semiquantitative analysis for malignancy prediction yielded an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.73-0.99). Combining time-to-maximum and ADC predicts pleomorphic adenoma better than either metric alone (P < .001). CONCLUSIONS: Golden-angle radial sparse parallel MR imaging allows high spatial and temporal resolution permeability characterization of parotid neoplasms, with a high negative predictive value for malignancy prediction. Combining time-to-maximum and ADC improves pleomorphic adenoma prediction compared with either metric alone.

UV Signature Mutations Reclassify Salivary High-grade Neuroendocrine Carcinomas as Occult Metastatic Cutaneous Merkel Cell Carcinomas.

Salivary high-grade neuroendocrine carcinomas (NECs) are rare, occur predominantly in the parotid gland, and are difficult to differentiate from metastatic cutaneous Merkel cell carcinomas (MCCs), which have overlapping morphologic, immunophenotypic, and molecular profiles. Oncogenic Merkel cell polyomavirus (MCPyV), found in 70% to 80% of MCCs, has also been reported in a few salivary NECs, but this is controversial. A promising biomarker to distinguish the 2 tumor types are UV signature mutations. UV signature mutations indicate a sun damage-induced mechanism of pathogenesis and recently have been found to be highly prevalent in MCPyV-negative MCCs but would be inconsistent with salivary origin. Here, we examine UV signature mutations as a molecular marker to distinguish primary salivary high-grade NEC from MCC. Whole exome DNA sequencing was performed on matched tumor-normal tissue from 4 MCPyV-negative high-grade salivary NECs with no other primary source identified, as well as 3 melanomas and 3 lung NECs as positive and negative controls, respectively. UV signature mutations were found in all salivary NECs, when defined as ≥60% of total mutations being C-to-T transitions at dipyrimidine sites, and when compared with known human cancer-related mutational signatures. The presence of UV signature mutations in salivary high-grade NECs strongly favors these to be occult metastatic MCCs. True salivary primary NECs are likely exceedingly rare. When a high-grade NEC is encountered in the salivary gland, the presence of UV signature mutations or MCPyV may be useful to exclude occult unknown primary MCC.

Intraparotid Facial Nerve Schwannoma in a Nine-Year-Old Patient: Diagnosis, Classification, and Surgical Approach Stages.

Intraparotid facial nerve schwannoma (IFNS) is rarely observed in children compared with adults. Only a few cases have been reported in the literature. After radiological imaging and fine needle aspiration biopsy, an IFNS diagnosis may be skipped and confused with pleomorphic adenoma, which has a high prevalence among patients who have a mass in the parotid gland. The probability of IFNS can be recognized by a close relation between the mass and the facial nerve during the application of parotidectomy and by the frozen biopsy of the mass. The surgeon evaluates the mass and faces with surgical mass excison and facial nerve reconstruction according to the relation between the mass and the facial nerve because there is no diagnostic method for the presurgery diagnosis of IFNS. Therefore, the surgeon should be prepared for the possibility of functional lossin the facial nerve during parotidectomy. This article presents the case of a 9-year-old patient with an IFNS diagnosis who had a surgical operation in our clinic, and the algorithm designed according to the literature for the diagnosis and surgical classification of IFNS, as well as the approaches to facial nerve reconstruction.

Risk of high-grade malignancy in parotid gland tumors as classified by the Milan System for Reporting Salivary Gland Cytopathology.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (Milan System) has previously shown its diagnostic utility by categorizing the seven cytology findings in salivary gland lesions. However, there has been lack of study about the risk of high-grade malignancy in the cytology diagnosis based on the Milan System. Thus, we tried to identify the diagnostic ability of the Milan System for high-grade malignancy and to suggest an improved diagnostic approach for preoperative estimation of high-grade malignancy using the Milan System. METHODS: A total of 413 patients with parotid gland tumors, who had undergone surgical resection from 2011 to 2015 were included in the present study retrospectively. Cytopathology was reclassified according to the Milan System by two independent reviewers. The outcomes were risk of malignancy and risk of high-grade malignancy. The diagnostic performance of the Milan System category [Malignant] for detecting high-grade malignancy was calculated. RESULTS: The risk of malignancy was 83.3% and 100% in the Milan System categories [Suspicious for Malignancy] and [Malignant], respectively. Meanwhile, the risk of high-grade malignancy was 16.7% and 55.9% in these two categories. Disease-free survival of patients with high-grade malignancy was significantly worse than those with low- and intermediate-grade malignancy. Union combining the Milan System category [Malignant] with the presence of nodal metastasis suggested high-grade malignancy with an acceptable diagnostic sensitivity (0.889-0.963) and negative predictive value (0.900-0.966). CONCLUSIONS: The Milan System category [Malignant] with the presence of nodal metastasis suggested parotid gland tumors as high-grade malignancy in a pretreatment setting.

Application of the Milan System for Risk Stratification and Its Comparison with a Previous Reporting System of Parotid Gland Cytopathology in a Tertiary Care Centre.

OBJECTIVE: To compare the recently proposed Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) with the four-tiered reporting system (FTRS) followed at our institute. METHODS: Parotid gland fine-needle aspirates reported over a period of 5 years were analysed. These aspirates had been placed into 4 categories according to the FTRS: unsatisfactory (UNS), no evidence of malignancy/negative (NEG), inconclusive for malignancy (INC), and diagnostic for malignancy/positive (POS). Aspirates with follow-up histopathology were then categorized according to the MSRSGC as follows: non-diagnostic, non-neoplastic, atypia of unde-termined significance (AUS), neoplasm, suspicious for malignancy, and malignant. The risk of malignancy (ROM) was calculated. RESULTS: A total of 893 parotid region aspirates were evaluated and histopathology was available for 190 cases (21%). ROM in MSRSGC groups, namely non-diagnostic, non-neoplastic, AUS, neoplasm, suspicious for malignant neoplasm, and malignant, was 44, 8, 0, 12, 81 and 100%, respectively. ROM in FTRS groups, namely UNS, NEG, INC, and POS, was 45, 13, 67 and 100%, respectively. CONCLUSIONS: MSRGC and FTRS are comparable with respect to the ROM across groups. Compared to FTRS, the further subcategorisation of the non-malignant group, the use of specific nomenclature, and the reproducibility of MSRGC provide proper risk stratification, thereby guiding better management and resulting in improved patient care.

Application of Sal classification to parotid gland fine-needle aspiration cytology: 10-year retrospective analysis of 312 patients.

BACKGROUND: The accuracy of fine-needle aspiration biopsy (FNAB) is controversial in parotid tumors. We aimed to compare FNAB results with the final histopathological diagnosis and to apply the "Sal classification" to our data and discuss its results and its place in parotid gland cytology. METHODS: The FNAB cytological findings and final histological diagnosis were assessed retrospectively in 2 different scenarios based on the distribution of nondefinitive cytology, and we applied the Sal classification and determined malignancy rate, sensitivity, and specificity for each category. RESULTS: In 2 different scenarios FNAB sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were found to be 81%, 87%, 54.7%, and 96.1%; and 65.3%, 100%, 100%, and 96.1%, respectively. The malignancy rates and sensitivity and specificity were also calculated and discussed for each Sal category. CONCLUSION: We believe that the Sal classification has a great potential to be a useful tool in classification of parotid gland cytology.

Adenoma pleomorfo parotídeo gigante: a propósito de un caso clínico / Giant parotid pleomorphic adenoma: a case report

El adenoma pleomorfo es el tumor benigno más frecuente de las glándulas salivales, con mayor predilección por la glándula parótida. Se presenta un caso clínico de paciente femenino de 53 años de edad, con aumento de volumen en región parotídea y geniana derecha de15 × 12 centímetros, de ocho años de evolución, la tomografía simple de la región presenta tumoración parotídea bien delimitada, la cual afecta lóbulo superficial y profundo de la glándula parótida derecha, la biopsia incisional confi rmó el diagnóstico histopatológico de adenoma pleomorfo por lo cual se realiza parotidectomía total sin preservación del nervio facial.

Pleomorphic adenoma is the most common benign tumor of the salivaryglands, with greater predilection for the parotid gland. We presentthe case of a 53-year-old female patient with a 15 x 12 cm increasein volume in the parotid and right genial region with eight years ofevolution. A simple CT scan of the region revealed a well-defi ned parotidtumor aff ecting the superfi cial and deep lobe of the right parotidgland. An incisional biopsy confi rmed the histopathological diagnosisof pleomorphic adenoma, for which reason a total parotidectomy wasperformed without preservation of the facial nerve.

Adenoma pleomorfo parotídeo: informe de un caso de ubicación atípica / Parotid pleomorphic adenoma: report of a case with atypical location

Objetivo: presentar un caso atípico de adenoma plemorfo. Caso clínico: se expone el caso clínico y la técnica quirúrgica empleada en una paciente con adenoma plemorfo ubicado en el lóbulo profundo, con una relación atípica del tumor y las ramas terminales del nervio facial. Conclusión: los procedimientos conservadores como la tumorectomía, demostraron un porcentaje de recidiva nueve veces mayor que el de la parotidectomía superficial o total.

Parotid Gland Tumors and the Facial Nerve.

Various types of parotid gland tumors are discussed from nonneoplastic to both benign and malignant neoplasms. The anatomic relationship of the facial nerve is discussed as it exits the stylomastoid foramen and courses through the parotid gland. The effect of certain tumors on facial nerve function is also characterized. Details on which types of parotid tumors are more likely to affect facial nerve function and different prognostic predictors of return to function are evaluated. In addition, the prognostic value of tumor size and histologic type of parotid tumor is included.

Feasibility of a novel classification for parotid gland cytology: A retrospective review of 512 cytology reports taken from 4 United Kingdom general hospitals.

BACKGROUND: A novel classification for parotid cytology has been previously proposed. The purpose of this study was to assess the feasibility and clinical relevance of this classification. METHOD: Between 2010 and 2013, cytology reports from 4 United Kingdom general hospitals were retrospectively classified and compared to histological and clinical outcomes. RESULTS: Based on the cytology reports of 512 patients, we revised our previous "P" system to a "Sal" (salivary) classification to encompass all cytologic outcomes. The percentage of patients with a final diagnosis of malignancy according to each category heading were: Sal 1 (inadequate) 7.9%; Sal 2I (nonneoplastic) 10%; Sal 2N (benign neoplastic) 1.4%; Sal 3 (atypical) 20.4%; Sal 4 (suspicious) 52.6%; Sal 5P (primary salivary gland malignancy) 71.4%; Sal 5NOS (malignancy not otherwise specified) 100%; and Sal 5M (metastasis) 91.7%. CONCLUSION: By stratifying the probability of encountering a malignant neoplasm, the classification could guide clinical management decisions. A future prospective study is warranted. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1708-1716, 2016.

Histological reclassification of parotid gland carcinomas: importance for clinicians.

Reassessment of histological specimens of salivary gland carcinomas is associated with a change of primary diagnosis in a significant number of patients. The authors evaluated the relation between reclassification/verification of histological diagnosis and the clinical course of parotid gland carcinomas. Histological and immunohistochemical examinations of 111 specimens of parotid gland carcinomas operated on during the years 1992-2010 were revised and in some cases supplemented with cytogenetic tests (FISH), to verify the diagnosis and potentially reclassify the tumours. Analysis of the clinical documentation and follow-up data of patients whose diagnosis was changed was then carried out. The prognostic factors taken into account in the evaluation of the clinical course included the T and N stage, the tumour grade and the extent of resection. The primary diagnosis was changed on review in 28 patients (25.2 %). In 16 patients, the change involved a different histological type of cancer. In six cases, what was thought to be a primary salivary gland cancer was reclassified as a secondary tumour. In four other cases, the change was made from a malignant to a benign tumour and in one case to a non-neoplastic lesion (necrotizing sialometaplasia). Additionally, in two patients with carcinoma ex pleomorphic adenoma, the malignant component was found to be of in situ type. A potentially atypical clinical course was observed in 4 out of 28 patients whose diagnosis was changed. In the case of 2 patients, the course of disease was more aggressive (dissemination, death) than predicted and less aggressive in rest of the patients. Histological reclassification/verification of parotid gland carcinomas can explain the cause of an atypical clinical course in some patients and sometimes enables doctors to implement a change in therapy.

Clasificación pronóstica de los tumores malignos de glándula parótida / Forecast clasification for malignant tumors of the parotid

Objetivo. La clasificación histológica de la Organización Mundial de la Salud (OMS) junto con mejores estudios de imagen aportan información relevante para el manejo de los cánceres de parótida. Sin embargo, su pronóstico depende de otros factores diferentes de la histología y la extensión tumoral. El presente trabajo valora la utilidad de la clasificación pronóstica de Vander Poorten creada en 1999 de los cánceres parotídeos que incluye todos estos factores en los pacientes de nuestro medio. Métodos. Seguimiento de 19 pacientes con carcinomas de parótida distintos de tumores linfoideos o metástasis intraparotídeas entre los años 1998 y 2012. Se obtuvo su índice pronóstico a partir de las fórmulas propuestas por Vander Poorten, que incluyen los factores de edad, tamaño tumoral, afectación ganglionar, invasión cutánea, afectación del nervio facial, crecimiento perineural y márgenes de resección, antes de la cirugía (PS1) y después (PS2). Se relacionó la supervivencia global a los 5 años de cada paciente a partir de su inclusión en alguno de los 4 grupos de riesgo definidos. Resultados. La estratificación de riesgo de Vander Poorten según los resultados PS2 se distribuyó en grupos de riesgo (GR) 1 (3 pacientes, 15,7%), 2 (5 pacientes, 26,3%), 3 (un paciente, 5,8%) y 4 (10 pacientes, 52,2%). Los 6 pacientes que fallecieron durante el seguimiento pertenecían al GR4. De los 4 supervivientes del GR4 solo uno ha superado el seguimiento de 5 años. La comparación de las medias que relacionan las variables de resultado pretratamiento (PS1) y postratamiento (PS2) mostró una mejor supervivencia global en los pacientes con valores de PS1 < 4,5 y PS2 < 4,9, mientras que la mortalidad fue mayor a partir de los índices de PS1 > 6,5 y PS2 > 7,7. Conclusiones. El índice de Vander Poorten es aplicable en áreas hospitalarias con escaso número de carcinomas de parótida. Permite establecer un pronóstico de supervivencia más certero sobre pacientes individuales (AU)

Objective. The histological classification of the World Health Organization (WHO), along with improved imaging studies, provide relevant information for the management of parotid carcinomas. However, the prognosis depends on factors other than histology and tumor extension. This article evaluates the usefulness of a prognostic classification of parotid cancers, including these factors in patients in a hospital area. Methods. A follow-up was conducted on 19 patients with parotid carcinomas, excluding lymphoid tumors or intra-parotid metastases, between 1998 and 2012. The prognostic index was obtained from the formulas proposed by Vander Poorten, with factors including age, tumor size, lymph node involvement, skin invasion, facial nerve involvement, perineural growth and margins of resection, before surgery (PS1) and after (PS2). Overall survival was related to 5 years for each patient based on their inclusion in any of the 4 risk groups defined. Results. Risk stratification based on the results Vander Poorten PS2 was distributed into Risk Groups (GR) 1 (3 patients, 15.7%), 2 (5 patients, 26.3%), 3 (1 patient, 5.8%) and 4 (10 patients, 52.2%). The 6 patients who died during follow-up belonged to GR4. Only one of the 4 patients belonging to GR4 has exceeded the 5-year survival up to the current time. The comparison of the values that relate the pretreatment (PS1) and after treatment (PS2) results showed overall survival in patients with PS1 < 4.5 and PS2 < 4.9, whereas mortality was greater with indices of PS1 > 6.5 and PS2 > 7.7. Conclusions. Vander Poorten index can be applied in hospital areas with small numbers of parotid carcinomas. It enables a more accurate prognosis for individual patients (AU)

Oncocitoma: caso clínico / Oncocytoma: a clinical case

El oncocitoma es un tumor benigno que afecta varios órganos como tiroides, paratiroides, riñón y glándulas salivales, que consiste en la proliferación de células oncocíticas producidas por una gran hiperplasia mitocondrial. El oncocitoma representa menos del 1 por ciento de todos lostumores de las gandulas salivales. Cuando en estudios por imágenes de glándula parótida se observen múltiples pequeños nódulos con unamasa sólida o quística, el diagnóstico de oncocitoma debe ser considerado, especialmente en pacientes de sesenta o más años. El objetivo de este artículo es la presentación de un caso de oncocitoma y analizar el estado de arte de los casos reportados en la temática.

The oncocytoma is a benign neoplastic tumor that occurs in several organs, including the thyroid gland, parathyroid gland, kidneys, and salivary glands consisting of a proliferation of oncocytic cells produced by a large mitochondrial hyperplasia. The oncocytoma accounts for less than 1% of the whole salivary gland tumors.When multiple small nodules are found in the parotid gland with a large solid or cystic mass that is evident on imaging, a diagnosis of oncocytoma should be considered, particularly in patients of sixty years of age or older. The objective of this article is the presentation of a case of oncocytoma and the state of art of reported cases in this field.

Warthin-like Mucoepidermoid Carcinoma: A Combined Study of Fluorescence In Situ Hybridization and Whole-slide Imaging.

There has been some debate as to whether a subset of metaplastic Warthin tumors (mWTs) harbor the mucoepidermoid carcinoma (MEC)-associated CRTC1-MAML2 fusion. We analyzed 15 tumors originally diagnosed as mWT (mWT-like tumors), 2 of which had concurrent MECs. We looked for the CRTC1/3-MAML2 fusion transcripts and performed immunohistochemistry for p63 and fluorescence in situ hybridization (FISH) for the MAML2 split. To localize MAML2 split-positive cells at the cellular level, whole tumor tissue sections were digitalized (whole-slide imaging [WSI]). The CRTC1-MAML2, but not CRTC3-MAML2 was detected in 5/15 mWT-like tumors. FISH-WSI results showed that all epithelial cells harbored the MAML2 split in fusion-positive mWT-like tumors and were totally negative in fusion-negative mWT-like tumors. A review of the hematoxylin and eosin-stained slides showed that morphology of the "metaplastic" epithelium was virtually indistinguishable between fusion-positive and fusion-negative tumors. However, oncocytic bilayered tumor epithelium, characteristic to typical WT, was always found somewhere in the fusion-negative tumors but not in the fusion-positive tumors. This distinguishing histologic finding enabled 5 pathologists to easily differentiate the 2 tumor groups with 100% accuracy. The age and sex distribution of fusion-positive mWT-like tumor cases was similar to that of fusion-positive MEC cases and significantly different from those of fusion-negative mWT-like tumor and typical WT cases. In addition, only fusion-positive mWT-like tumors possessed concurrent low-grade MECs. In conclusion, a subset of mWT-like tumors were positive for the CRTC1-MAML2 fusion and had many features that are more in accord with MEC than with WT. The term Warthin-like MEC should be considered for fusion-positive mWT-like tumors.

A more appropriate clinical classification of benign parotid tumors: investigation of 425 cases.

CONCLUSIONS: It is appropriate to clinically classify benign parotid tumors into three groups, i.e. superficial tumors, deep tumors, and lower pole tumors. OBJECTIVE: It is important to classify benign parotid tumors based on location when deciding the surgical strategy and conducting clinical research. In this study, we examined a classification of benign parotid tumors that was useful for clinical practice. METHODS: We studied 425 patients with benign parotid tumors who underwent surgery at our hospital. Their age, gender, tumor histopathology, maximum tumor diameter, postoperative facial nerve paresis, operating time, and blood loss were investigated after classifying the tumors as superficial tumors, deep tumors, or lower pole tumors. We also investigated the same parameters after dividing the lower pole tumors into superficial and deep types. RESULTS: Lower pole tumors had distinct characteristics from superficial and deep tumors. The incidence of facial nerve paresis was significantly higher and the operating time was significantly longer for deep tumors than for either superficial or lower pole tumors, while there were no significant differences between superficial and lower pole tumors. In addition, there were no significant differences in any of the parameters between the superficial and deep types of lower pole tumor.

Two-phase computed tomography study of warthin tumor of parotid gland: differentiation from other parotid gland tumors and its pathologic explanation.

OBJECTIVE: The objective of this study was to define the radiological characteristics of 2-phase computed tomography (CT) of parotid gland Warthin tumors (WTs) with a pathologic basis for these findings. METHODS: We prospectively enrolled 116 patients with parotid gland tumor who underwent preoperative 2-phase CT scans(scanning delays of 30 and 120 seconds). The attenuation changes and enhancement patterns were analyzed according to pathology. We also evaluated size-matched samples of WTs and pleomorphic adenoma by staining CD31, vascular endothelial growth factor-receptor 2, collagen IV, and smooth muscle actin. RESULTS: Computed tomography numbers in WTs were significantly higher than those in other tumors in early-phase scans and lower in delayed scans. Pathologically, CD31(+) blood vessel area was significantly higher in WTs than in pleomorphic adenomas. In addition, WTs had an extensive capillary network and many leaky blood vessels. CONCLUSIONS: The enhancement pattern of early fill-in and early washout is the typical finding of WTs on 2-phase CT scans, which may be attributed pathologically to abundant blood vessel and extensive capillary network.

Is sonoelastography a helpful method for evaluation of parotid tumors?

Sonoelastography is a novel technique, useful in a noninvasive assessment of lesions in multiple organs. The aim of the study was to examine whether the combination of conventional ultrasonography (US) with sonoelastography might improve the reliability of parotid tumor evaluation. Fourty-three consecutive patients with parotid tumors were surgically treated at a single tertiary center at the Department of Otolaryngology, Head and Neck Surgery. The sample included 27 women and 16 men, aged 15-80 (the mean age = 54 years). The reference group constituted of 54 healthy volunteers. High resolution grayscale ultrasonography (US) was performed preoperatively using a 15 MHz linear array transducer. Elastograms (ES) were scored by the conventional Ueno 5-point scale from ES1 (blue-soft) to ES5 (the entire lesion and surrounding area shaded red-stiff). In addition, detailed stiffness values in kPa were collected. The group consisted of 33 patients with benign and 10 patients with malignant tumors. The mean stiffness value was 146.6 kPa in 10 malignant tumors (mostly ES4) and 88.7 kPa in 33 benign tumors (mostly ES2 and ES3). The differences in tissue stiffness between normal parotid parenchyma in the reference group and the mean value for all tumors in the examined group were statistically significant (p < 0.001), and so was the case with the differences between the benign and malignant tumors (p < 0.001). Low stiffness scores (ES1,2) were found in 2 malignant and 15 benign tumors while high scores (ES3,4) were found in 8 malignancies and 18 benign tumors. Sonoelastography overlapping elasticity to the grayscale images supports additional informations. Preferential selection of the lesions characterized by high stiffness (ES4) improves the differential diagnosis of parotid tumors but the large degree of uncertainty of this method should also be pointed out.