Top PDF CT of parotid tumors

CT of parotid tumors

CT of parotid tumors

In two of the three patients with intermediate dens ity parotid g land s, th e tumo rs were easily re cognized, and, in th e other patient with a parotid cyst, the margin of th e mass co[r]

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CT Features of Parotid Gland Oncocytomas: A Study of 10 Cases and Literature Review

CT Features of Parotid Gland Oncocytomas: A Study of 10 Cases and Literature Review

SUMMARY: Oncocytomas of the salivary glands are rare benign epithelial tumors which occur most commonly in the parotid gland. The aim of our study was to characterize the clinical-radiologic- pathologic spectrum of parotid oncocytomas in a series of 10 cases seen in our institution between January 2003 and November 2008. The CT features of parotid oncocytomas in the largest imaging series of this rare but important benign lesion include a well-defined enhancing tumor with a “deform- able” appearance when large, and a non-enhancing curvilinear cleft or cystic component. These CT findings are potentially helpful in distinguishing these benign lesions from other parotid tumors in clinical scenarios that preclude surgical resection or when biopsy results are non-diagnostic. Further studies are advocated to validate the specificity and positive predictive value of these imaging features.
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<p>A Preliminary Study of CT Texture Analysis for Characterizing Epithelial Tumors of the&nbsp;Parotid Gland</p>

<p>A Preliminary Study of CT Texture Analysis for Characterizing Epithelial Tumors of the&nbsp;Parotid Gland</p>

Generally, parotid tumors are present in two forms: a well-de fi ned and mobile lump or a lump with signi fi cant accompanying symptoms, like pain, rapid growth, facial paralysis or metastasis. The former features are indications of benign lesions, while the latter features are indications of malignancy. However, quite a few malignancies have an indolent nature and may be clinically indistinguishable from benign tumors. As indolent lesions may masquerade as benign tumors, the de fi nitive histology sometimes may not be available until after surgical resection. At present, partial parotidectomy or super fi cial parotidectomy is usually applied for benign tumors and partial super fi cial parotidectomy (PSP) is the most common surgical proce- dure for PA, while total parotidectomy with or without facial nerve removal is applied to malignant tumors. 2,3 Consequently, preoperative diagnosis of parotid gland tumors is of great importance in view of optimizing the individualized surgical plan. Differentiation based on clin- ical symptoms is dif fi cult because of the obvious overlap among different tumors.
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Diagnostic accuracy of Magnetic Resonance Imaging to differentiate benign and Malignant Parotid Gland Tumors

Diagnostic accuracy of Magnetic Resonance Imaging to differentiate benign and Malignant Parotid Gland Tumors

Although variable results have been found in the international literature but overall our results are comparable to most of them. Bartels S. and colleagues retrospectively selected forty-eight patients of parotid tumors of any histology out of ive hundred and eighty six (13 investigated with CT, 35 with MRI); 23 (48%) of the lesions were malignant and 25 (52%) were benign. MRI, CT, and FNA misclassi ied 17%, 46%, and 21% of the lesions respectively, indicating MRI being the least contributor in misdiagnosis thus comparable to our results which showed MRI misinterpreting 10 % of the patients. Sensitivity, speci icity and accuracy for detecting malignant lesions on MRI and FNA were as follows: MRI (88%, 77%, 83%) and FNA (83%, 86%, 85%) respectively. The investigators concluded that imaging and FNA are comparable in their ability to correctly identify malignant parotid lesions preoperatively and that combining the two modalities yields no advantage in terms of sensitivity, speci icity, and accuracy of a malignant tumor diagnosis. The results also added that MRI is the irst test of choice, because it was not only as effective as FNAB at labeling the suspicion of malignancy but also provide detailed anatomical information about the extent of the primary tumor and adjacent lymph nodes [28].
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Perfusion CT Imaging of Brain Tumors: An Overview

Perfusion CT Imaging of Brain Tumors: An Overview

Recent advances in brain tumor treatment have led to aggres- sive management strategies with combinations of surgery, chemotherapy, and radiation therapy based on the location and histologic type of tumor. In particular, various forms of radiation therapy, including stereotactic radiosurgery, high- dose external beam radiation, and brachytherapy, have be- come important therapeutic adjuncts. Patient survival and quality of life are correlated with response to therapy, tumor recurrence, and also adverse effects of radiation therapy, such as radiation necrosis. Differentiating recurrent tumors from radiation necrosis on imaging studies has always been an im- portant clinical imperative because the management of these 2 entities is different. The problem is confounded by the fact that there is often a mixture of tumor with necrosis. Conven- tional MR imaging features and MR spectroscopic imaging have been used to differentiate radiation necrosis from recur- rent tumors with mixed success. 27,28 Various forms of meta-
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Low-grade cribriform cystadenocarcinoma of salivary glands: report of two cases and review of the literature

Low-grade cribriform cystadenocarcinoma of salivary glands: report of two cases and review of the literature

Abstract: Low-grade cribriform cystadenocarcinoma (LGCCC) is a recently described rare tumor of salivary gland which exhibits clinically indolent behavior. This tumor predominantly consists of intraductal components and frequently exhibits papillary-cystic or cribriform proliferation pattern. Considering the histological features of LGCCC, it should be distinguished with papillocystic variant of acinic cell carcinoma, conventional salivary duct carcinoma, cystadenocarcinoma, polymorphous low-grade adenocarcinoma, carcinoma ex pleomorphic adenoma and mammary analogue secretory carcinoma. Herein, we presented two cases of LGCCC. One arose in the left parotid region in a 48-year-old male, and the other one arose in the right parotid gland in a 59-year-old female. For both cases, immunohistochemically, the luminal tumor cells showed diffuse expression of CK and S100; p63 and smooth muscle actin displayed a continuous rim of myoepithelial cells around all tumor islets; no myoepithelial cells were admixed with the luminal cells. Both patients were alive with no tumor recurrence or metastasis at follow-up. Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/ vs/2593621568999135
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Three dimensional CT of central lung tumors

Three dimensional CT of central lung tumors

3D evaluations suggested bronchial invasion in 317 cases: gross tumor invasion was bronchoscopically confirmed in one of these cases one true positive case: left main bronchus; two false[r]

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CT and Angiography of Primary Extradural Juxtasellar Tumors

CT and Angiography of Primary Extradural Juxtasellar Tumors

The tumors in our series could be differentiated by the presence or absence of tumor calcification , degree and character of contrast enhancement, degree and location of bone erosion, an[r]

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Dysembryoplastic neuroepithelial tumors: MR and CT evaluation

Dysembryoplastic neuroepithelial tumors: MR and CT evaluation

with chronic focal epilepsy. The neuroradiologic characterization of such lesions is essential for the treatment of these patients because it aids in identifying those who are likely to benefit from epilepsy surgery. Following hippocampal scle- rosis, benign tumors are the second most frequent brain lesions that are associated with epilepsy (10). The high prevalence of gang- liogliomas in patients with chronic focal epi- lepsy contrasts with the fact that they constitute only 0.4% to 1.3% of all brain tumors in general neurosurgical series (23, 24). In our epilepsy surgery series, which presently includes 469 resection specimens, there were 138 tumors, including 17 DNTs (13%), 62 gangliogliomas (45%), and 59 astrocytomas (mixed gliomas and oligodendrogliomas) (42%).
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Expression of VEGF₁₆₅b, VEGFR1, VEGFR2 and CD34 in benign and malignant tumors of parotid glands

Expression of VEGF₁₆₅b, VEGFR1, VEGFR2 and CD34 in benign and malignant tumors of parotid glands

Among the molecules which were determined in our study, VEGFR1 expression correlated with the T score in malignant tumors. According to Younes et al., AEE788, a dual inhibitor of EGF and VEGF receptor tyrosine ki- nases, increased tumor and cell apoptosis, and decreased microvessel density, which correlated with a decrease in the incidence of vascular metastasis of salivary adenoid cystic carcinoma. This data showed that both receptors, EGFR and VEGFR, can be molecular targets for therapy

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Outcome analysis of 215 patients with parotid gland tumors: a retrospective cohort analysis

Outcome analysis of 215 patients with parotid gland tumors: a retrospective cohort analysis

between 1960 and 1998 for malignant parotid tumors and found that histopathological subtype, age and sex were also significant clinical predictors for survival [4]. Other studies have demonstrated the importance of regional lymph node involvement, positive surgical margins, perineural invasion, and facial nerve palsy as significant clinical predictors of outcome [4 – 7]. Recent studies have investigated molecular prognosticators asso- ciated with less favorable outcomes in those with salivary gland malignancy [8 – 11]. Interpretation of the literature is often difficult as patients in a given case series have typic- ally been treated over extended periods of time, and using non-uniform treatment modalities [12].
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Quantitative Evaluation of Pulmonary Emphysema Using Magnetic Resonance Imaging and x-ray Computed Tomography

Quantitative Evaluation of Pulmonary Emphysema Using Magnetic Resonance Imaging and x-ray Computed Tomography

tant since using small kernel will not remove the vessels con- nected to nodules and large kernel will affect the measured nodules volumes. Since lung tumors can vary in size consider- ably, it is difficult to find a fixed size structure kernel that is suitable to segment nodules with different sizes. 7 Conse- quently, the morphological operators may fail to prevent leak- age into adjacent anatomic structures. Tran et al. 8 used a semiautomated nodule segmentation by threshold halfway between the a user supplied seed point and the image back- goround. Then, using region growing the algorithm segment all connected voxels to the seed point which has an attenua- tion greater than the threshold. Then, using morphologic oper- ations, the algorithm tries to separate nodules from adjacent anatomy. To overcome the possible morphologic operator failure, the user manually draw a wall contour to stop region growing from leaking into adjacent anatomy. They evaluated their algorithm with 32 lesions from 15 patients. Each of the patients had a baseline and two follow-up scans leading to 30 response classifications. They found that 1D, 2D, and 3D measuremnts were in agreement in 21, 1D and 3D measurements were in agreement in 29, and 2D and 3D measurements were in agreement in 23 of 30 classifications. The level of agreement was evaluated using Kappa statistics K for 1D compared to 3D [K ¼ 0.739 6 0.345 (visits 1, 2) and 0.273 6 0.323 (visits 2, 3)], for 2D compared with 3D, (K ¼ 0.655 6 0.325 (visits 1, 2) and 0.200 6 0.208 (visits 2, 3). Moltz et al. 9 presented a lung nodules segmentation algorithm that combines a threshold-based approach with model-based morphological processing. Since mophological operators are not sufficient to separate lung nodules from ad- jacent anatomic structures, they incorporated manual interac- tive correction to contorol the erosion. Their algorithm was evaluated on 101 lung nodules from 28 patient. In 88% were classified visually as acceptable
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Plasmacytoid myoepithelioma of minor salivary glands: report of case with emphasis in the immunohistochemical findings

Plasmacytoid myoepithelioma of minor salivary glands: report of case with emphasis in the immunohistochemical findings

myogenic differentiation, even though it is positive for pan-cytokeratin [24,25]. It has been demonstrated that cultured cell lines derived from PMs express a-SMA, but this is not so for the tumoral cells of paraffin- embedded tissue. These findings suggest that plasmacy- toid cells show full myoepithelial differentiation in vitro . Thus, they should be considered myoepithelial-like cells, and the lack of myogenic differentiation in vivo could be due to an inhibitory process mediated by the extracellu- lar matrix [24]. Supporting this theory, the neoplastic cells were negative for a -SMA In the present case. On the other hand, immunopositivity for myogenic markers in PM has been demonstrated by Scarpellini et al., [25] suggesting that these plasmacytoid cells might exhibit distinct myoepithelial phenotypes in different tumors.
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Perfusion CT for Head and Neck Tumors: Pilot Study

Perfusion CT for Head and Neck Tumors: Pilot Study

on two occasions, or between the ipsilateral and con- tralateral ICA as the input artery. Although the sta- tistical test failed to show a significant difference in these mentioned parameters, it was able to reveal significant differences in measurements between pa- tients for most structures. The primary-site lesions included retromolar trigone squamous cell cancer, gingival squamous cell cancer, squamous cell cancer on the floor of the mouth, recurrent squamous cell cancer of the larynx, orbital alveolar rhabdomyosar- coma, parotid pleomorphic adenoma, atypical vascu- lar proliferation in the vocal cords, fat necrosis and inflammation, and active chronic inflammation of the hypopharynx. None of the lesions had necrotic areas on contrast-enhanced diagnostic CT. No adverse re- actions to the contrast agent were encountered. Not
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CT-guided laser probe for ablation of brain tumors

CT-guided laser probe for ablation of brain tumors

Since lasers do not penetrate deepy into tissues and heat does not conduct very well in tissues, laser ablations are usually not a good choice for ablating large volumes of tissue such az large or multiple liver tumors. RF and microwave ablation techniques are better suited for such applications.

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No evidence for human papillomavirus having a causal role in salivary gland tumors

No evidence for human papillomavirus having a causal role in salivary gland tumors

indicated that there are major differences in mutation frequencies between different salivary gland tumor sub- types, where none or few mutations were found in mucoepidermoid, adenoid cystic and acinic cell subtypes [9], suggesting that other factors such as e.g. a viral in- fection may be the causative factor. There are a handful small studies that have shown an association between HPV infection and certain salivary gland malignancies, however, reported HPV prevalence varied to a great ex- tent, as summarized in Additional file 1: Table S1 [10– 17]. Moreover, these studies included only a small sam- ple size, and most studies only included one or few spe- cific subtypes of salivary gland tumors with very few samples in each subgroup, thus missing proper control groups. In this study we investigated the occurrence of HPV (defined as being HPV DNA positive and overex- pressing p16 INK4a ) in, to our knowledge, the largest co- hort of parotid salivary gland tumors, including 12 different subtypes, in patients diagnosed between 2000-2009 in the counties of Stockholm and Gotland.
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Case Report Multiple bilateral Warthin’s tumors of the parotid glands with pleomorphic adenoma: a case report

Case Report Multiple bilateral Warthin’s tumors of the parotid glands with pleomorphic adenoma: a case report

the cutting surface was gray and white. Pa- thology observation: dominant epithelial com- ponents intermingled with chondroid, myxoid and fibrous stroma. The structure was pleomor- phic showing the glandular epithelium and myo- epithelial epithelium. Two kinds of epithelium formed a double tubular structure, myoepithe- lial cells distributed in the myxoid regions. The tumor infiltrated local capsule. Histological diagnosis: pleomorphic tumor (Figure 2). Figure 1. Enhanced CT scan of the parotid gland. A. Two high density lesions were seen in the left parotid gland. Mild Homogeneous enhancement was seen in both tumors. B. The posterior one was 22 mm in diameter. C. The anterior one was 15 mm in diameter.
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Superselective angio CT of brain tumors

Superselective angio CT of brain tumors

All tumors were proved histologically by biopsy or sur- gery. Four astrocytomas were grade II, 10 were grade III, and 5 were grade IV. Superselective angio-CT was per- formed before superselective infusion of ACNU. The pa- tients underwent transfemoral catheterization with a 6F catheter (PU; Toray, Tokyo, Japan). The catheter was placed in either the cervical internal carotid artery or the cervical segment of a vertebral artery. After intraarterial digital subtraction angiography with the PU catheter, a Tracker-18 catheter (Target Therapeutics, Los Angeles, Calif) was passed coaxially inside the PU catheter and advanced into the feeding arteries of the tumor. Hepa- rinized saline was administered through the PU and Track- er-18 catheters. Once the Tracker catheter was in the proper position, digital subtraction angiography was per- formed with a hand injection of diluted contrast material. Patients were then moved to the CT suite.
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MESENCHYMAL ORIGIN TUMORS OF PAROTID GLAND

MESENCHYMAL ORIGIN TUMORS OF PAROTID GLAND

a large size; it generally appears as a mass characterized by being: painless, ill-defined, firm, non-inflammatory, deeply located, fixed to the underlying structures, and which grow slowly. [2,4,6] The natural biological behavior of deep fibromatosis can be unpredictable and variable. [10] that means that a significant proportion (about 50%) of patients have tumors that remain spontaneously stable after initial progression or even regress and hence benefit from a front line non- aggressive policy (watch and wait) (10) . This spontaneous regression has been observed in the menarche and menopause [5]
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Parotid pleomorphic adenomas: delayed CT enhancement

Parotid pleomorphic adenomas: delayed CT enhancement

Our results regarding the average size, margin ap- pearance, and location within the parotid gland typi- cal of parotid pleomorphic adenomas are concordant with those of the literature. Our finding of delayed pleomorphic adenoma enhancement, however, with an increasingly homogeneous filling in of contrast material, has not, to our knowledge, been emphasized previously. This observation may explain some of the differing descriptions of the CT enhancement pattern of parotid pleomorphic adenomas discussed above. As shown in Figure 1, parotid CT performed too early after IV administration of contrast material could result in markedly decreased lesion conspicuity. The fact that the other parotid masses we examined over- whelmingly showed early intense contrast enhance- ment may potentially be of value in formulating the differential diagnosis, although further work is re- quired to substantiate this hypothesis.
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