The oncofetal protein IMP3 is an indicator of early recurrence and poor outcome in mucoepidermoid carcinoma of salivary glands

Objective: Mucoepidermoid carcinoma(MEC) is the most common primary malignancy of the salivary glands. Insulin-like growth factor-II m RNA-binding protein-3(IMP3) is an important prognostic factor in some cancers and a tool that differentiates between benign and malignant pancreatic lesions. This study aimed to identify a relationship between the expression of IMP3 and the outcome of salivary gland MEC, as well as to differentiate MEC from pleomorphic adenoma(PA).Methods: Tissue specimens from 70 cases of salivary gland MEC, 40 cases of PA, and 10 cases with normal salivary gland were examined immunohistochemically for IMP3. The association among the expression of IMP3, clinicopathological characteristics and patient's survival was assessed.Results: IMP3 was present in 51.4% of MEC but absent in PA and normal salivary gland tissues. IMP3 expression was associated with age > 60 years, submandibular gland tumors, tumor size > 4 cm, high-grade tumors, lymph node metastasis, involvement of surgical margins, perineural invasion, distant metastasis, advanced TNM stage, tumor relapse, and death(P<0.05). Increased expression of IMP3, tumors of the submandibular gland, and lymph node metastasis were independent prognostic factors of disease-free survival(DFS). In addition, IMP3 was a strong predictor of overall survival(OS) together with distant metastasis and intermediate and high-grade tumors.Conclusions: IMP3 expression is highly important in evaluating the outcome of MEC. IMP3 can be used to differentiate MEC from PA of salivary glands.

Influence of the Radiation Dose to Salivary Glands on Xerostomia in Patients with Head and Neck Carcinomas

Purpose: Investigation of the influence of radiation dose to salivary glands on xerostomia in patients with head and neck cancers. Methods: From October 2002 to December 2011, 548 patients with head and neck carcinomas were treated in our department using intensity modulated radiotherapy (IMRT). 325 patients were eligible for analysis more than 1 year after irradiation. Xerostomia was evaluated according to the criteria of Radiation Therapy and Oncology Group (RTOG) and xerostomia related questionnaire. For statistical analysis grade 1 and 2 were recorded as mild and grade 3 and 4 as severe xerostomia. The dosimetric values for absolute mean dose, biological equivalent mean dose (EQD2), the relative organ volume not exceeding 20 Gy, 25 Gy and 30 Gy (V20, V25, V30) for all 4 major salivary glands or for both parotid glands only were used for analysis. V20 revealed the best discrimination between both patient groups (with vs. without xerostomia), compared to parameters V25 and V30. Therefore the volume of the salivary glands receiving less than 20 Gy (V 20Gy) was analyzed additionally. Mann-Whitney-U-test, Kruskal-Wallis-test and logistic regression were used in statistical analysis. Results: A TD 50 can be determined for the occurrence of xerostomia more than one year after radiotherapy for both parotid glands of 19.3 Gy for the mean dose absolute, 11.2 Gy for the mean dose EQD2, 38.2% for V20, 26.8% for V25, 18.7% for V30, 34.9 ml for V 20Gy. For all major salivary glands theses values were 25.7 Gy for the mean dose absolute, 15.6 Gy for the mean dose EQD2, 51.3% for V20, 41.1% for V25, 33.9% for V30 and 34.8 ml for V 20Gy. Conclusions: The identification of a tolerance dose for the salivary glands for treatment planning appears to be difficult, as the dose-response correlation only shows a flat slope. Additionally, a large interindividual variability seems to exist. We could not found any threshold dose for development of xerostomia.

Overall and cause-specific survival for mucoepidermoid carcinoma of the major salivary glands:Analysis of 2210 patients

BACKGROUND Mucoepidermoid carcinoma(MEC)is a rare malignancy of the head and neck;however,it accounts for a majority of the tumors of the salivary glands.This study used a national population-based registry to describe the pre-treatment and treatment-related prognostic factors that influence survival in patients with MEC of the major salivary glands.To our knowledge,this is the largest populationbased study examining predictors of both overall and cause-specific survival of MEC of the major salivary glands.AIM To identify prognostic factors influencing overall survival(OS)and cause-specific survival(CSS)of patients with MEC of the major salivary glands.METHODS We used the Surveillance,Epidemiology and End-Results Database of the National Cancer Institute to investigate a variety of factors that could influence survival of patients diagnosed with mucoepidermoid carcinoma of the major salivary glands.A total of 2210 patients diagnosed with MEC of the major salivary glands during the years of 1975-2016 were studied.The primary endpoints were OS and CSS.Cox regression analysis was used to perform univariate and multivariate analyses of clinical variables such as age at diagnosis,diagnosis year,sex,race,tumor size,stage,grade,treatment with or without surgical excision,and adjuvant radiotherapy treatment.RESULTS A total of 2210 patients diagnosed with MEC of the major salivary glands met inclusion criteria.In this study,95%of patients underwent surgical excision and 41%received adjuvant radiation therapy.Median OS time for Grade I,II,and III/IV was 401 mo(±48.25,95%CI),340 mo(±33.68,95%CI)and 55 mo(±11.05,95%CI),respectively.Univariate analysis revealed that lack of surgical excision was associated with decreased OS[hazard ratio(HR)4.26,P<0.0001]and that patients with localized disease had improved OS compared to both regional and distant disease(HR 3.07 and 6.96,respectively,P<0.0001).Additionally,univariate analysis demonstrated that male sex,age over 50 at diagnosis,Grade III tumors,and increasing tumor size were associated with worsened OS(P<0.0006).Univariate analysis of CSS similarly revealed that lack of surgical excision and Grade III carcinoma conferred decreased CSS(HR 4.37 and 5.44,respectively,P<0.0001).Multivariate analysis confirmed that increasing age,in 10-year age bands,advanced tumor stage,increasing tumor size,Grade III carcinoma,male sex,and lack of surgical excision were associated with a statistically significant decrease in OS and CSS(P<0.04).Of note,multivariate analysis revealed that the use of adjuvant radiation therapy was not associated with improved OS or CSS.CONCLUSION Multivariate analysis demonstrated increasing age,advanced tumor stage,increasing tumor size,Grade III carcinoma,male sex,and lack of surgical excision were associated with decreased OS and CSS(P<0.04).

Partial Characterization of Thrombin Inhibitor(s) Derived from Salivary Glands of the Tick, <i>Hyalomma dromedarii</i>, and Related Anti-Cancer Potential

A long-term blood feeder, like the Hyalomma dromedarii tick, requires extended control over all hemostatic defense mechanisms generated by the host during feeding, including blood coagulation. To overcome this, ticks have evolved numerous molecules that target proteases in the blood coagulation cascade. New insights into the role of clotting factors in the development and progression of cancer have identified anticoagulant treatment as a potential therapeutic approach. In this context, the present work assessed the anticoagulation activities of crude and fractionated salivary gland extract (SGE) prepared from semi-fed H. dromedarii females. Additionally, the antitumor effects of the potent anti-thrombin fractions were determined against colon cancer (Caco-2) and normal skin (HFB4) cells. Crude SGE significantly prolonged clotting time in prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) assays and inhibited thrombin in FII-activity assay. Using anion-exchange chromatography, the fractions that strongly inhibited thrombin (3.A4 and 3.A5) were eluted. Both fractions prolonged the aPTT and TT clotting times and reduced the activity of FII significantly. The protein profiles of both fractions indicated the presence of a single polypeptide band of about 99 kDa. Regarding anti-cancer potential of the tested fractions, Caco-2 cells showed reduced viability with obvious morphological changes, induced apoptosis and a reduced level of vascular endothelial growth factor (VEGF). G2/M cell cycle arrest was observed only in 3.A5-treated cells. No cytotoxic effects were observed in HFB4 cells. These results demonstrated the potential of tick-derived anticoagulants, specifically thrombin inhibitors, as effective tools in colorectal cancer treatment. Further purification of the effector molecule(s) is required to fully characterize their structures and mechanisms of action.

Evaluation of P53 in Salivary Glands Tumors among a Syrian Sample

Objective： to evaluate the expression of P53 in salivary glands tumors among a Syrian sample. Material and methods： a retrospective analysis of gross and light microscopic features 50 salivary glands tumors that were treated and diagnosed at Almoasat hospital, the main hospital in Damascus. Only benign salivary glands tumors were included in this study, mainly pleomorphic adenoma and warthin＇s tumor. Results： 158 cases were studied from 2009 to 2016. Pleomotphic adenoma was the most occurring tumor （47.7%）, followed by Warthin tumor （30.9%） and mucoepidermoid carcinoma （6.1%）. Lesions of in minor salivary glands compromised （11.03%）. Only pleomorphic adenoma and warthin＇s tumor were included in the practical part of the study. All specimens showed a total negativity for P53 when they were studied under the light microscope. Conclusion： the result of this study agreed with some previously studies in other countries and was not similar to others in other countries. No differences were observed as to the type of the tumor. These results could be related to racial factors.

Salivary Glands Tumors： A Clinicopathological Study about the Incidence and Distribution of Salivary Glands Tumors among a Syrian Population Amirah Alnour

Objective： to investigate the clinicopathologic characters of salivary glands tumors in Damascus, Syria. Material and methods： a retrospective study on salivary glands tumors diagnosed at Almoasat hospital, the main hospital in Damascus, from 2009 to 2016. We measured the data related to patient age, gender, tumor site and the histopathologic diagnosis. Results： out of 158 cases over eight years, 62.2% was benign tumors, 9.4% was malignant tumors and 28.4% was inflammatory lesions. Pleomotphic adenoma was the most occurring tumor （47.7%）, followed by Warthin tumor （30.9%） and mucoepidermoid carcinoma （6.1%）. Lesions in minor salivary glands compromised （11.03%）. The peak ages of incidence were the third and fourth decades （38.35%）. A slight predilection for females was observed. Conclusion： the results of this study are similar to the previous studies in other countries. However differences were observed as to the frequencies of histopathologic types. These differences could be attributed to racial factor and the latest five years of war in Syria.

Autoimmune pancreatitis with IgG4-positive plasma cell infiltration in salivary glands and biliary tract

A 62-year-old male was referred to our hospital because of liver dysfunction, diffuse pancreatic swelling, and trachelophyma. At admission, the patient was free of pain. Physical examination showed enlarged and palpable bilateral submandibular masses, but no palpable mass or organomegaly in the abdomen. Laboratory findings were as follows： total protein 90 g/L with γ-globulin of 37.3% （33 g/L）, total bilirubin 4 mg/L, aspartate aminotransferase 39 IU/L, alanine aminotransferase 67 IU/L,γ-glutamyl transpeptidase 1 647 IU/L, and amylase 135 IU/L. Autoantibodies were negative, and tumor markers were within the normal range. Serum IgG4 level was markedly elevated （18 900 rag/L）. Computed tomography （CT） showed diffuse swelling of the pancreas and dilatation of both common and intra-hepatic bile ducts. Endoscopic retrograde pancreatography （ERP） revealed diffuse irregular and narrow main pancreatic duct and stenosis of the lower common bile duct. Biopsy specimens from the pancreas, salivary gland and liver showed marked periductal IgG4-positive plasma cell infiltration with fibrosis. We considered this patient to be autoimmune pancreatitis （AIP） with fibrosclerosis of the salivary gland and biliary tract, prescribed prednisolone at an initial dose of 40 mg/d. Three months later, the laboratory data improved almost to normal. Abdominal CT reflected prominent improvement in the pancreatic lesion. Swelling of the salivary gland also improved. At present, the patient is on 10 mg/d of prednisolone without recurrence of the pancreatitis. We present here a case of AIP with fibrosclerosis of salivary gland and biliary tract.

30-bp DELETION IN LATENT MEMBRANE PROTEIN 1 (LMP-1) ONCOGENE IN LYMPHOEPITHELIAL CARCINOMA OF SALIVARY GLANDS

Objective: To investigate the 30 bp deletion in LMP-1 in lymphoepithelial carcinoma of salivary glands, and to clarify the deletion rate. Methods: 46 cases of LEC were subjected to PCR examination for the 3?terminal region of LMP-1 gene, in order to observe the 30 bp deletion. To reduce the influence of unsuccessful DNA extraction from paraffin-embedded tissue sections, a bactin PCR was performed at the same time. Additionally, DNA sequencing was performed on 1 case without deletion and 1 case with deletion. Results: 4 of 46 specimens were proved to contain no suitable DNA sample by bactin gene amplification. In the remaining 42 cases, LMP-1 DNA was detected in 35/42 (83.3%) LEC cases. Two kinds of PCR products were found in these 35 cases after further DNA sequencing. 31 cases (88.6%) carried 316 bp product and 4 cases (11.4%) carried 286 bp product. Conclusion: Some LECs of salivary glands carry del-LMP-1. In our study, the deletion rate was 11.4% (4/35).

DETECTION OF HUMAN HERPESVIRUS 6(HHV-6) DNA IN SALIVARY GLANDS BY THE POLYMERASE CHAIN REACTION

To assess the presence of HHV-6-Specific DNA in human salivary glands, eighteen specimens of salivary gland tissue were investigated using the polymerase chain reaction. Eight of nine parotid glands, five of seven submandibular glands and one of two sublingual glands were found to have amplification of the HHV-6-specific sequence. The findings suggest that salivary gland tissue is one of the potential sites for HHV-6 persistence following primary infection and that saliva is a vehicle for transmission of the virus.

Myoepithelial carcinoma of the salivary glands: behavior and management

To investigate the biological behavior and proper management of myoepithelial carcinomas of salivary glands Methods Twenty seven cases of myoepithelial carcinoma of salivary glands were retrospectively studied and their detailed clinical and follow up data were presented Results The subjects consisted of 17 men and 10 women aged 16 to 73 years (mean age: 51 years) The parotid gland was the most common site (n=14) of cancer Clinical features included extensive local growth, invasion of the surrounding tissues, infrequent cervical lymph node metastasis but high rates of distant metastasis, frequent/multiple recurrences and poor prognosis Conclusions Myoepithelial carcinomas of the salivary gland should be classified as high grade malignancies Early and radical surgery with close follow up are essential for achieving favorable outcomes Radiotherapy appears to be non sensitive and elective neck dissection is generally unnecessary

Pattern and Trends in the Presentation of Salivary Gland Tumours in a Tertiary Centre in Gombe, Northeast Nigeria

Background: Salivary gland tumours (SGTs) are rare, but recent reports suggest an increasing incidence. Although there are previous Nigerian studies on the patterns of SGTs, patterns and trends of disease may change over time. The aim of this study was to describe the pattern of presentation of SGTs, and to determine the trends in occurrence of SGTs at Federal Teaching Hospital (FTH), Gombe over a period of 15 years. Method: This descriptive study included cases of histologically diagnosed SGTs from January 2008 to December 2022. Relevant information (age, gender, site, year of diagnosis, and histopathologic diagnosis) was extracted from the cancer registers and histopathologic records. The lesions were then categorized into benign and malignant SGTs and grouped into three groups spanning 5 years each based on the year of diagnosis. Data analysis was done using IBM SPSS version 23, and p ≤ 0.05 was considered statistically significant. Results: There were 93 (61.2%) benign and 59 (38.8%) malignant SGTs. Benign SGTs had a mean age of 36.4 ± 13.6 years, and were more common in females (57.0%), and in the parotid (41.9%). Pleomorphic adenoma (94.6%) was the most common benign SGT. Malignant SGTs had a mean age of 44.5 ± 18.4 years, with male predilection (54.2%) and occurrence mostly in the palate (27.6%) and parotid (22.4%). Mucoepidermoid carcinoma (39.0%) and adenoid cystic carcinoma (32.2%) were the most frequent malignant SGTs. The mean age of occurrence of malignant SGTs was significantly higher than that of benign SGTs (p = 0.005). The trend analysis showed that there has been a steady rise in the proportion of males presenting with malignant SGTs. Similarly, there has been a steady increase in the frequency of benign SGTs in the parotid. The palate was the predominant site for the malignant SGTs between 2008 and 2012, but in the last five years (2018 to 2022), the parotid has become the predominant site. Over the duration of the study, the ratio of benign to malignant SGTs has remained relatively constant. Conclusion: While the overall pattern of presentation of SGTs in Gombe is similar to reports in the literature, this study has identified some changes in trends over the years.

Pleomorphic adenoma(mixed tumor)of the upper lip:A case report

BACKGROUND Salivary gland tumors are relatively rare.Most minor salivary gland tumors are malignant with benign tumors accounting for 18%of the tumors.Pleomorphic adenoma(PA)is the most common salivary gland tumor.Lip PA is uncommon with 9.8%occurring in the upper lip.We are adding on the knowledge of the rare upper lip PA(benign mixed tumor).CASE SUMMARY We report an upper lip PA(benign mixed tumor)in a 28-year-old man.His complaint was a painless swelling on the upper lip.A painless,non-tender,well-circumscribed,slightly mobile,sessile,nodular,and rubbery(in consistency)tumor measuring 5.0 cm x 2.0 cm was noted on the left side of his upper lip.The overlying skin was not fixed and of normal color.There was no ulceration,and palpation did not elicit pain or bleeding.There was no history of trauma.Blunt dissection was used to completely excise the nodular,whitish,and encapsulated tumor.Microscopy showed a well-circumscribed and partly encapsulated biphasic lesion,with large lobules of myxo-chondroid stroma and intervening cellular nodules of basaloid cells,well-formed tubules containing eosinic secretion,and nests of myoepithelial cells.A diagnosis of PA(benign mixed tumor)was confirmed.CONCLUSION Blunt dissection is indicated to preserve the cosmesis and function of the upper lip.

Evaluation of Quality of Life Related to I-131 Therapy in Patients with Well-Differentiated Thyroid Cancer and Emphasis in Salivary Morbidity: A Follow up Study after Treatment

Goal: To evaluate the impact of iodine-131 therapy received during childhood and adolescence and correlate it with the quality of life in these patients. Methods: We studied 19 patients diagnosed with cancer in childhood or adolescence who underwent thyroidectomy and supplemental therapy with I-131. We also recruited a control group of healthy subjects with the same demographic parameters. All patients were subjected to a scintigraphy examination of the salivary glands, and were also asked to complete a questionnaire in order to assess their overall quality of life. In addition, a more specific questionnaire for patients with head and neck cancer was also given to all study participants. Results: The quantitative and qualitative analyses of the salivary glands showed functional deficits with greater involvement of the parotid gland for volume, concentration and excretion. The right submandibular gland showed significant changes for volume in the patient group. The questionnaires made it possible to observe significant differences between the patient and control groups for symptoms such as thick saliva, dry mouth and speech problems. Conclusion: In spite of being very effective and widely used, iodine radionuclide therapy is correlated with a lower quality of life in young people.

Pleomorphic Adenoma of the Hard and Soft Palate: A Case Presentation and Literature Review of Minor Salivary Gland Neoplasms

Introduction: Minor salivary gland tumors are relatively rare, but have a higher chance of malignancy than major salivary gland tumors. The palate appears to be the most commonly involved site. The most frequent benign tumor is the pleomorphic adenoma. Case report: We report a case of a pleomorphic adenoma, which occurred in the hard and soft palate of a 34-year-old female and presented as an asymptomatic slow growing, painless mass. The patient was successfully treated with surgical excision. Discussion: Minor salivary gland tumors should be considered in the differential diagnosis of oral cavity and especially palate tumors. A histological examination is necessary due to the high percentage of malignancy.

The effect of basic fibroblast growth factor on regeneration in a surgical wound model of rat submandibular glands

This study developed an animal model of surgically wounded submandibular glands （SMGs） and investigated the effects of collagen gel with basic fibroblast growth factor （bFGF） on tissue regeneration of surgically wounded SMGs in vivo. The animal model was produced by creating a surgical wound using a 3-mm diameter biopsy punch in SMGs. The wound was filled with collagen gel with bFGF （bFGF group） or without bFGF （control group）. In the animal model of surgically wounded SMGs, salivary glands without scar tissue around the wound area were observed with smaller areas of collagen gel. Small round and spindle-shape cells invaded the collagen gel in both groups after operation day （AOD） 5, and this invasion dramatically increased at AOD 7. Host tissue completely replaced the collagen gel at AOD 21. The invading immune cells in the group treated with collagen gel with bFGF were positive for vimentin, g-smooth muscle actin （αSMA）, CD49f, c-kit and AQP5 at AOD 7. Similarly, the mRNA expression of vimentin, αSMA, CD49f, keratin 19 and AQP5 was also increased. This study suggests that the use of collagen gels with bFGF improves salivary gland regeneration.

Localization and potential function of androgen receptor in rat salivary gland

Aim： To investigate the localization and quantity of androgen receptor （AR） in the salivary glands of rats with further analysis on the effect of castration. Methods： Sixty male Wistar rats, aged 30-60 days, were randomly divided into three groups （castrated, sham-operated and normal controls） with 20 rats in each group. The rats in the castrated group were castrated and the submaxillary glands were removed after 1 week. The salivary glands of the rats in the sham-operated and the normal control groups were also removed. Parts of the salivary glands were fixed for immuohistochemistry and in situ hybridization assays. Other parts were used for Western blot. Results： AR immunoreactivity in the three groups was localized in the glandular epithelial cells of the serous acinus and the glandular duct of the salivary gland, mainly in the nuclei. AR mRNA hybridization signals in the salivary glands of the castrated group were mainly distributed in the epithelial cells of the convoluted and secretary ducts; AR mRNA in the sham-operated and the normal control groups were found in the epithelial cells of the convoluted, the secretary and the excretory ducts. The quantity of AR in the salivary glands was decreased significantly in the castrated rats compared with the sham-operated and the normal controls. Moreover, epidermal growth factor （EGF） secreted by the salivary glands was also decreased in the castrated rats. Conclusion： Castration appears to affect the production of AR in the salivary gland and the distribution of the AR mRNA and could further affect the function of the salivary gland. The changes of AR and the distribution of AR mRNA may play an important role in the interactions between the testes and the salivary gland. （Asian J Androl 2005 Sep; 7： 295-301）

Expressions of chemokine receptor CXCR4 and its ligand CXCL12 in salivary adenoid cystic carcinoma

Objective: To examine expressions of chemokine receptor CXCR4 and its ligand CXCL12 in primary focus and lymphogenous metastasis of salivary adenoid cystic carcinoma (ACC) with lung metastasis. Methods: Using immunohistochemical hypersensitivity catalyzed signal amplification (CSA), expressions of chemokine receptor CXCR4 and ligand CXCL12 were detected in tissue specimens from 20 cases of primary cancer focus and lymphogenous metastasis of salivary adenoid cystic carcinoma, of which 7 cases were associated with lung metastasis and 3 with lympogenous metastasis. Twenty cases of tongue carcinoma (including 10 cases with lymphogenous metastasis) and 15 cases of mucoepidermoid carcinoma (including 5 cases with lymphogenous metastasis) were used as the malignant control group;and salivary mixed tumor (n=10), tongue leukoceratosis (n=10) and cervical lymph node reactive hyperplasia (n=10) were used as the benign control group. Results: Expression of CXCR4 in the tissues and lymph metastases of oral and maxillofacial salivary ACC, mucoepidermoid carcinoma and tongue carcinoma was significantly higher than that of the benign control group (P<0.05); expression of CXCR4 in the primary focus of ACC was significantly higher than that of the malignant control group; and expression of CXCR4 in the ACC with lung metastasis was 87.1% (6/7), significantly higher than that without lung metastasis(P<0.01). There was evident positive expression of CXCL12 in endotheliocytes of microvessels within cancer and paracancer tissues and significantly high expression of CXCL12 in lymphogenous metastasis(P<0.05). Conclusion: Chemokine receptor CXCR4 and its ligand CXCL12 may be associated with local invasion and lymphogenous metastasis of oral and maxillofacial cancer, especially with lung metastasis of salivary ACC.

Advanced magnetic resonance imaging findings in salivary gland tumors

Salivary gland tumors(SGTs)make up a small portion(approximately 5%)of all head and neck tumors.Most of them are located in the parotid glands,while they are less frequently located in the submandibular glands,minor salivary glands or sublingual gland.The incidence of malignant or benign tumors(BTs)in the salivary glands varies according to the salivary gland from which they originate.While most of those detected in the parotid gland tend to be benign,the incidence of malignancy increases in other glands.The use of magnetic resonance imaging(MRI)in the diagnosis of SGTs is increasing every day.While conventional sequences provide sufficient data on the presence,localization,extent and number of the tumor,they are insufficient for tumor specification.With the widespread use of advanced techniques such as diffusion-weighted imaging,semiquantitative and quantitative perfusion MRI,studies and data have been published on the differentiation of malignant or BTs and the specificity of their subtypes.With diffusion MRI,differentiation can be made by utilizing the cellularity and microstructural properties of tumors.For example,SGTs such as high cellular Warthin’s tumor(WT)or lymphoma on diffusion MRI have been reported to have significantly lower apparent diffusion values than other tumors.Contrast agent uptake and wash-out levels of tumors can be detected with semiquantitative perfusion MRI.For example,it is reported that almost all of the pleomorphic adenomas show an increasing enhancement time intensity curve and do not wash-out.On quantitative perfusion MRI studies using perfusion parameters such as Ktrans,Kep,and Ve,it is reported that WTs can show higher Kep and lower Ve values than other tumors.In this study,the contribution of advanced MRI to the diagnosis and differential diagnosis of SGTs will be reviewed.

Salivary Gland Branching Morphogenesis——Recent Progress and Future Opportunities

Salivary glands provide saliva to maintain oral health, and a loss of salivary gland function substantially decreases quality-of-life. Understanding the biological mechanisms that generate salivary glands during embryonic development may identify novel ways to regenerate function or design artificial salivary glands. This review article summarizes current research on the process of branchingmorphogenesis of salivary glands, which creates gland structure during development. We highlight exciting new advances and opportunities in studies of cell-cell interactions, mechanical forces, growth factors, and gene expression patterns to improve our understanding of this important process.

Prospect of Functional Salivary Gland Enhancement with Biomedical Strategies for Head and Neck Cancers

Xerostomia is the main complication inflicting head and neck cancer patients treated with radiotherapy.Conventional treatment is not very effective in alleviating this morbidity.Biomedical strategies such as gene transfer and tissue engineering have made substantial progress that will potentially lead to successful new treatment options for this condition.This report reviews the process of radiation damage to the salivary glands and the advances in functional salivary gland enhancement with these two brand-new technologies.