Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Tumors of the Salivary Gland

Parotid Gland Segmentation Using Purely Transformer-Based U-Shaped Network and Multimodal MRI

Parotid gland tumors account for approximately 2% to 10% of head and neck tumors. Segmentation of parotid glands and tumors on magnetic resonance images is essential in accurately diagnosing and selecting appropriate surgical plans. However, segmentation of parotid glands is particularly challenging due to their variable shape and low contrast with surrounding structures. Recently, deep learning has developed rapidly, and Transformer-based networks have performed well on many computer vision tasks. However, Transformer-based networks have yet to be well used in parotid gland segmentation tasks. We collected a multi-center multimodal parotid gland MRI dataset and implemented parotid gland segmentation using a purely Transformer-based U-shaped segmentation network. We used both absolute and relative positional encoding to improve parotid gland segmentation and achieved multimodal information fusion without increasing the network computation. In addition, our novel training approach reduces the clinician's labeling workload by nearly half. Our method achieved good segmentation of both parotid glands and tumors. On the test set, our model achieved a Dice-Similarity Coefficient of 86.99%, Pixel Accuracy of 99.19%, Mean Intersection over Union of 81.79%, and Hausdorff Distance of 3.87. The purely Transformer-based U-shaped segmentation network we used outperforms other convolutional neural networks. In addition, our method can effectively fuse the information from multi-center multimodal MRI dataset, thus improving the parotid gland segmentation.

Mucin-rich salivary gland tumors

Salivary gland neoplasms characterized by abundant mucin production are rare but have long been recognized. Due to their scarcity, precise classification has long eluded these mucin-rich tumors. Recent molecular discoveries, however, have shed considerable light on the genetic underpinnings of mucin-rich salivary gland neoplasms. This manuscript will review the most up-to-date information on this fascinating group of salivary gland neoplasms.

Appraisal of clinical practice guidelines for salivary gland cancer management utilizing AGREE II instrument

OBJECTIVE

Salivary gland cancers (SGC) are rare neoplasms which comprise 1-5 % of all head and neck cancers. SGCs can be managed by resection, radiosurgery, chemotherapy, or a combination of these. Our team appraised the quality of clinical practice guidelines (CPGs) for SGC treatment and management using the Appraisal of Guidelines for Research and Evaluation (AGREE-II) instrument.

DATA SOURCES

PubMed, Scopus, & EMBASE were reviewed for CPGs regarding SGC management from database inception to January 1st, 2023.

REVIEW METHODS

The AGREE-II instrument was used by 4 reviewers to independently evaluate guidelines. Domain scores were generated with a satisfactory threshold being >60 % - a "high" quality CPG required >4 satisfactory domains. Intraclass correlation coefficients (ICCs) were used, via R 4.2.1., to determine inter-reviewer variability.

RESULTS

Literature review identified 645 articles, with six being included after applying inclusion and exclusion criteria. Of the six included articles, one CPG was "high" quality and 5 were "low" quality. The domains with the highest scores were "Editorial Independence" (72.57 ± 36.60) and "Clarity and Presentation" (63.19 ± 26.08), while the lowest were "Rigor of Development" (34.03 ± 30.63) and "Applicability" (30.21 ± 30.46). ICC scores for each domain ranged from 0.937 to 0.983, indicating a high level of inter-rater agreement.

CONCLUSION

This study found that most CPGs for the treatment and management of SGC were of "low" quality, with only one guideline being considered "high" quality based on the standard set by the AGREE-II instrument. These findings indicate that there is a high level of variability and little standardization when it comes to the quality of CPGs.

Patterns and Trends in Adjuvant Therapy for Major Salivary Gland Cancer

OBJECTIVE

To investigate adjuvant therapy indications, utilization, and associated survival disparities in major salivary gland cancer (MSGC).

STUDY DESIGN

Retrospective cohort study.

SETTING

The 2006 to 2017 National Cancer Database.

METHODS

Patients with surgically resected MSGC were included (N = 11,398). pT3-4 classification, pN2-3 classification, lymphovascular invasion, pathologic extranodal extension (pENE), and positive surgical margin (PSM) were considered indications for adjuvant radiotherapy (aRT). pENE and PSM were considered possible indications for adjuvant chemotherapy. Multivariable logistic and Cox regression models were implemented.

RESULTS

Among 6694 patients with≥ $\ge $ 1 indication for aRT, 1906 (28.5%) received no further treatment and missed aRT. Age, race, comorbidity status, facility type, and distance to reporting facility were associated with missed aRT (P < .025). Among 4003 patients with ≥1 possible indication for adjuvant chemoradiotherapy (aCRT), 914 (22.8%) received aCRT. Patients with pENE only (38.5%) and both pENE and PSM (44.0%) received aCRT more frequently than those with PSM only (17.0%) (P < .001). Academic facility was associated with aCRT utilization (P < .05). aCRT utilization increased between 2006 and 2017 in both academic (14.8% vs 23.9%) and nonacademic (8.8% vs 13.5%) facilities (P < .05). Among 2691 patients with ≥1 indication for aRT alone, missed aRT portended poorer OS (hazard ratio [HR]: 1.61, 95% confidence interval [CI]: 1.28-2.03, P < .001). Among 4003 patients with ≥1 possible indication for aCRT, aRT alone (HR: 1.02, 95% CI: 0.89-1.18, P = .780) and aCRT were associated with similar OS.

CONCLUSION

Missed aRT in MSGC occurs frequently and portends poorer OS. Further studies clarifying indications for aCRT are required.

Current landscape and future trends in salivary gland oncology research-a bibliometric evaluation

Background

The salivary glands are susceptible to both endogenous and exogenous influences, potentially resulting in the development of oncology. With the wide application of various technologies, research in this area has experienced rapid growth. Therefore, researchers must identify and characterize the current research hot topics to grasp the forefront of developments in the dynamic field of salivary gland oncology. The objective of this study was to thoroughly assess the current status and identify potential future research directions in salivary gland oncology.

Methods

The relevant salivary gland oncology dataset was obtained from the Web of Science Core Collection (WOSCC) database. Subsequently, VoSviewer and CiteSpace were employed for further evaluation.

Results

A total of 9,695 manuscripts were extracted and downloaded from the WOSCC database. Our findings revealed a substantial surge in research volume over the past 12 years. The researchers' analysis revealed that Abbas Agami showed unparalleled dedication, with over 180 publications, and that RH Spiro had the highest cocitation count, confirming its status as a key figure in the field. The detection of bursts in secretory carcinoma and the integration of artificial intelligence in salivary oncology have attracted increasing interest. Notably, there is a discernible trend towards increased research engagement in the study of salivary gland malignancies.

Conclusions

This study not only evaluated the current research landscape in salivary gland oncology but also anticipates future trends. These insights could contribute to the advancement of knowledge and policymaking in salivary gland oncology.

Current Developments in Diagnosis of Salivary Gland Tumors: From Structure to Artificial Intelligence

Salivary glands tumors are uncommon neoplasms with variable incidence, heterogenous histologies and unpredictable biological behaviour. Most tumors are located in the parotid gland. Benign salivary tumors represent 54-79% of cases and pleomorphic adenoma is frequently diagnosed in this group. Salivary glands malignant tumors that are more commonly diagnosed are adenoid cystic carcinomas and mucoepidermoid carcinomas. Because of their diversity and overlapping features, these tumors require complex methods of evaluation. Diagnostic procedures include imaging techniques combined with clinical examination, fine needle aspiration and histopathological investigation of the excised specimens. This narrative review describes the advances in the diagnosis methods of these unusual tumors-from histomorphology to artificial intelligence algorithms.

Head and neck mucoepidermoid carcinoma: does AFIP histological grading correlate with rate of nodal metastases?

OBJECTIVE

The aim of this study is to retrospectively evaluate the presentation of head and neck mucoepidermoid carcinoma at the Royal Melbourne Hospital and identify the significance of AFIP histological grading on the risk of neck metastasis and cancer free survival.

MATERIALS AND METHODS

This study is a retrospective cohort analysis of patients treated for head and neck mucoepidermoid carcinoma at the RMH between 2005 and 2022. Patient demographics, treatment, pathology, in particular the AFIP histological grading of the primary tumour, and outcomes were collected and tabulated. Time to recurrence was recorded, and survival outcomes were calculated with Kaplan-Meier method. Comparisons were made on different histological grading and regional metastases.

RESULTS

Thirty-three patients were identified and thirty met the inclusion criteria. There was an age range of 18-77 years (median 54 years) with no significant sex difference. Our patients had a 94% 5-year survival and an 86% 10-year survival. Thirteen patients had elective neck dissection and 2 out of 13 (15%) of the patients had positive neck disease. Of the two patients with regional metastasis, the primary tumour was graded as intermediate and low grade. No high-grade MEC patients had regional metastasis.

CONCLUSION

Mucoepidermoid carcinoma of the head and neck is associated with a good disease-specific and overall survival despite the presence of regional metastasis. The AFIP histological grading system did not have a statistically significant correlation to the incidence of nodal metastasis.

Salivary gland tumors: an audit from a tertiary care centre in Northern India

Salivary gland tumors are relatively rare and can exhibit various clinical behaviors. The study aims to understand the natural history, pathology, diagnostic workup, and treatment strategies for these tumors to improve patient outcomes. The audit included patients with salivary gland tumors detected through radiology or cytology. Patients underwent surgery, with some receiving adjuvant treatment. Demographic information, treatment interventions, and survival outcomes were analyzed using SPSS software. A total 89 as malignant salivart gland tumours were audited Malignant tumors were predominantly found in the parotid gland, with fewer cases in the minor salivary gland and submandibular gland.The median age of presentation was 47 years, and the majority of patients were male. The study examined various pathological and clinical factors, including tumor stage, nodal status, and the presence of facial palsy. Surgical procedures and histological types of tumors were documented. Adverse histological features like positive margins, lymph node positivity, lympho-vascular invasion, extracapsular spread, and perineural invasion were noted. POSTOP RT was administered to high-risk patients. Most malignant salivary gland tumors were found in the parotid gland, while minor salivary gland tumors were underrepresented in the audit. Surgical practices were diverse. Radiotherapy protocols were relatively standardized. The study found that certain histological features, such as lymph node positivity, margin positivity, lympho-vascular invasion, perineural invasion, and extracapsular spread, were associated with adverse effects on DFS and OS. The findings suggest that specific histological features, including LVI and ECE have emerged as independent prognostic factors for DFS and OS.

Unusual Presentation of Adenoid Cystic Carcinoma of the Tongue: A Case Report and Review of the Literature

Adenoid cystic carcinoma (ACC) is a rare malignant tumor that affects the salivary glands. Its notable characteristics include aggressive local growth, infiltration of nerves (perineural invasion), a propensity to disseminate to other parts of the body (metastasize), and a high likelihood of recurrence. Here, we present the case of a 71-year-old male patient who presented with swelling on the posterior left side of his tongue, which had been causing him difficulty in chewing for the past six months. The parotid gland is frequently impacted in the head and neck area, with the tongue being comparatively uncommon. While distant metastasis is frequent, metastasis to nearby lymph nodes is not as common. However, if it does occur, it is associated with a poor prognosis and reduces the average survival age of the patient. The preferred treatment for ACC is surgical removal with wide resected margins. If it metastasizes to lymph nodes, then adjunct therapy is the treatment modality for the lesion. ACC exhibits three histopathological patterns: solid, tubular, and cribriform. The solid type is associated with a poorer prognosis compared to cribriform type, which typically has a better prognosis. This case, occurring on the tongue, is rare.

Oncocytic Lesions of Salivary Glands: Morphological, Immunohistochemical, and Molecular Findings

The fifth edition of the World Health Organization (WHO) classification introduces new diagnostic methods based on genetic alterations, providing insight into the molecular basis of lesions. As a result, the classification system has evolved, new entities have been introduced, and existing entities have been reclassified. Oncocytic lesions of salivary glands are a group of neoplastic conditions characterized by the presence of oncocytic cells. These lesions present a diagnostic challenge due to their overlapping histological features. Therefore, a comprehensive evaluation, including morphological, immunohistochemical, and molecular analysis, is crucial for accurate diagnosis and appropriate management. Accurate classification of salivary gland pathologies is essential for selecting the appropriate treatment methods and predicting outcomes. The introduction of new therapeutic approaches, such as targeted therapies for malignant salivary gland tumors, has improved patient outcomes. However, to effectively implement these therapies in clinical practice, a clear classification of lesions is necessary.

Molecular Factors in Carcinoma Ex Pleomorphic Adenoma: Systematic Review and Meta-Analysis

OBJECTIVE

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor. Although multiple reviews have been published on salivary gland malignancies, it has been a decade since the last dedicated systematic review pertaining to CXPA alone was published. This study examines molecular factors in CXPA diagnosis.

DATA SOURCES

MEDLINE, CINAHL, Embase, Scopus, Web of Science (BIOSIS), Cochrane CENTRAL, Health Collection (Informit), OpenDOAR, and GreyNet International.

REVIEW METHODS

Systematic review and meta-analysis from inception to October 31, 2022 for all English language studies pertaining to "carcinoma ex pleomorphic adenoma." Predicted incidence of each biomarker was calculated with meta-analysis. Comparison against pleomorphic adenoma (PA) and salivary duct carcinoma (SDC) when reported within the same study are performed. Risk of bias performed with JBI tool for prevalence studies.

RESULTS

Of 19151 unique studies undergoing abstract screening, 55 studies (n = 1322 patients) underwent data analysis. Biomarkers with >3 studies were p53, HER2, AR, EGFR, PLAG1, ERBB, ER, PR, HMGA2, p16, p63, a-SMA, RAS, PTEN, PDL1, BRAF, PIK3CA, and c-kit. Highest incidence was seen in AR, EGFR, p16, and p53. Significant differences were demonstrated compared with PA and SDC. There was high heterogeneity and overall high risk of bias within studies.

CONCLUSION

Molecular factors are an area of interest in the diagnosis of CXPA. Our study results support examining CXPA as a discrete cohort in future targeted therapy trials. Laryngoscope, 134:1042-1053, 2024.

Polymorphous Adenocarcinoma: A Systematic Review of the Literature and Presentation of Two Cases in a Less-Considered Anatomical Site

BACKGROUND

Polymorphous adenocarcinoma (PAC) is the second-most common malignant tumour of the minor salivary glands. Although PAC predominantly affects the palate, it can also involve the buccal mucosa. This systematic review aims to investigate the literature data about PAC. Furthermore, we report two cases of patients affected by PAC in an infrequently considered anatomical site.

METHODS

According to PRISMA guidelines, a systematic review search was conducted on PubMed, Scopus, and Web of Science. Observational studies conducted on patients with a histological diagnosis of PAC were selected and analysed. Furthermore, two cases of patients with PAC affecting the buccal mucosa were reported.

RESULTS

Twenty-nine studies were included, and 143 patients affected by PAC were analysed (62 males, 75 females, and 6 undefined, with a mean age of 57.4 ± 14.5 years). The palate was the most affected site (99/143, 69.2%), followed by the buccal mucosa (12/143, 8.4%). Moreover, we report two cases of patients with PAC affecting the buccal mucosa (one male and one female, with a mean age of 70.5 ± 2.5 years).

CONCLUSIONS

The present study underscores the importance of considering the buccal mucosa as a possible location of minor salivary gland tumours; although it is a less-considered affliction, it is not uncommon.

BubR1 and cyclin B1 immunoexpression in pleomorphic adenoma and polymorphous adenocarcinoma of minor salivary glands

The immunoexpression of BubR1 and cyclin B1 in pleomorphic adenoma (PA) and polymorphic adenocarcinoma (PAC) in minor salivary glands is poorly studied. Thus, a retrospective and observational study was performed to provide a better understanding of the role and immunopositivity patterns of these proteins in these lesions. Sixteen cases of PA and 16 cases of PAC were selected. Parenchyma cells were submitted to quantitative immunohistochemical analysis through the labeling index. Cytoplasmic immunoexpression of BubR1 was observed in neoplastic cells from all analyzed PA and PAC cases. All PA cases and 93.7% of PAC exhibited nuclear immunoexpression of BubR1. Higher cytoplasmic and nuclear immunoexpression of BubR1 was observed in PAC (p = 0.001 and p = 0.122, respectively). Cytoplasmic immunoexpression of cyclin B1 was observed in all cases of PA and PAC, with a higher labeling index in the latter (p < 0.001). There was a significant positive correlation between nuclear and cytoplasmic BubR1 immunoexpressions (p < 0.001) in PA and a significant negative correlation between BubR1 and cyclin B1 cytoplasmic immunoexpressions (p = 0.014) in PAC. The higher cytoplasmic and nuclear immunoexpression of BubR1 in PACs suggests the continuous maintenance of neoplastic cells in the cell cycle and migration. Higher immunoexpression of cyclin B1 supports this lesion's enhanced proliferative and migration ability.

A Rare Case of Submandibular Gland Squamous Cell Carcinoma: Diagnostic Challenges and Surgical Management

Squamous cell carcinoma (SCC) in salivary glands is rare, often posing diagnostic challenges. This case report presents a 75-year-old male with progressively increasing swelling and pain in the right submandibular gland, eventually diagnosed as moderately differentiated SCC. The diagnostic journey involved fine needle aspiration cytology, imaging studies, and histopathological examination. The patient underwent surgical intervention, including submandibular gland excision and selective neck dissection, which successfully achieved local control. Subsequent postoperative follow-up indicated a favorable outcome, with no significant complaints. This report contributes insights into the multidisciplinary diagnostic approach and underscores the importance of imaging modalities in managing salivary gland SCC. This rare case emphasizes the need for ongoing research to refine management strategies for salivary gland SCC. By presenting a comprehensive diagnostic and therapeutic approach, this report contributes to the limited literature on this malignancy, emphasizing its rarity and the necessity for continued exploration of long-term outcomes. In conclusion, our case provides valuable insights into the medical knowledge surrounding SCC in salivary glands, warranting attention and further investigation.

Malignant salivary gland tumors: agreement between fine needle aspiration biopsy, incisional biopsy and final histopathological diagnostic

BACKGROUND

Incisional biopsy is indicated for intraoral tumors, but it is a contraindicated surgical procedure for major salivary glands. To avoid complications and facilitate diagnosis, fine needle aspiration biopsy (FNAB) is a type of biopsy widely used for preoperative diagnosis in these glands.

MATERIAL AND METHODS

The aim of this study was to analyze the agreement between the diagnosis by FNAB (major glands), incisional biopsy (minor glands) and histopathological analysis of the surgical specimen in salivary gland tumors from a database (medical records) of patients treated in a cancer treatment reference center in the Northeast region of Brazil.

RESULTS

The sample consisted of 110 cases, being 86 of them malignant tumors in major salivary glands (parotid gland=73; submandibular gland=13) and 24 cases in minor salivary glands (palate). The female gender was the most affected (57.3%), especially in patients over 60 years (42.7%). In the TNM classification, 41.8% of the cases were in T2 at the time of diagnosis, with most of the regional lymph nodes in N0 (85.5%) and 87.3% of the cases in M0. FNAB was able to identify malignant neoplasms in 68.6% of the cases (n=59), while incisional biopsy in palatal tumors obtained agreement of 75% of the cases (n=18). The analysis revealed that tumors classified as T3-T4 (p=0.012) showed greater agreement between pre- and post-surgical diagnosis.

CONCLUSIONS

The results obtained in this study indicate that FNAB has similar accuracy to incisional biopsy in providing satisfactory preoperative diagnoses of malignant tumors in salivary glands.

PTEN Deregulation Mechanisms in Salivary Gland Carcinomas

Among the tumour suppressor genes that affect critically cell functions and homeostasis, phosphatase and tensin homolog deleted in chromosome 10 (PTEN- gene locus: 10q21) regulates the PI3K/Akt/mTOR signalling pathway. PTEN is deleted, mutated or epigenetically hyper-methylated in a variety of human solid malignancies. Salivary gland carcinomas (SGCs) belong to the head and neck carcinomas (HNCs) super category of solid malignancies. Histo-pathologically, they demonstrate a significant diversity due to a variety of distinct and mixed subtypes. Genetically, they are characterized by a broad spectrum of gene and chromosomal imbalances. Referring specifically to suppressor genes, PTEN deregulation plays a critical role in signaling transduction in the corresponding SGC pre- and malignant epithelia modifying the response rates to potential targeted therapeutic strategies. In the current review, we explored the role of PTEN deregulation mechanisms that are involved in the onset and progression of SGCs.

Clinicopathological analysis of 18 cases of secretory carcinoma of the salivary glands

Background/purpose

Secretory carcinoma (SC) is a rare salivary gland tumor that featured by ETV6::NTRK3 gene fusion, and was included in the WHO Classification of Head and Neck Tumors since 2017. Nevertheless, the description of SCs by WHO is still vague. This study examined 18 SC cases by using both histomorphology and molecular pathology for diagnostic determination, especially immunohistochemical features of SCs.

Materials and methods

Based on WHO characteristics, 18 patients with SC admitted between 2001 and 2022 were included in this study. Main histomorphological patterns, FISH analyses of the ETV6::NTRK3 gene fusion, and immunohistochemical analyses of S100, mammaglobin, DOG1, ADFP, CA6 and Ki-67 were performed.

Results

Among the 18 SC patients, the median age of onset was 39.22 years. Grossly, the average tumor size in 2.96 cm with various texture from soft to tough. The majority patients were positive for S100, mammaglobin, and negative for DOG1, except for one patient negative for S100 (Case 18). All patients were positive for ADFP, and the majority patients were negative for CA6, except for Case 9. Two cases were found recurrence, and the tumor were found both in parotid gland with local invasion.

Conclusion

Combined with the results of previous studies, we proposed that the combination of all five markers, S100, mammaglobin, DOG1, ADFP and CA6, could contribute more to differential diagnosis of SCs with other salivary carcinomas, especially with AciCC. The prognosis of SCs is optimistic in most cases, but larger patient cohort and long-term follow-up are still needed.

Secretory carcinoma of salivary glands with NTRK3 break-apart molecular rearrangement: Potential misdiagnosis with mucoepidermoid carcinoma

A woman presented a right submandibular gland lesion with cytologic diagnosis of mucoepidermoid carcinoma. Patient underwent sialoadenectomy en bloc with supraomohyoid neck dissection. Positivity for ETV6-NTRK3 genes fusion on surgical sample led to final diagnosis of secretory carcinoma (SC). Secretory carcinoma has been renamed by WHO in 2017 from mammary-analogue-secretory carcinoma (MASC). Only 649 have been reported until 2019. While cytologic alteration are shared with other neoplasms as the acinic cell and mucoepidermoid carcinomas, ETV6-NTRK3 rearrangement is pathognomonic of SC. Although usually indolent and with low-stage presentation, SC has higher rate of local recurrences and nodal involvement than ACC. Surgical treatment represent the gold standard. Real prevalence of SC is probably underestimated due to the recent WHO 2017 reclassification. While cytologic analysis does not allow to discriminate SC from other malignancies, chromosomal examination is recommended. When low-grade SC is diagnosed, complete surgical resection assures good prognosis.

Prognostic factors and treatment considerations of submandibular gland carcinomas: A population-based study

OBJECTIVES

The therapeutic regimen of submandibular gland carcinoma (SGC) has not reached consensus, especially for the neck treatment of patients with cN0.

MATERIALS AND METHODS

Patients with SGC were identified from the medical database of Shanghai Ninth People's Hospital. Kaplan-Meier analysis, univariate and multivariate Cox regression were employed to evaluate the survival and independent prognostic factors.

RESULTS

Two hundred and fifteen patients with SGC were retrospectively reviewed. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 71.5% and 77.8%, respectively. Multivariate analysis revealed that histological grade, cT classification, cN classification, and perineural invasion (PNI) were independent prognostic factors for DFS, while histological grade, cT classification, cN classification, and age were those for OS. The neck dissection showed no significant survival benefit for patients with cN0. Lung was the most common site of distant metastasis (16.7%).

CONCLUSIONS

Histological grade, cT classification, cN classification, age, and PNI were independent prognostic factors of patient with SGC, which should be the main considerations for making therapeutic regimens. Our study also verifies the neck dissection of patient with cN0 is unnecessary, and postoperative radiotherapy (PORT) is vital for patients with pN+.

HRAS mutation as a diagnostic molecular analysis for epithelial-myoepithelial carcinoma of the parotid gland: A case report

HRAS mutations are frequent genetic alterations in epithelial-myoepithelial carcinoma, and they may be useful as ancillary molecular tests and predictive molecular tests for targeted therapy with tipifarnib.

Mucin 1 promotes salivary gland cancer cell proliferation and metastasis by regulating the epidermal growth factor receptor signaling pathway

Background/purpose

Salivary gland cancer (SGC) is the common malignant tumor of the head and neck region with poor prognosis. Mucin 1 (MUC1) has been reported to be associated with the development of cancer. However, whether MUC1 contributed to the progression of SGC remains to be explored.

Materials and methods

Immunohistochemical analysis was used to explore the expression levels of MUC1 in SGC tissues. Cell proliferation, colony formation, wound healing, transwell, and xenograft assays were performed to examine the effects of MUC1 on SGC in vitro and in vivo.

Results

We found that the expression level of MUC1 was significantly upregulated in SGC tissues, and the expression level of MUC1 was significantly correlated with lymph node metastasis and TNM stage of SGC. Further exploration demonstrated that MUC1 knockdown drastically inhibited, while its overexpression promoted, cell growth, colony formation, migration, and invasion abilities of SGC cells in vitro. MUC1 knockdown significantly inhibited tumor growth in vivo, and vice versa. More importantly, we found that MUC1 promotes malignant phenotypes of SGC cells by regulating the epidermal growth factor receptor (EGFR) signaling pathway.

Conclusion

Our results revealed that MUC1 promotes the development of SGC by mediating the EGFR signaling pathway, which highlights the potential therapeutic target of MUC1/ EGFR in SGC.

Head and neck carcinoma in children: A clinicopathological study of 42 cases

Background/purpose

Cancer is an important part of the global burden of childhood diseases. Head and neck carcinoma in children is rare and related research is limited. This study aimed to investigate the clinicopathological features of childhood head and neck carcinoma.

Materials and methods

Forty-two cases of childhood head and neck carcinoma treated in our institution were reviewed and analyzed.

Results

Median age overall was 11 years. Twenty-three patients (54.8%) were male and 19 (45.2%) were female. Parotid gland location was most common (54.8%). Mucoepidermoid carcinoma and squamous cell carcinoma were the most common histological types (57.1% and 11.9%, respectively). Two patients had a history of bone marrow transplantation and two had a history of odontogenic keratocyst. The recurrence rate after treatment was 8.6%.

Conclusion

Early diagnosis and treatment and close follow-up of childhood head and neck carcinoma are warranted to prevent recurrence and improve clinical outcome.

Defining the clinical characteristics of mammary analog secretory carcinoma of the salivary gland: Analysis of the National Cancer Database

Objectives

Mammary analog secretory carcinoma (MASC) is a classification of salivary gland tumors, recently included within the term secretory carcinoma. Previous descriptions of this diagnosis have largely consisted of case reports and case series with few studies investigating its clinical characteristics as compared to non-MASC tumors. Our objective was to use a large patient database to compare the clinical characteristics of mammary analog secretory carcinoma vs. non-mammary analog secretory carcinoma salivary gland tumors.

Methods

The National Cancer Database was queried between September and October 2022 for histological diagnosis of mammary analog secretory carcinoma and non-MASC salivary tumors. Patients diagnosed with mammary analog secretory carcinoma and non-mammary analog secretory carcinoma salivary tumors between the period of 2004 through 2019 were included in this analysis. Various demographic and clinical variables were abstracted from the database and compared using Wilcoxon rank sum and chi-square tests. Survival was compared between cohorts using Cox proportional hazards regression.

Results

Overall, compared to non-mammary analog secretory carcinoma diagnoses (n = 47668), mammary analog secretory carcinoma tumors (n = 384) affected younger individuals, displayed favorable pathologic staging and tumor grade, and were less likely to invade surrounding tissues. Patients with mammary analog secretory carcinoma tumors also received treatment more quickly following diagnosis compared to patients with non-mammary analog secretory carcinoma tumors. The risk of death was 4.3 times greater for non-mammary analog secretory carcinoma diagnoses when adjusted for patient variables (hazard ratio = 4.3, 95% confidence interval [2.37-7.71], p < 0.001).

Conclusions

Clinically, mammary analog secretory carcinoma salivary tumors have a more indolent course compared to other salivary cancers. Additional studies are needed to determine the natural history of this tumor type.

Prognostic factors in surgically treated malignant salivary gland tumors

OBJECTIVES

To identify prognostic factors for evidence-based risk stratification in malignant salivary gland tumors.

METHODS

This retrospective study identified 162 patients who presented with malignant salivary gland tumors between 2010 and 2020. Final analysis included 91 patients who underwent surgical treatment at our institution and were followed-up for ≥ 1 year. Medical records were reviewed and patients were categorized according to their risk profile.

RESULTS

This study included 91 patients (51 males, 40 females, mean age 61 years). The most frequent entities were adenoid cystic carcinoma (n = 13, 14.3%) and mucoepidermoid carcinoma (n = 12, 13.2%). Kaplan-Meier analysis demonstrated a five-year overall survival (OS) of 66.2% and a recurrence-free survival (RFS) of 50.5%. Age > 60 years (p = 0.011), categorization into high-risk group (p = 0.011), UICC stage (p = 0.020), T stage (p = 0.032), grading (p = 0.045) and vascular invasion (p < 0.001) were significantly associated with OS; age > 60 years (p = 0.014), categorization into high-risk group (p < 0.001), UICC stage (p = 0.021), T stage (p = 0.017), grading (p = 0.011), vascular invasion (p = 0.012) and lymphovascular invasion (p < 0.001) were significantly associated with RFS. Multivariate Cox regression with backward elimination identified T stage (HR 1.835; 95% CI 1.187-2.836; p = 0.006) and grading (HR 2.233; 95% CI 1.113-4.480; p = 0.024) as significant factors for OS. Grading (HR 2.499; 95% CI 1.344-4.648; p = 0.004) was confirmed as a significant factor for RFS.

CONCLUSION

Considering the risk of recurrence and distant metastasis in malignant salivary gland tumors, locoregional surgical control may not be sufficient and adjuvant therapies such as radiotherapy and/or systemic therapies should be considered.

Postoperative Radiation Therapy Refusal in Major Salivary Gland Cancers

OBJECTIVE

Major salivary gland cancers (MSGCs) are often treated with primary surgery followed by adjuvant therapy for high-risk pathology. Patients with these cancers may opt out of recommended postoperative radiation therapy (PORT) for many reasons and consequently may suffer worse outcomes.

STUDY DESIGN

Retrospective cohort study.

SETTING

National Cancer Database.

METHODS

Patients diagnosed with MSGC from 2004 to 2016 were identified, and overall survival and risk factors for refusal of recommended PORT were analyzed based on demographic, socioeconomic, and clinical factors. Multivariable logistic regression and a Cox model were used to conduct the analysis.

RESULTS

211 out of 4704 qualifying patients (4.5%) refused recommended PORT. Multivariable analysis demonstrated increased PORT refusal for age >74 years (odds ratio OR 4.34, confidence interval [CI] [2.43-7.85]), Asian race (OR 2.25, CI [1.10-4.23]), and certain facility types (comprehensive cancer center, OR 2.39, CI [1.08-6.34]; academic research program, OR 3.29, CI [1.49-8.74]; and integrated network cancer program, OR 2.75, CI [1.14-7.7]). N2 stage was associated with decreased PORT refusal (OR 0.67, CI [0.45-0.98]). The 5-year overall survival for patients who received and refused PORT were significantly different at 65.8% and 53.8%, respectively (p < .001). When controlling for several factors, PORT refusal was independently associated with significantly lower overall survival (HR 1.54, CI [1.21-1.98]).

CONCLUSION

Patient refusal of recommended PORT in MSGC is rare, associated with various disease and socioeconomic factors, and may decrease overall survival. Our findings can assist clinicians in counseling patients and identifying those who may be more likely to opt out of recommended PORT.

Impact of Amplified Oncogenes on Salivary Gland Carcinomas

In normal epithelia, proto-oncogenes regulate critical intra- or intercellular functions, including cell growth and proliferation, apoptosis, and signaling transduction from the cell periphery (extracellular space) to the nucleus mediated by different pathways. Oncogenes are the mutated or amplified forms of the corresponding proto-oncogenes that are crucially involved in cell neoplastic and malignant transformation during carcinogenesis. Salivary gland carcinomas (SGCs) demonstrate a variety of histogenetic types. They are characterized by a broad spectrum of chromosomal and gene alterations. In particular, amplifications in specific genes [human epidermal growth factor receptor 2 (HER2), human epidermal growth factor receptor 4 (HER4), epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), Mouse double minute 2 homolog (MDM2), androgen receptor (AR), programmed death (ligand 1 (PD-L1), neurogenic differentiation factor 2 (NEUROD2), phosphatidylinositol 3,4,5-trisphosphate-dependent RAC exchanger 1 protein (PREX1), cyclin-dependent kinase4/6 (CDK4/6), proline-rich acidic protein 1 (PRAP1), kell antigen system (KEL), glutamate receptor subunit epsilon 2 (GRIN2D), Ewing sarcoma RNA-binding protein 1 (EWSR1), MYC proto-oncogene (MYC)] combined or not with chromosomal numerical imbalances (aneuploidy/ polysomy/monosomy) form different genetic signatures affecting the response to monoclonal antibody-based, oncologicaly targeted regimens. Different SGC histotypes demonstrate specific combinations of mutated/amplified genes that modify their clinicohistological features. In the current molecular review, we present the most important amplified oncogenes and their impact on the biological behavior of SGCS.

Combination chemotherapy with taxane and platinum in patients with salivary gland carcinoma: a retrospective study of docetaxel plus cisplatin and paclitaxel plus carboplatin

Background

Despite advances in precision medicine, most patients with recurrent or metastatic salivary gland carcinoma still need conventional chemotherapies, such as the combination of taxane and platinum. However, evidence for these standardized regimens is limited.

Methods

We retrospectively reviewed patients with salivary gland carcinoma treated with a taxane and platinum, which contained docetaxel at a dose of 60 mg/m2 plus cisplatin at a dose of 70 mg/m2 on day 1, or paclitaxel at a dose of 100 mg/m2 plus carboplatin at a dose of area under the plasma concentration-time curve = 2.5 on days 1 and 8 (both on 21-day cycles), between January 2000 and September 2021.

Result

Forty patients with ten adenoid cystic carcinomas and thirty other pathologies were identified. Of these, 29 patients were treated with docetaxel plus cisplatin and 11 with paclitaxel plus carboplatin. For the total population, the objective response rate (ORR) and median progression-free survival (mPFS) were 37.5% and 5.4 months (95% confidence interval: 3.6-7.4 months), respectively. On subgroup analysis, docetaxel plus cisplatin provided favorable efficacy compared with paclitaxel plus carboplatin (ORR: 46.5% vs. 20.0%, mPFS: 7.2 vs. 2.8 months), and the findings were well retained in patients with adenoid cystic carcinoma (ORR: 60.0% vs. 0%, mPFS: 17.7 vs. 2.8 months). Grade 3/4 neutropenia was relatively frequent in the docetaxel plus cisplatin (59% vs.27%), although febrile neutropenia was uncommon (3%) in the cohort. No treatment-related death was seen in any case.

Conclusion

The combination of taxane and platinum is generally effective and well-tolerated for recurrent or metastatic salivary gland carcinoma. In contrast, paclitaxel plus carboplatin appears unfavorable in terms of efficacy in certain patients, such as those with adenoid cystic carcinoma.

Acinic cell carcinoma of the oral and maxillofacial region: an international multicenter study

The aim of this study was to describe the prevalence, clinicopathological, and prognostic features of acinic cell carcinoma (AciCC) of the oral and maxillofacial region. AciCC cases were retrospectively retrieved from 11 pathology centers of three different countries. Medical records were examined to extract demographic, clinical, pathologic, and follow-up information. A total of 75 cases were included. Females (65.33%) with a mean age of 45.51 years were mostly affected. The lesions usually presented as an asymptomatic (64.28%) nodule (95.66%) in the parotid gland (70.68%). The association of two histopathological patterns was the most common finding (48.93%) and the tumors presented mainly conventional histopathological grades (86.11%). Surgical treatment was performed in the majority of the cases (59.19%). Local recurrence was observed in 20% of the informed cases, regional metastasis in 30.43%, and distant metastasis in 12.50%. The statistical analysis showed that the cases with a solid histopathological pattern (p=0.01), high-grade transformation (p=0.008), recurrence (p=0.007), and regional metastasis (p=0.03) were associated with poor survival. In conclusion, high histopathological transformation, presence of nodal metastasis, and recurrence were prognostic factors for AciCC of the oral and maxillofacial region.

Clinicopathological correlation of Cathepsin K expression in salivary gland carcinomas; relation to patients` outcome

BACKGROUND

Salivary gland carcinomas (SGCs) represent various groups of tumors that demonstrate marked diversity in their prognosis owing to different histology and clinical characteristics. One of the poor prognostic indicators is distant metastasis which is considered the major reason for death in SGC patients. Discovering new biomarkers is urgently required to aid in the detection of cancer onset and progression. Cathepsin K (CTSK), the lysosomal cysteine protease has a principal role in cancer invasion and progression through interaction with the tumor microenvironment, degradation of extracellular membrane proteins and destruction of the elastic lamina of blood vessels. In the English literature, little information was present about the role of CTSK in SGCs. The current study aimed to assess the immunohistochemical expression of CTSK in SGCs and correlate its expression to different clinicopathologic parameters.

METHODS

The retrospective study applied to 45 cases of SGCs categorized as high-grade (33 cases) and low-grade SGCs (12 cases) following the criteria of WHO classification (2017) of head and neck tumors. All patients` clinicopathological and follow-up records were retrieved. The following statistical tests were used to study the variance of CTSK expression in SGCs concerning different clinicopathological parameters; Pearson`s Chi-square test, unpaired two-tailed student t-test, One-way ANOVA, and Post Hoc tests. Disease-free survival (DFS) and Overall survival (OS) were calculated and displayed with the Kaplan-Meier strategy and analyzed with the log-rank test. Univariate and multivariate survival analyses were performed with Cox regression. A P-value lesser than 0.05 was considered statistically significant.

RESULTS

Strong CTSK expression was significantly related to high-grade SGCs (P = 0.000), large infiltrating carcinomas (P = 0.000), presence of nodal (P = 0.041) and distant metastasis (P = 0.009), advanced TNM clinical stage (P = 0.000), the incidence of recurrence (P = 0.009), and reduced DFS (P = 0.006). Distant metastasis was the independent predictor for DFS using Cox regression model.

CONCLUSIONS

CTSK has a great role in cancer progression by triggering many signaling pathways. Its level in cancerous tissue is considered an effective index for predicting the severity and prognosis of cancer. Therefore, we indicate its utility as a prognostic tool and therapeutic target for cancer treatment.

TRIAL REGISTRATION

Retrospectively registered.

Intraductal Carcinoma: The Carcinoma In Situ of the Salivary Gland

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

Clinicopathological Predictors of Survival for Parotid Mucoepidermoid Carcinoma: A Systematic Review

OBJECTIVE

Various prognostic factors are associated with the survival of patients with parotid mucoepidermoid carcinoma (MEC). The aim of this systematic review is to summarize the clinical and pathologic prognostic factors on survival outcomes in patients with parotid MEC.

DATA SOURCES

Articles published from database inception to July 2020 on OVID Medline, OVID Embase, Cochrane Central, and Scopus.

REVIEW METHODS

Studies were included that reported clinical or pathologic prognostic factors on survival outcomes for adult patients with parotid MEC. Data extraction, risk of bias, and quality assessment were conducted by 2 independent reviewers.

RESULTS

A total of 4290 titles were reviewed, 396 retrieved for full-text screening, and 18 included in the review. The average risk of bias was high, and quality assessment for the prognostic factors ranged from very low to moderate. Prognostic factors that were consistently associated with negative survival outcomes on multivariate analysis included histologic grade (hazard ratio [HR], 5.66), nodal status (HR, 2.86), distant metastasis (HR, 3.10-5.80), intraparotid metastasis (HR, 13.52), and age (HR, 1.02-6.86). Prognostic factors that inconsistently reported associations with survival outcomes were TNM stage, T classification, and N classification.

CONCLUSION

Histologic grade, nodal status, distant metastasis, intraparotid metastasis, and age were associated with worse survival outcomes. These prognostic factors should be considered when determining the most appropriate treatment and follow-up plan for patients with parotid MEC.

Differential diagnosis of parotid gland tumors using apparent diffusion coefficient, texture features, and their combination

OBJECTIVES

Warthin's tumors (WT) and pleomorphic adenomas (PA) are the commonest parotid gland tumors; however, their differentiation remains difficult. This study aimed to investigate the utility of the apparent diffusion coefficient (ADC) value, texture features, and their combination for the differential diagnosis of parotid gland tumors.

METHODS

Patients who underwent magnetic resonance imaging (MRI) between April 2008 and March 2021 for parotid gland tumors were included and divided into two groups according to the tumor type: WT and PA. The tumor types were used as predictor variables, while the ADC value, texture features, and their combination were the outcome variables. Texture features were measured on short tau inversion recovery (STIR) images and selected using the Fisher's coefficient method and probability of error, and average correlation coefficients. The Mann-Whitney U-test was used to analyze bivariate statistics. Receiver operating characteristic curve analysis was used to assess the ability of the ADC value, texture features, and their combination to distinguishing between the two tumor types.

RESULTS

A total of 22 patients were included, 11 in each group. The ADC value, 10 texture features, and their combination were significantly different between the two groups (p < .001). Moreover, all three variables had high area under the curve values of 0.93-0.96.

CONCLUSION

The ADC value, texture features, and their combination demonstrated good diagnostic ability to distinguish between WTs and PAs. This method may be used to aid the differential diagnosis of parotid gland tumors, thereby promoting timely and adequate treatment.

Uncommon Sites of Lymphoepithelial Carcinoma in Head and Neck Region

We present two cases of Lymphoepithelial carcinoma (LEC) which were found in uncommon sites, the first at the right parotid salivary gland and the second at the base of the tongue. Both patients presented with painless neck masses and were diagnosed with histologic analysis. There is an association with Epstein-Barr virus (EBV) infection in the first case, but none was found in the second case. The primary and metastatic LEC are indistinguishable through histological studies. Therefore, examination of nasopharynx and neck imaging is vital to differentiate primary and metastatic LEC in non-nasopharyngeal sites. A collaboration between surgeons and pathologists is essential for accurate diagnosis of LEC. Radiotherapy is the main choice of treatment for LEC, similar to the cases in the nasopharynx.

Salivary Gland Tumors in Iran: A Systematic Review of 2870 Cases Based on the New WHO Classification

Background & Objective

There is no consensus on the prevalence of salivary gland tumors (SGTs) in Iran. Thus, we systematically reviewed the literature about the prevalence of SGTs in Iran and applied the last world health organization (WHO) classification.

Methods

The systematic literature search was performed in EMBASE, Scopus, PubMed MEDLINE, Google Scholar, Scientific Information Database (SID), and Magiran; we searched for "salivary gland," "tumor," "prevalence," and "Iran" until 1 March 2021. The studies included were written in the English and Farsi languages. The weighted mean prevalence of SGTs was calculated as prevalence (%) * (N/the sum of all N). We used the unpaired Two-sample T-test to compare the weighted means.

Results

A total of 17 studies, including 2870 patients, were selected for the data synthesis. The weighted mean prevalence of benign and malignant tumors was 66% (95% CI: 59-73) and 34% (95% CI: 27-41), respectively. The patients' mean age was reported in 10 out of the 17 studies. The weighted mean age of the patients was 40 (95% CI: 37-42) and 49 (95% CI: 43-55) years for benign and malignant tumors, respectively (P=0.01). Pleomorphic adenoma (PA), followed by Warthin's tumor (WT), was the most prevalent benign tumor. Moreover, the most common malignant tumors were mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (AdCC).

Conclusion

More than one-third of SGTs in Iran were malignant, which is higher than the reports from Middle Eastern countries. Information about risk factors and the burden of SGTs in Iran is insufficient. Thus, further well-designed longitudinal studies are warranted.

Human β-Defensins in Diagnosis of Head and Neck Cancers

Head and neck cancers are malignant growths with high death rates, which makes the early diagnosis of the affected patients of utmost importance. Over 90% of oral cavity cancers come from squamous cells, and the tongue, oral cavity, and salivary glands are the most common locations for oral squamous cell carcinoma lesions. Human β-defensins (hBDs), which are mainly produced by epithelial cells, are cationic peptides with a wide antimicrobial spectrum. In addition to their role in antimicrobial defense, these peptides also take part in the regulation of the immune response. Recent studies produced evidence that these small antimicrobial peptides are related to the gene and protein expression profiles of tumors. While the suppression of hBDs is a common finding in head and neck cancer studies, opposite findings were also presented. In the present narrative review, the aim will be to discuss the changes in the hBD expression profile during the onset and progression of head and neck cancers. The final aim will be to discuss the use of hBDs as diagnostic markers of head and neck cancers.

A 10-Year Review of Intraoral Salivary Gland Tumor Diagnoses: Diagnostic Challenges and Inter-Observer Agreement

BACKGROUND

Salivary gland tumors (SGT) are a diverse group of neoplasms arising from the major and minor glands. The oral cavity is the most common site for minor SGT (IMSGT), and these lesions frequently pose a challenge to the pathologist due to overlapping histopathological features and limited material for analysis. Our objective was to determine specific clinical and histopathological features associated with challenges in IMSGT diagnoses and pathologists' agreement.

METHODS

We conducted a retrospective analysis of 248 IMSGT received between 2010 and 2019. We evaluated the diagnostic challenge of the cases by stratifying according to whether a definitive, favored, or indeterminate (challenging) diagnosis was provided. Inter-observer agreement and concordance of biopsy diagnoses with the final diagnoses after tumor resection were evaluated.

RESULTS

Of the 248 biopsies, 191 had a definitive diagnosis, 38 favored diagnoses, and 19 were indeterminate. The predominant diagnoses considered for the indeterminate category were pleomorphic adenoma/myoepithelioma (PA), polymorphous adenocarcinoma (PAC), adenoid cystic carcinoma (AdCC), and low-grade adenocarcinoma. Using multivariate analysis of clinical features, younger patient age, smaller tumor size, and larger biopsy size increased the likelihood of a definitive diagnosis (p = 0.014, p = 0.037, p = 0.012). The inter-observer agreement for 68 representative cases was moderate overall (Fleiss's Kappa 0.575) and good for the 40 cases with a definitive diagnosis (Fleiss's Kappa 0.66). Sixty-five biopsy diagnoses were matched with corresponding tumor resection diagnoses and found to show a good concordance (Cramer's V test 0.76). The discordant diagnoses predominantly involved PA, carcinoma exPA, PAC, AdCC, and adenocarcinoma NOS.

CONCLUSION

Diagnostic challenges in IMSGT incisional biopsies were infrequent, especially if multiple pathologists were consulted. PA, PAC, AdCC, and adenocarcinoma NOS were the histologic types more commonly posing diagnostic challenges. Younger patient age, smaller tumor size, and larger biopsy are associated with a definitive diagnosis. This data highlights the importance of appropriate sampling in IMSGT.

MiR-29a-3p inhibits high-grade transformation and epithelial-mesenchymal transition of lacrimal gland adenoid cystic carcinoma by targeting Quaking

BACKGROUND

Lacrimal adenoid cystic carcinoma (LACC) is the most common orbital malignant epithelial neoplasm. LACC with high-grade transformation (LACC-HGT) has higher rates of recurrence, metastasis, and mortality than LACC without HGT. This study investigated the effects of microRNA-29a-3p (miR-29a-3p) in the pathogenesis of LACC-HGT.

METHODS

An Agilent human miRNA microarray was used to screen the differentially expressed miRNAs (DEMs) in LACC and LACC-HGT tumor tissues. Then, the primary cells obtained in previous studies were used to determine the effect of miR-29a-3p.

RESULTS

The expression of miR-29a-3p was abnormally lower in LACC-HGT than in LACC. miR-29a-3p can specifically target the 3' UTR of Quaking mRNA and down-regulate Quaking expression, thereby inhibiting the proliferation, migration, and epithelial-mesenchymal transition of LACC cells.

CONCLUSIONS

This study illustrated that miR-29a-3p functions as a tumor suppressor by down-regulating the expression of Quaking to inhibit the tumorigenesis of LACC cells. This study may also reveal the pathogenesis of HGT in LACC cells and provide a reference for LACC-HGT targeted diagnosis.

Comparison of biological behavior of lacrimal gland adenoid cystic carcinoma with high-grade transformation cells

AIM

To evaluate the differences between human lacrimal gland adenoid cystic carcinoma with high-grade transformation (LACC-HGT) primary cells cultured by high-grade transformation tissue and non-high-grade transformation (non-HGT) primary cells cultured by non-high-grade transformation tissue in proliferation, metastasis, drug susceptibility, and genes.

METHODS

LACC-HGT primary cells were established by tissue block culture, and the 4^th to 10^th generation primary cells were selected as research objects. The cells were preliminarily identified by immunofluorescent staining. The differences between non-HGT and LACC-HGT primary cells in terms of proliferation, metastasis, and drug susceptibility were compared by cell counting kit-8 (CCK-8) assay, wound healing, and drug sensitivity experiments. Differentially expressed genes were screened using mRNA array. Gene expression was analyzed using real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

LACC-HGT primary cells were successfully cultured by tissue block culture. Immunofluorescence staining results showed that cytokeratin (CK) and CK7 expression levels were positive in LACC-HGT primary cells. CCK-8 results showed that the proliferation ability of LACC-HGT cells was significantly higher than that of non-HGT cells. Wound healing experiment showed that the migration ability of LACC-HGT cells was significantly higher than that of non-HGT cells. LACC-HGT cells were also less sensitive to cisplatin and paclitaxel than non-HGT cells. Compared with non-HGT cells, 9566 differentially expressed genes were found in LACC-HGT primary cells, of which 5162 were up-regulated and 4404 were down-regulated. The expression of N-acetylneuraminate pyruvate lyase (NPL), MARVEL domain containing 3 (MARVELD3), syntabulin (SYBU), and allograft inflammatory factor 1 (AIF1) was higher in LACC-HGT cells than in non-HGT cells, whereas that of periostin (POSTN) was lower.

CONCLUSION

LACC-HGT primary cells have faster proliferation, stronger migration ability, and poorer sensitivity to chemotherapy drugs than non-HGT primary cells. The expression of mRNAs in non-HGT and LACC-HGT primary cells are significantly different. These features are speculated to be the reasons why high-grade transformation tissues exhibit higher malignant degree and poorer prognosis than their counterparts.

Molecular Targets in Salivary Gland Cancers: A Comprehensive Genomic Analysis of 118 Mucoepidermoid Carcinoma Tumors

INTRODUCTION

Salivary gland carcinomas (SGC) are histologically diverse cancers and next-generation sequencing (NGS) to identify key molecular targets is an important aspect in the management of advanced cases.

METHODS

DNA was extracted from paraffin embedded tissues of advanced SGC and comprehensive genomic profiling (CGP) was carried out to evaluate for base substitutions, short insertions, deletions, copy number changes, gene fusions and rearrangements. Tumor mutation burden (TMB) was calculated on approximately 1.25 Mb. Some 324 genes in the FoundationOne CDX panel were analyzed.

RESULTS

Mucoepidermoid carcinoma (MECa) mutations were assessed. CDKN2A and CDKN2B GA were common in mucoepidermoid carcinoma (MECa) (52.5 and 30.5%). PIK3CA was also common in MECa (16.9%). ERBB2 amplification/short variants (amp/SV) were found in MECa (5.9/0%). HRAS GA was common in MECa (14.4%) as well. Other targets, including BAP1, PTEN, and KRAS, were noted but had a low incidence. In terms of immunotherapy (IO)-predictive markers, TMB > 10 was more common in MECa (16.9%). PDL1 high was also seen in MECa (4.20%).

CONCLUSION

SGC are rare tumors with no FDA-approved treatment options. This large dataset reveals many opportunities for IO and targeted therapy contributing to the continuously increased precision in the selection of treatment for these patients.

Salivary gland tumors: A 13-year clinicopathologic retrospective study in a Brazilian northeast population

Background

The present study aimed to evaluate the clinicopathologic features of salivary gland tumors (SGTs) in a Brazillian northeast population.

Material and Methods

A retrospective descriptive cross-sectional study was performed (1995-2009). All cases of SGTs diagnosed in a private surgical pathology service in Brazil were reviewed, and clinicopathological data were collected.

Results

A total of 23.258 histopathological records of biopsies were analyzed, and 174 cases were diagnosed as SGTs (0.7%). Of these, 117 (67.2%) were classified as benign, and 57 (32.8%) were malignant. The series comprised 89 females (51.1%) and 85 males (48.9%), with a mean age of 50.2 years (range: 3-96 years) and a roughly equal female-to-male ratio (1:1). Most tumors occurred in the parotid gland (n = 82, 47.1%), followed by the palate (n = 45, 25.9%), submandibular gland (n = 15, 8.6%). Pleomorphic adenoma (n = 83; 70.9%) and mucoepidermoid carcinoma (n = 19, 33.3%) were the most frequent benign and malignant tumors, respectively. After reevaluation of morphology and immunohistochemical analysis, seven tumors (4.0%) were reclassified following the current WHO Classification of the Head and Neck Tumors.

Conclusions

The general features of SGT from the studied Brazilian population were similar to previously published reports in other countries. However, SGTs do not show any sex predilection. Although careful morphological analysis is the key to the correct diagnosis of these tumors, immunohistochemical analysis is essential to establish an accurate diagnosis in the face of challenging cases. Key words:Salivary gland tumors, epidemiology, head and neck pathology.

Bmi-1: A master regulator of head and neck cancer stemness

Head and neck cancers are composed of a diverse group of malignancies, many of which exhibit an unacceptably low patient survival, high morbidity and poor treatment outcomes. The cancer stem cell (CSC) hypothesis provides an explanation for the substantial patient morbidity associated with treatment resistance and the high frequency of tumor recurrence/metastasis. Stem cells are a unique population of cells capable of recapitulating a heterogenous organ from a single cell, due to their capacity to self-renew and differentiate into progenitor cells. CSCs share these attributes, in addition to playing a pivotal role in cancer initiation and progression by means of their high tumorigenic potential. CSCs constitute only a small fraction of tumor cells but play a major role in tumor initiation and therapeutic evasion. The shift towards stem-like phenotype fuels many malignant features of a cancer cell and mediates resistance to conventional chemotherapy. Bmi-1 is a master regulator of stem cell self-renewal as part of the polycomb repressive complex 1 (PRC1) and has emerged as a prominent player in cancer stem cell biology. Bmi-1 expression is upregulated in CSCs, which is augmented by tumor-promoting factors and various conventional chemotherapies. Bmi-1⁺ CSCs mediate chemoresistance and metastasis. On the other hand, inhibiting Bmi-1 rescinds CSC function and re-sensitizes cancer cells to chemotherapy. Therefore, elucidating the functional role of Bmi-1 in CSC-mediated cancer progression may unveil an attractive target for mechanism-based, developmental therapeutics. In this review, we discuss the parallels in the role of Bmi-1 in stem cell biology of health and disease and explore how this can be leveraged to advance clinical treatment strategies for head and neck cancer.

[Comparison of four convolutional neural networks for histopathological diagnosis of salivary gland carcinomas]

BACKGROUND

Malignant salivary gland tumors represent a particular diagnostic challenge due to the large number of histopathological entities, their rare occurrence, and the diverse clinical and histological presentations. The aim of this work is to investigate and compare convolutional neural networks (CNNs) as a diagnostic tool for histological diagnosis of salivary gland cancer.

METHODS

From salivary gland cancer preparations of 68 patients, 118 histological slides were digitized at high resolution. These virtual sections were then divided into small image sections, and the resultant 83,819 images were sorted into four categories: background, connective tissue, non-neoplastic salivary gland tissue, and salivary gland cancer tissue. The latter category grouped the entities adenoid cystic carcinoma, adenocarcinoma (not otherwise specified), acinar cell carcinoma, basal cell carcinoma, mucoepidermoid carcinoma, and myoepithelial carcinoma. The categorized images were then processed in a training, validation, and test run by the ImageNet pretrained CNN frameworks (Inception ResNet v2, Inception v3, ResNet152, Xception) in different pixel sizes.

RESULTS

Accuracy values ranged from 18.8% to 84.7% across all network architectures and pixel sizes, with the Inception v3 network achieving the highest value at 500 × 500 pixels. The recall values/sensitivity reached up to 85% for different pixel sizes (Inception v3 network at 1000 × 1000 pixels). The minimum F1 score achieved was 0.07 for the Inception ResNet v2 and the Inception v3 at 100 × 100 pixels each, the maximum F1 score achieved was 0.72 for the Xception at 1000 × 1000 pixels. Inception v3 was the network with the shortest training times, and was superior to all other networks at any pixel size.

CONCLUSION

The current work was able to demonstrate the applicability of CNNs for histopathological analysis of salivary gland tumors for the first time and provide a comparison of the performance of different network architectures. The results indicate a clear potential benefit for future applications.

Overexpression of LAG3, TIM3, and A2aR in adenoid cystic carcinoma and mucoepidermoid carcinoma

OBJECTIVE

Adenoid cystic carcinoma (AdCC) and mucoepidermoid carcinoma (MEC) are the two most frequent malignancies of salivary glands. This study aims to explore the expression and migration of LAG3, TIM3, and A2aR in AdCC and MEC, and the potential relationship with oncogenic signaling molecules and immunosuppressive cytokines.

MATERIALS AND METHODS

Custom made human salivary gland tissue microarrays included 81 AdCCs, 52 MECs, 76 normal salivary glands (NSG), and 14 pleomorphic adenoma (PMA) samples. Immunohistochemical analysis of lymphocyte activation gene 3 (LAG3), T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), adenosine 2a receptor (A2aR), oncogenic phosphorylated S6 kinase (p-S6) and ERK_1/2 (p-ERK_1/2 ), and TGF-β1 was performed with salivary gland tissue microarrays of human samples. The correlation of the immunostaining was analyzed based on a digital pathological system, and data were evaluated by hierarchical cluster. Further in vitro studies of knockdown immune checkpoints LAG3, TIM3, and A2aR were carried out by siRNA transfection.

RESULTS

The expression levels of LAG3, TIM3, and A2aR were remarkably increased in AdCC and MEC, compared with NSG and PMA samples, but were independent of pathology grade. They were closely correlated with TGF-β1, slightly related to p-ERK_1/2 and p-S6. After the knockdown of immune checkpoints LAG3, TIM3, and A2aR, the migration of SACC-LM cell line was significantly reduced.

CONCLUSIONS

These results suggested that LAG3, TIM3, and A2aR are overexpressed in AdCC and MEC, may promote migration of SACC-LM cell and correlated with TGF-β1 and oncogenic signaling pathways.

[Molecular and genetic studies of polymorphic adenocarcinoma of the salivary gland: literature review and description of a clinical case]

The article summarizes the literature data on the results of clinical, histological and molecular genetic studies of polymorphic adenocarcinoma. It is shown that the diagnosis of polymorphic adenocarcinoma presents difficulties due to the variety of morphological structure of its various components, which may correspond to the characteristics of other tumors of the salivary glands, such as pleomorphic adenoma and adenoid cystic carcinoma. Immunohistochemical markers characteristic of this pathology of the salivary glands are described. The article presents a rare clinical case of a male patient with polymorphic adenocarcinoma. Histological examination revealed perineural invasion and a characteristic immunohistochemical profile of tumor cells: low cell proliferative activity for the Ki-67 protein, a positive reaction to antigens: S100, SOX10, P63 and reverse transcriptase TERT. A study conducted by the FISH method revealed the amplification of the TERC gene, which indicates the malignant nature of this neoplasm. Conducting molecular genetic studies is of paramount importance for the diagnosis of polymorphic adenocarcinoma.

An organoid library of salivary gland tumors reveals subtype-specific characteristics and biomarkers

BACKGROUND

Salivary gland tumors (SGTs) include a large group of rare neoplasms in the head and neck region, and the heterogeneous and overlapping features among the subtypes frequently make diagnostic difficulties. There is an urgent need to understand the cellular mechanisms underlying the heterogeneity and overlap among the subtypes, and explore the subtype-specific diagnostic biomarkers.

METHODS

The tumor tissue and the adjacent normal tissue from the 6 most common types of SGTs were processed for organoid culture which only maintained tumor epithelial cells. Organoids were histologically evaluated based on phenotype markers, followed by transcriptional profiling using RNA-sequencing. The transcriptomic similarities and differences among the subtypes were analyzed by subtype consensus clustering and hierarchical clustering. Furthermore, by comparative transcriptional analysis for these 6 types of SGTs and the matched organoids, the potential diagnostic biomarkers from tumor epithelium were identified, in which two selected biomarkers were evaluated by qPCR and confirmed by immunohistochemistry staining using a tissue microarray.

RESULTS

We generated a biobank of patient-derived organoids (PDOs) with 6 subtypes of SGTs, including 21 benign and 24 malignant SGTs. The PDOs recapitulated the morphological and transcriptional characteristics of the parental tumors. The overlap in the cell types and the heterogenous growth patterns were observed in the different subtypes of organoids. Comparing the bulk tissues, the cluster analysis of the PDOs remarkably revealed the epithelial characteristics, and visualized the intrinsic relationship among these subtypes. Finally, the exclusive biomarkers for the 6 most common types of SGTs were uncovered by comparative analysis, and PTP4A1 was demonstrated as a useful diagnostic biomarker for mucoepidermoid carcinoma.

CONCLUSIONS

We established the first organoid biobank with multiple subtypes of SGTs. PDOs of SGTs recapitulate the morphological and transcriptional characteristics of the original tumors, which uncovers subtype-specific biomarkers and reveals the molecular distance among the subtype of SGTs.

A Subset of Salivary Intercalated Duct Lesions Harbors Recurrent CTNNB1 and HRAS Mutations: A Molecular Link to Basal Cell Adenoma and Epithelial-Myoepithelial Carcinoma?

BACKGROUND

Intercalated duct lesions (IDLs) are benign salivary gland proliferations that resemble normal intercalated ducts and are subdivided into hyperplastic, adenoma or hybrid types depending on circumscription. While IDLs were historically regarded as non-neoplastic, frequent association with basal cell adenoma (BCA) and epithelial-myoepithelial carcinoma (EMC) has raised the possibility that they are neoplastic precursors.

METHODS

In this study, we performed β-catenin immunohistochemistry and targeted molecular analysis on IDLs to clarify their pathogenesis.

RESULTS

We identified 15 IDLs from the parotid glands of eight men and six women with a median age of 65 years (range 42-85 years). These lesions included nine hyperplastic, three adenoma, and three hybrid types. Nuclear β-catenin localization was present in 7 of 13 lesions tested (54%). Next generation sequencing was successfully completed in 12 IDLs, of which seven (58%) had likely oncogenic mutations. These included three recurrent CTNNB1 mutations in hyperplastic (n = 2) and hybrid (n = 1) lesions and two recurrent HRAS hotspot mutations in adenomas.

CONCLUSION

Despite substantial heterogeneity, these findings confirm that a majority of IDLs are genuinely neoplastic, and some demonstrate molecular overlap with both BCA and EMC, supporting their theorized role as precursors to these tumors. Nevertheless, no oncogenic drivers were present in a significant subset of cases, suggesting that some IDLs may be truly reactive and hyperplastic. As such, IDL appear to represent a diverse morphologic and molecular spectrum that include both neoplastic and hyperplastic lesions. Reconsideration of the boundary between IDL and BCA in the future may be necessary to simplify classification.