Adenoid cystic carcinoma of the head and neck: clinicopathologic analysis of 218 cases in a Chinese population

How predominant cell and stroma types harmonize to predict head and neck adenoid cystic carcinoma outcomes?

Adenoid cystic carcinoma (ACC) is an uncommon tumor that usually appears in the major salivary glands of the head and neck region, including the minor glands in the oral cavity, sinonasal tract, and other sites. ACC of the head and neck may have a low-grade histological appearance. This malignant tumor has unusual clinical characteristics such as occasional regional lymph node metastases and a prolonged yet continuously advancing clinical course. Additionally, it is an invasive tumor with perineural invasion, difficult-to-clear margins, metastasis, and localized recurrence. The cribriform and tubular proliferation of basaloid cells, which mostly display a myoepithelial cellular phenotype, are ACC's distinct histologic characteristics. The degree of genetic alterations and aneuploidy observed in tumor genomes are linked to the severity of histologic grade, which correlates with clinical prognosis. The three predominant cell types (PCTs) i.e., conventional ACC (C-ACC), myoepithelial-predominant ACC (M-ACC), and epithelial-predominant ACC (E-ACC)-and their respective applications will be reviewed. The function of extracellular matrix (ECM) components such as laminin, type IV collagen, fibronectin, and tenascin are also emphasized. An attempt has been made to explore the recent molecular diversity, regulatory pathways prevalent in PCT, ECM with its genetic changes, and translational utility with targeted therapies for ACC.

Prognostic factors of palatal adenoid cystic carcinoma: A single-center analysis of 85 cases

Objective

The purpose of this retrospective study was to describe the clinicopathological characteristics of primary adenoid cystic carcinoma (ACC) of the palate and to identify the factors affecting prognosis.

Methods

The medical records of 85 patients with primary ACC of the palate treated with surgery, with or without adjuvant radiotherapy/chemotherapy, from 2009 to 2019 were reviewed. The relationship of different clinical parameters with locoregional recurrence (LR), distant metastasis (DM), and overall survival (OS) were analyzed.

Results

Median follow-up time was 44.6 months. LR and DM rates were 24.7% and 25.9%, respectively, and the 5-year OS and disease-free survival (DFS) rates were 85.9% and 55.1%, respectively. Multivariate analysis showed that positive margins were independently associated with the risk of LR (p < .001). Positive margins (p = .001) and high histological grade (p = .031) were significantly associated with shorter OS.

Conclusion

Positive surgical margins are a strong adverse prognostic factor affecting LR and OS in patients with ACC; apart from that, high histopathological grade is an independent predictor of poor OS.

Level of Evidence

Level 3 (Prognosis - Cohort study).

Prognostic Significance of Histopathological Parameters for Salivary Gland Adenoid Cystic Carcinoma

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor that accounts for approximately 1% of all head and neck cancers. Despite its initial indolent behavior, long-term survival is poor due to locoregional recurrence in approximately 40% and distant metastasis in up to 60% of patients who undergo radical treatment. The histological parameters of ACC and the combination of these parameters in histopathological grading systems provide valuable prognostic information about the clinical course of the disease. Within this context, this review aims to analyze the impact of histopathological parameters, individual or combined in histopathological grading systems of malignancy, on ACC prognosis. Individual histopathological parameters such as solid pattern, presence of tumor necrosis, high-grade transformation, dominance of the epithelial component, presence of perineural and lymphovascular invasion, and positive surgical margins have negative impacts on the survival of patients with ACC. There are currently four histopathological grading systems for ACC; however, few studies have validated these systems and most of them explored small cohorts with short follow-up. Considering that the application of grading systems has been associated with ACC prognosis, a broader validation will allow not only their use for prognostic prediction but also assist in treatment planning.

A Case of Undetermined Adenoid Cystic Carcinoma With Airway Stenosis Treated With Palliative X-Ray Radiotherapy Leading to Significant Improvement in Patient’s General Condition

Primary adenoid cystic carcinoma (ACC) of the upper anterior mediastinum is rarely encountered in clinical practice, and no standard treatment has been established. We performed palliative radiotherapy to improve airway narrowing in a patient with primary ACC of the mediastinum who presented with respiratory distress as their main complaint. As a result of radiotherapy, the ACC was reduced in size, the narrowed airway was opened due to compression by the ACC, and the patient's general condition improved. We present the results of this case with a review of the relevant literature.

Recent Advances, Systemic Therapy, and Molecular Targets in Adenoid Cystic Carcinoma of the Head and Neck

With an incidence of 3-4.5 cases per million, adenoid cystic carcinoma (ACC) of the head and neck is one of the most common tumors of the parotid and sublingual salivary glands. In the clinical course, ACC is shown to have an aggressive long-term behavior, which leads to the fact that radical surgical resection of the tumor with tumor-free margins remains the "gold standard" in treating ACC. Particle radiation therapy and systemic molecular biological approaches offer new treatment options. However, risk factors for the formation and prognosis of ACC have not yet been clearly identified. The aim of the present review was to investigate long-term experience of diagnosis and treatment as well as risk and prognostic factors for occurrence and outcome of ACC.

Current opinions on diagnosis and treatment of adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a rare malignant tumor derived mainly from the salivary glands, representing approximately 1% of all headandneck carcinomasand 10% of all salivary gland neoplasms. ACC displays a paradoxical behavioral combination of an indolent growth pattern but an aggressive progression, with local recurrence and distant metastasis. The propensity of ACC of the head and neck (ACCHN) for perineural invasion and its anatomical location, especially if it extends to the nasal cavity and paranasal sinuses, facilitates tumor involvement in the surrounding structures, such as the orbit, pterygopalatine fossa, Meckel'scave, and cavernous sinus, which can lead to skull base involvement and intracranial extension. Despite advances in molecular mechanisms and diagnostic imaging, ACC treatment remainschallenging due to the lack ofconsensuson treatment patterns. In this review, we aimed toprovideanupdatedinsight intothe understanding of ACCHN by focusing on clinical behavior, imaging diagnosis, pathological features, and therapeutic strategies. We reviewed the molecular mechanisms, especially in ACCHN with perineural invasion, and elaborated on treatment options, including chemotherapy, targeted therapies, and immunotherapy, to establish a comprehensive understanding of ACC to arrive at a policy for proper diagnosis, preoperative evaluation, and therapeutic strategies.

The rate of occult nodal metastasis in submandibular gland malignancies: A case series and meta-analysis

OBJECTIVE

Submandibular gland (SMG) malignancies are exceedingly rare. Lymph node metastasis is one of the most important determinants of outcome in SMG malignancies. The aim of this study was to investigate the overall rate of occult neck nodal metastasis in SMG malignancies.

STUDY DESIGN

The study design is a meta-analysis of all studies on patients with a primary SMG malignancy, without evidence of neck nodal metastasis, who underwent an elective neck dissection (END). The search strategy identified 158 papers that appeared in print from January 1980 to July 2020. All eligible patients from the Tel-Aviv Medical Center were analyzed and consolidated into a case series. A total of 12 retrospective studies that included 306 suitable patients met inclusion criteria.

RESULTS

The risk for occult metastasis in primary SMG malignancies was 0.0% to 50.0%, with a fixed effect model of 19.52% (95% CI, 14.9%-24.5%). The analyzed studies included a wide range of pathologies. The most common malignancies were adenoid cystic carcinoma and mucoepidermoid carcinoma.

CONCLUSIONS

The overall rate of occult neck metastasis in SMG malignancies is relatively high, and an END should be the default intervention in these cases. An END is unwarranted in tumors judged clinically to be low stage and low grade.

Dominant cell type analysis predicts head and neck adenoid cystic carcinoma outcomes

Traditional histological grading for predicting adenoid cystic carcinoma (ACC) outcomes is challenging and unreliable. We explored the relationship between dominant cell type (DCT) and outcomes for ACC of the head and neck to develop a new approach to predicting prognosis. Clinicopathological data were obtained from a retrospective cohort of 167 patients with primary ACC of the head and neck. Using immunohistochemistry markers to determine DCT, tumors were subclassified into three distinct subtypes, epithelial-predominant (E-ACC), myoepithelial-predominant (M-ACC), and conventional (C-ACC). Differences in clinicopathological parameters and clinical outcomes among these subtypes were then analyzed. Compared to that of M-ACC and C-ACC, E-ACC exhibited more aggressive clinicopathological features with predominantly solid components, high-grade transformation, lymphovascular invasion, tumor necrosis (TN), Ki-67 ≥ 30%, and advanced stage of disease. Both E-ACC and M-ACC could present as solid morphological forms, but E-ACC had a significantly worse prognosis than M-ACC. DCT, TN, and disease stage were independent predictors of recurrence-free survival. DCT, TN, age ≥ 50 years, and disease stage were independent predictors for overall survival. In conclusion, DCT was an independent prognostic indicator for both recurrence-free and overall survival for ACC. Our results provide a new approach to predicting prognosis in ACC and a strong pathological basis for clinically optimizing treatment.

Diagnostic discrepancy in second opinion reviews of primary epithelial neoplasms involving salivary gland: An 11-year experience from a tertiary referral center focusing on useful pathologic approaches and potential clinical impacts

AIMS

In the era of precision medicine, accurate pathologic diagnoses are crucial for appropriate management.

METHODS

We herein described the histologic features and clinical impacts of 66 salivary gland epithelial neoplasms in which the diagnosis was altered after expert review.

RESULTS

The most common revised diagnosis was that of salivary duct carcinoma (SDC, n = 12), adenoid cystic carcinoma (n = 12), and myoepithelial carcinoma (n = 10). The most common initial diagnosis was mucoepidermoid carcinoma (n = 19) with SDC being the most common revised diagnosis (7/19). Thirteen salivary gland carcinomas were initially diagnosed as benign entities, whereas five benign tumors were initially interpreted as carcinoma. The change in diagnosis was considered to be clinically significant in 65 (97%) cases.

CONCLUSIONS

Given their rarity, salivary gland neoplasms are prone to diagnostic inaccuracy and discrepancy. A constellation of histologic features and ancillary studies are useful in reaching the correct diagnosis, which can have significant clinical impacts.

Exploration of High-Grade Transformation and Postoperative Radiotherapy on Prognostic Analysis for Primary Adenoid Cystic Carcinoma of the Head and Neck

Background

Despite Adenoid cystic carcinoma (ACC) with cribriform or tubular components being recognized as a potentially indolent malignancy, ACC displaying solid or, more rarely, high-grade transformation (HGT) components is considered a more aggressive variant of the disease. As it is difficult to measure the proportion of the solid component objectively, and the role of HGT in the current grading system remains unclear, the prognostic influence of tumor grading remains controversial. In addition, postoperative radiotherapy (PORT) has been proven to be effective in local control of ACC of the head and neck (ACCHN) with a high rate of nerve invasion and close surgical margin. However it remains to be explored that whether PORT could improve the survival of patients with ACC, particularly those with HGT.

Methods

A series of 73 surgically treated primary ACCHN cases were retrospectively accessed. Immunohistochemical staining was performed to observe the biphasic ductal-myoepithelial differentiation and to identify the HGT components of ACC for tumor grading. The correlation between tumor grading and clinicopathological characteristics was analyzed. Univariate and multivariate prognostic analysis were performed for progression-free survival (PFS) and overall survival (OS).

Results

Of the 73 included cases, 47 were grade I-II ACC and 26 were grade III ACC. Among the grade III cases, 14 with loss of biphasic ductal-myoepithelial differentiation identified by immunostaining were classified as HGT, and could be distinguished from conventional grade III cases. These HGT cases were correlated with a high propensity of lymph node metastases and more advanced stage. Univariate analysis demonstrated that tumor grading, perineural invasion, T stage, stage groups, and PORT were predictors for PFS, whereas tumor grading, margin status, and PORT were predictors for OS. However, only tumor grading and PORT were independent predictors for PFS and OS. The patients with HGT had significantly worse prognosis than those with conventional ACC. Moreover, disease progression tended to occur more frequently in younger patients. Among the patients with HGT, those who received PORT had a longer median survival time than those who did not.

Conclusion

HGT ACC identified by loss of biphasic differentiation should be considered in tumor grading. Tumor grading and PORT were independent predictors for disease progression and OS in surgically treated ACCHN patients.

CASC9 plays a role in salivary adenoid cystic carcinoma in vitro by upregulation of ACLY

OBJECTIVE

The study was designed to explore the role of cancer susceptibility candidate 9 (CASC9) in salivary adenoid cystic carcinoma (SACC) (SACC-83 and SACC-LM) cell malignant phenotypes.

METHODS

Colony formation assay was used to measure cell proliferation. Transwell assay was used to detect cell migration and invasion. Flow cytometry analysis was applied to determine cell cycle distribution and apoptosis. FISH assay revealed the subcellular location of CASC9.

RESULTS

Downregulation of CASC9 inhibited SACC cell proliferation, migration, and invasion, led to cell arrest at G0/G1 phase, and facilitated cell apoptosis. In mechanism, CASC9 bound with microRNA 146b-5p (miR-146b-5p) and negatively modulated miR-146b-5p expression. MiR-146b-5p directly targeted 3' untranslated region of ATP-Citrate Lyase (ACLY) to degrade ACLY in SACC cells. CASC9 upregulated ACLY expression through competitively binding with miR-146b-5p. Furthermore, rescue assays indicated that ACLY overexpression counteracted the effects triggered by CASC9 knockdown on cell proliferation, migration, invasion, and apoptosis in SACC cells.

CONCLUSION

CASC9 facilitated the malignant phenotypes of SACC cells by the regulation of the miR-146b-5p/ACLY axis. These findings might lay foundation for SACC research.

High grade transformation of adenoid cystic carcinoma in the palate: Case report with review of literature

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High Grade Transformation of Adenoid Cystic Carcinoma in the palate is very rare tumor.

•

It represents a challenge in both diagnosis and management, with limited experience available.

•

The microscopic diagnosis and management is challenging, considering the sarcacity of the tumor.

Introduction

Adenoid cystic carcinoma (ACC) is a rare tumor developed in minor salivary glands, the palate being the most common site.

Case presentation

Here, we report a case of a 58-year-old man with a 3-year-growing swelling in the right palate diagnosed with high grade transformation adenoid cystic carcinoma. The exam revealed a 4 cm large mass. A tumor resection with a radical neck dissection was performed.

Discussion

High grade transformation in adenoid cystic carcinoma is recently described by Cheuk et al. in 1999. This transformation has more aggressive behavior than conventional solid ACC and has usually been associated with recurrences, early distant metastasis, and greater mortality.

Conclusion

The aim here is to highlight clinical, histopathological, therapeutic and prognostic aspects of high-grade transformation in ACC with literature review.

Role of Postoperative Radiotherapy in Nonmetastatic Head and Neck Adenoid Cystic Carcinoma

BACKGROUND

Head and neck adenoid cystic carcinoma (ACC) is a rare malignant tumor that is prone to local recurrence. The NCCN Guidelines for Head and Neck Cancers recommend that all patients with ACC receive postoperative radiotherapy (PORT). However, whether PORT can improve local control and which patients can benefit from PORT are unknown. This study aimed to assess the role of PORT and provide individualized suggestions for postoperative therapy in patients with ACC.

PATIENTS AND METHODS

We retrospectively reviewed patients with nonmetastatic head and neck ACC who underwent surgery with or without PORT. Recursive partitioning analysis (RPA) was performed to categorize the patients and predict local recurrence-free survival (LRFS). The survival outcome was compared between non-PORT and PORT groups.

RESULTS

A total of 319 patients were included. PORT was identified as a prognostic factor for LRFS in univariate (P=.01) and multivariate analysis (P<.01). However, it did not improve distant metastasis-free survival, disease-free survival, or overall survival in univariate analysis. RPA categorized patients into 3 prognostic groups: low-risk (negative margin, T1-T2, primary location = major or minor salivary gland), intermediate-risk (negative margin, T1-T2, primary location = other locations instead of a major or minor salivary gland; negative margin, T3-T4; positive margin, without bone invasion), and high-risk (positive margin, with bone invasion). Significant LRFS improvements in the PORT group were observed among intermediate-risk (P<.01) and high-risk patients (P<.05). LRFS improvements among low-risk patients were relatively insignificant (P=.10).

CONCLUSIONS

PORT was shown to be a positive prognostic factor for improved LRFS in ACC. Furthermore, PORT could significantly improve LRFS in intermediate-risk and high-risk patients with ACC, but whether low-risk patients could benefit from PORT needs further study.

Comparison of outcomes using radiotherapy or brachytherapy after resection of primary adenoid cystic carcinoma in oral and maxillofacial regions

We wished to investigate the outcome of surgery combined with external-beam radiotherapy (EBRT) or brachytherapy (¹²⁵I seeds) for the treatment of primary adenoid cystic carcinoma (ACC) of the oral and maxillofacial region. Data of patients with primary ACC were reviewed retrospectively. Patients were divided into EBRT and brachytherapy groups. Wide tumor excision was done to achieve negative margins. Standard radiotherapy in the EBRT group was 60 Gy. A treatment-planning system was used to create implantation plans with a prescribed dose of 60-120 Gy and ¹²⁵I seeds were implanted postoperatively. Kaplan-Meier method and log-rank tests were used to analyze local control and survival. The median duration of followup was 66.1 and 46.8 months for the EBRT group and brachytherapy group, respectively. There was no significant difference in local control, control of metastasis to regional lymph nodes, or control of distant metastasis between the two groups. There was no significant difference in overall survival, disease-specific survival, or disease-free survival in the two groups at 3 years and 5 years. The prevalence of complications in the brachytherapy group was lower than that in the EBRT group. Both methods elicited good treatment effects, but the prevalence of adverse events was lower in the brachytherapy group.

MYB-NFIB Translocation by FISH in Adenoid Cystic Carcinoma of the Head and Neck in Nigerian Patients: A Preliminary Report

Adenoid cystic carcinoma (AdCC) is a relatively rare malignancy of head and neck sites such as the salivary glands, lacrimal gland, sinonasal region, and pharynx and may arise in other exocrine glands. The oncologic event in AdCC is the translocation between MYB proto-oncogene transcription factor (MYB) and nuclear factor I/B (NFIB) resulting in t(6;9)(q22-23;p23-24). We carried out a preliminary evaluation of MYB-NFIB translocation by fluorescence in-situ hybridization on seven archived formalin-fixed paraffin-embedded tissues of AdCC of Nigerian patients and its clinicopathologic features. Only 3 of the 7 cases were successfully hybridized, all featuring MYB-NFIB translocations with a range of 14.7-83.3% of translocated cells in 60 cells examined. The 3 translocation positive cases were located in the maxillary sinus, buccal mucosa and parotid. Their morphologic appearances were cribriform-solid (1) & cribriform (2) and classified as grades III (1) & I (2), respectively. These patients may potentially benefit from MYB-targeted anti-neoplastic therapy.

Adenoid cystic carcinoma cytology: Salivary gland and nonsalivary gland

OBJECTIVES

Adenoid cystic carcinoma (ACCA) is an uncommon primary malignancy of salivary glands and rarely nonsalivary tissue. This study aims to evaluate the diagnostic accuracy of ACCA on fine needle aspiration (FNA) material and the associated challenges.

METHODS

A search on electronic pathology database from 2006 to 2016 at The Johns Hopkins Hospital found 83 cytology specimens diagnosed as ACCA, 49 with histology follow-up.

RESULTS

Fifty-two females and 31 males were found ranging from 37 to 95 years old (mean 62.5). The tumor size was 1 to 11.5 cm (mean 3.4). FNAs were performed on 46 salivary glands (54.88%), 12 head and neck masses (14.45%), 9 lymph nodes (10.84%), 9 tracheas/lungs (10.84%), 4 vaginal/perineum/gluteal masses (4.82%), and one for each kidney, liver and abdominal/pelvic mass (1.21%). 83 FNA diagnoses revealed 3 nondiagnostics (3.61%), 20 neoplasms with unspecified features (24.10%), 30 basaloid neoplasms (36.14%), 18 ACCA (21.69%), and 12 other malignancies (14.46%). The accuracy of FNA in diagnosis of ACCA comparing to histologic follow-up in 49 cases was 87.5% sensitivity, 66.67% specificity, with 92.11% positive predictive value and 54.55% negative predictive value. The most common mimicker was pleomorphic adenoma.

CONCLUSION

ACCA can be diagnosed not only in the salivary gland FNAs, but also respiratory tract, intra-abdominal, kidney, and gynecologic regions. FNA is a preferred technique to assess mass lesions. However, a diagnosis of ACCA on FNA material should be rendered with caution since there are benign and malignant neoplasms with overlapping features. Awareness of prior medical history and ancillary studies can improve the diagnosis.

Prognostic Factors and Survival in Adenoid Cystic Carcinoma of the Head and Neck: A Retrospective Clinical and Histopathological Analysis of Patients Seen at a Cancer Center

Adenoid cystic carcinoma (AdCC) is a rare malignancy that accounts for approximately 1% of all head and neck cancers. This neoplasm is characterized by slow but often relentless growth and dissemination. Our aim was to retrospectively evaluate the clinical-pathological features of patients diagnosed with head and neck AdCC and to identify possible prognostic factors. This retrospective observational study analyzed 87 cases of AdCC of the head and neck. Clinical parameters (tumor size, lymph node and distant metastasis, clinical stage, and survival) were obtained from the records. Survival curves were constructed using the Kaplan-Meier method. A p value ≤ 0.05 was considered significant. There was a slight predominance of cases diagnosed in female patients (54%). The mean age at diagnosis was 51.5 years. Analysis using Cox's proportional hazards model considering 10-year disease-specific survival identified histologic pattern and presence of perineural invasion as independent prognostic variables. Primary tumor size and distant metastasis were prognostic predictors of 5- and 10-year disease-free survival. Detailed analysis of the association between clinical-pathological parameters and prognosis can assist professionals with cancer treatment planning and adequate patient management. Considering the long-term aggressive behavior of AdCC, rigorous patient follow-up is important to identify possible locoregional or distant recurrences.

Prognostic factors and overall survival in a 15-year followup of patients with malignant salivary gland tumors: a retrospective analysis of 193 patients

INTRODUCTION

Malignant tumors of the salivary glands are uncommon pathological entities, representing less than 5% of head and neck neoplasms. The prognosis of patients with malignant tumors of the salivary glands is highly variable and certain clinical factors can significantly influence overall survival.

OBJECTIVE

To analyze the clinicopathologic and sociodemographic characteristics that influence survival in patients with malignant tumors of the salivary glands METHODS: This retrospective study analyzed sex, age, race, education level, tumor location, tumor size, lymph node involvement, distant metastasis, margin status, treatment type, marital status, method of health care access and 15-year overall survival in 193 patients with malignant tumors of the salivary glands. The X², log-rank Mantel-Cox, multinomial regression and Cox logistic regression tests were used (SPSS 20.0,p < 0.05).

RESULTS

The most common histological types were adenocarcinoma (32.1%), adenoid cystic carcinoma (31.1%) and mucoepidermoid carcinoma (18.7%). The 15-year overall survival rate was 67.4%, with a mean of 116±6 months. The univariate analysis revealed that male sex (p = 0.026), age > 50 years (p=0.001), referral origin from the public health system (p=0.011), T stage (p= 0.007), M stage (p< 0.001), clinical stage (p< 0.001), compromised surgical margins (p= 0.013), and chemotherapy (p< 0.001) were associated with a poor prognosis. Multivariate analyses also showed that age > 50 years was independently associated with a poor prognosis (p= 0.016). The level of education was the only factor more prevalent in older patients (p= 0.011).

CONCLUSIONS

Patients with malignant tumors of the salivary glands older than 50 years have a worse prognosis and an independent association with a low education level.

Tumor with slow-developing and recurring lumps of the external ear with skull base and lung metastasis: A case report

The present case report describes a rare case of recurring lumps on the external ear in a 46-year-old Chinese male with a history of >10 years, who presented with large irregular red lumps on the right temple and with lung and skull base metastasis. The patient had a lesion in the right auricle and experienced recurrence following surgical resection. A thorough systemic evaluation revealed no other obvious abnormalities. The patient was diagnosed with adenoid cystic carcinoma (ACC), a slow-growing form of high-grade adenocarcinoma, and refused any further treatment at the present hospital (The First Affiliated Hospital of Army Medical University). At 2 years post-follow-up, the patient had become more frail but was in good spirits. The present study indicated that ACC is a low-grade and commonly slow-developing malignancy that primarily arises from a salivary gland, with recurring and metastatic characteristics.

High CXCR4 expression in adenoid cystic carcinoma of the head and neck is associated with increased risk of locoregional recurrence

AIM

Treatment options for head and neck adenoid cystic carcinoma (AdCC) are limited in advanced disease. Chemokine receptor type 4 (CXCR4) is present in various tumour types, including AdCC. Upregulation is associated with tumour recurrence and metastasis. New CXCR4-specific diagnostic and therapeutic target agents have recently been available. This study aimed to analyse CXCR4 expression in a cohort of primary head and neck AdCC.

METHODS

After histopathological revision, tumour tissues of 73 consecutive patients with AdCC over 1990-2016 were sampled on a tissue microarray. Slides were immunohistochemically stained for CXCR4 and semiquantitatively scored. Associations between protein expression and cliniopathological parameters were tested. HRs were calculated using a Cox proportional hazard model.

RESULTS

Sixty-six tumours could be analysed. CXCR4 expression was present in 81% of the tumours with a median of 29% (IQR 1-70) positive cells. Expression was univariately correlated to perineural growth (Spearman ρ .26, p=0.04) and bone invasion (Spearman ρ .32, p=0.01), but not with tumour grade.CXCR4 expression in the primary tumour was significantly higher in tumours that recurred as compared with those that did not recur (median 60%, IQR 33-72 vs 12%, IQR 1-70, Kruskal-Wallis p=0.01). After dichotomisation, >25% of CXCR4 expressions proved an independent prognosticator for a reduced recurrence-free survival (RFS) (HR 7.2, 95% CI 1.5 to 72.4, p=0.04).

CONCLUSION

CXCR4 is expressed in the majority of primary AdCCs and independently correlated to worse RFS, suggesting CXCR4 as a target for imaging and therapy purposes in patients with advanced AdCC.

Mass spectrometry-based proteome profile may be useful to differentiate adenoid cystic carcinoma from polymorphous adenocarcinoma of salivary glands

OBJECTIVE

The aim of this study was to determine the proteome of adenoid cystic carcinoma (AdCC) and polymorphous adenocarcinoma (PAc) and to identify a protein signature useful in distinguishing these two neoplasms.

STUDY DESIGN

Ten cases of AdCC and 10 cases of PAc were microdissected for enrichment of neoplastic tissue. The samples were submitted to liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the proteomics data were analyzed by using the MaxQuant software. LC-MS/MS spectra were searched against the Human UniProt database, and statistical analyses were performed with Perseus software. Bioinformatic analyses were performed by using discovery-based proteomic data on both tumors.

RESULTS

LC-MS/MS analysis identified 1957 proteins. The tumors shared 1590 proteins, and 261 were exclusively identified in AdCC and 106 in PAc. Clustering analysis of the statistically significant proteins clearly separated AdCC from PAc. Protein expression 10 times higher in one group than in the other led to a signature of 16 proteins-6 upregulated in AdCC and 10 in PAc. A new clustering analysis showed reverse regulation and also differentiated both tumors.

CONCLUSIONS

Global proteomics may be useful in discriminating these two malignant salivary neoplasms that frequently show clinical and microscopic overlaps, but additional validation studies are still necessary to determine the diagnostic potential of the protein signature obtained.

Lung metastasis in adenoid cystic carcinoma of the head and neck

BACKGROUND

Distant metastasis of adenoid cystic carcinoma (ACC) is most commonly identified in the lung, but risk factors are still on debate.

METHODS

Risk factors for lung metastasis were evaluated by using Cox proportional hazards model and Kaplan-Meier curves.

RESULTS

Of 112 patients, 48% had distant metastasis; 94.4% of whom had lung metastasis. Univariable analysis revealed sublingual or minor salivary gland, tumor size ≥2.5 cm, and perineural invasion as risk factors (hazard ratio [HR]: 1.99 [1.02-3.91], 2.57 [1.19-5.58], and 2.46 [1.28-4.74], respectively), whereas size, perineural invasion, and local recurrence were risk factors in multivariable analysis (HR: 2.29 [1.05-4.96], 2.32 [1.09-4.96], and 2.68 [1.24-5.79], respectively).

CONCLUSION

Sublingual gland or minor salivary glands ACC has a higher risk of lung metastasis. If the site is not considered, the following factors increased the risk of lung metastasis; (a) size ≥2.5 cm, (b) perineural invasion, and (c) local recurrence.

[Study of surgery combined with 125I brachytherapy for adenoid cystic carcinoma of oral and maxillofacial region]

OBJECTIVE

To retrospectively analyze the results of treatment outcome by surgery combined with ₁₂₅I brachytherapy and correlative factors of adenoid cystic carcinoma (ACC).

METHODS

In the study, 75 patients with primary ACC of oral and maxillofacial region were treated by surgery combined with ₁₂₅I seeds brachytherapy. Radical resection or subtotal resection was applied for the tumor. The brachytherapy treatment planning system was used to create implant plans with the prescribed dose of 60 Gy to 120 Gy. The ₁₂₅I seeds were implanted intraoperatively or postoperatively. The regular follow-up was required. The Kaplan-Meier method was used to assess the tumor control rate and the patients' survival rates. Meanwhile, the Cox regression analysis was used to find out the prognostic factors.

RESULTS

Local control rates at the end of 3 and 5 years were as follows: T1-T2, 92.2% and 82.0%; T3-T4, 82.6% and 82.6%; and overall, 90.0% and 78.8%. The disease-free survival rates were 74.9% and 54.3%, respectively. The overall survival rates for all the patients were 86.0% and 79.6%, respectively at the end of 3 and 5 years and were 91.3% and 91.3% for T1-T2 patients vs. 73.9% and 59.7% for T3-T4 patients. Distant metastasis-free survival rates at the end of 3 and 5 years were 84.4% and 76.7%, respectively. The distant metastasis-free survival rates at the end of 3 and 5 years were 83.4% and 79.6% with T1-T2 lesion compared with 86.0% and 67.8% with T3-T4 lesion. According to the COX univariate analysis and multivariate analysis, the risk of local recurrence would be raised by the age. Tumor stage and tumor site were the prognostic factors of the overall survival rates.

CONCLUSION

₁₂₅I brachytherapy conducted as an adjuvant therapy postoperatively of ACC of oral and maxillofacial region can acquire satisfactory localregional control, distant metastasis-free survival, disease-free survival and overall survival. Tumors are prone to recur on the older patients. Patients having advanced tumor stage or tumor located in the nasal cavity or sinuses will suffer lower survival rates.

Analysis of clinicopathological characteristics, MYB rearrangement and prognostic factors in salivary adenoid cystic carcinoma

Recent studies have indicated that a recurrent t(6;9)(q22-23;p23-24) chromosomal translocation in salivary adenoid cystic carcinoma (ACC) results in a MYB proto-oncogene transcription factor-nuclear factor I/B (MYB-NFIB) gene fusion, which has not previously been detected in any non-ACC carcinomas of the head and neck. In the present study, data on clinical factors affecting the survival rate of patients with salivary ACC from a single institution was retrospectively analyzed, and the frequency of MYB gene rearrangement determined. A total of 97 patient cases were analyzed, and young adults presenting with ACC (<40 years old) accounted for 19.6% of all patients (n=19). A total of 70.1% (n=68) displayed neurological symptoms, including pain, paraesthesia, tongue deviation, and facial paralysis. A marked majority of the analyzed tumors (85.6%) displayed evidence of MYB rearrangement. MYB rearrangement was significantly higher in patients with late Tumor-Node-Metastasis (TNM) stage cancer compared with that in patients with early TNM stage (P=0.033), as detected by a dual color MYB break-apart fluorescence in situ hybridization probe. Kaplan-Meier analysis revealed significant differences in patient overall survival (OS) time with regard to age, gender, TNM stage, neurological symptoms, margin status and MYB rearrangement. Specifically, young age was significantly associated with a shorter OS time. In summary, the present study suggested that young patients with salivary ACC presented with a worse prognosis, in contrast to the majority of patients with salivary ACC. Moreover, MYB alterations exhibited a high positive rate in salivary ACC, and therefore, the absence of MYB rearrangements may be associated with a better prognosis.

The MYB/miR-130a/NDRG2 axis modulates tumor proliferation and metastatic potential in salivary adenoid cystic carcinoma

Increasing evidence has emerged to suggest that N-myc downstream-regulated gene 2 (NDRG2) dysregulation participates in a number of tumor biological processes. However, the role of NDRG2 and miRNA-mediated NDRG2 regulation in salivary adenoid cystic carcinoma (SACC) progression remain unknown. Here, we determined that SACC tissues exhibited decreased level of NDRG2, which was associated with poorer rates of overall survival and distant metastasis-free survival. Silencing NDRG2 promoted SACC cell proliferation and metastasis both in vitro and in vivo. MiRNAs have been reported as vital regulators of NDRG2 expression. Based on micronome sequencing of three paired samples of SACC and normal salivary gland tissue and on an online database analysis, miR-130a was identified as a candidate miRNA that potentially regulates NDRG2. We demonstrated that the expression level of NDRG2 was dramatically reduced by exogenous miR-130a. Moreover, a luciferase assay further validated that miR-130a could degrade NDRG2 mRNA by targeting sites in the NDRG2 3'UTR. A rescue experiment suggested that NDRG2 expression could reverse the miR-130a-mediated promotion of cell proliferation and invasion. The expression of miR-130a has been reported to be regulated by certain transcription factors. In the preset study, we verified that the transcription factor MYB acted as the critical driver in SACC-upregulated miR-130a expression directly and induced NDRG2 downregulation in SACC tissues. Additionally, MYB/miR-130a activated the STAT3 and AKT pathways by downregulating NDRG2. These observations suggest that the MYB/miR-130a/NDRG2 axis, which modulates proliferation and metastasis in SACC, provides promising targets for the treatment of SACC.

Cervical lymph node metastases in salivary gland adenoid cystic carcinoma: a systematic review and meta-analysis

Background

The purpose of this research was to determine whether neck dissection is necessary for the adenoid cystic carcinoma (ACC) of head and neck.

Materials and methods

This article screened the abstract and full-text papers that investigated salivary gland primary ACC of head and neck. Two independent reviewers searched for articles published before October 2017 in three databases (Web of Science, PubMed, and Ovid), having no limits in date and language. Statistical data were analyzed statistically by Review Manager 5.3.

Results

In total, 18 studies involving 2993 patients were included in the analysis. Of the 2993 patients, 473 patients had cervical lymph node metastasis, with a merge frequency of 16% (95% CI: 13-19). Among included articles, only 4 involved cervical lymph node occult metastases, with a merge frequency of 14% (95% CI: 9-20). There were 5 articles containing minor salivary glands (MiSGs) involving 370 patients of which 92 patients had cervical lymph node metastases and the merge frequency was 25% (95% CI: 11-38). Moreover, there were 4 studies on major salivary glands involving 904 patients of which 158 patients had cervical lymph node metastases and the merge frequency was 17% (95% CI: 15-20).

Conclusion

Elective neck dissection is unnecessary for all patients with salivary gland ACC of head and neck. Moreover, compared with major salivary glands, MiSGs have a higher cervical lymph node metastases rate in ACC. The overall cervical lymph node metastases rate of MiSGs is 25%, which is enough to attract our attention. Therefore, we suggest that neck dissection might be applied to ACC of MiSGs.

Mortality risk after clinical management of recurrent and metastatic adenoid cystic carcinoma

Background

Management of locoregional recurrence (LRR) and distant metastasis (DM) in adenoid cystic carcinoma (ACC) is guided by limited data. We investigated mortality risks in patients diagnosed and treated for recurrent ACC.

Methods

A retrospective review of ACC patients treated from 1989 to 2016 identified 36 patients with LRR or DM. High-risk disease was defined as skull base involvement (for LRR) or International Registry of Lung Metastases Group III/IV or extrapulmonary site of metastasis (for DM). Kaplan-Meier method, log-rank tests, and Cox proportional hazards were used for time-to-event analysis.

Results

Among 20 LRR and 16 DM patients, the median times to recurrence were 51 and 50 months, respectively. The median follow-up post-recurrence was 37.5 months (interquartile range (IQR)16.5–56.5). Post-recurrence 3-year overall survival (OS) was 78.5%, 73.3% for LRR and 85.1% for DM (p = 0.62). High-risk recurrences were associated with worse 3-year OS (68.8% for high-risk and 92.3% for low-risk, χ2 = 10.4, p = 0.001).

Among LRR patients, 90% had surgery as part of their treatment. Multimodality therapy, age, and histopathologic features (size, margins, solid histology, lymphovascular or perineural invasion) were not associated with PFS or OS. High-risk LRR was the only variable associated with OS (χ2 = 5.9, p = 0.01).

Among DM patients, six were initially managed with observation and ten received surgery, RT, or systemic therapy. Upfront therapy was not associated with improved PFS or OS. High-risk DM was the only variable associated with OS (χ2 = 4.7, p = 0.03).

Conclusions

High-risk LRR and DM were associated with decreased 3-year OS. More effective therapies are needed for high-risk ACC recurrences.

Predictors of Outcome in Adenoid Cystic Carcinoma of Salivary Glands: A Clinicopathologic Study With Correlation Between MYB Fusion and Protein Expression

Adenoid cystic carcinoma (ACC) is the second most common salivary gland malignancy and it has a high rate of recurrences and a poor long-term prognosis. Our aim was to assess the prognostic factors in ACC and study MYB-NFIB fusion and MYB protein expression in a large retrospective cohort of 135 patients with a median follow-up of 6.3 years. The 5- and 10-year local recurrence-free survival (RFS) rate of 94% and 78%, 5- and 10-year distant metastasis survival rate of 77% and 58%, and 5- and 10-year RFS of 66% and 44%. The following features were identified as adverse prognostic factors of RFS on univariate analysis: large tumor size, solid growth pattern, increased mitoses, positive margin, American Joint Committee on Cancer clinical staging, high-grade transformation, vascular invasion, nuclear atypia, open chromatin, prominent nucleoli, and tumor necrosis. However, on multivariate analysis, only increased mitoses (≥5/10 high-power fields), any solid growth pattern, and advanced American Joint Committee on Cancer TNM staging were independent adverse predictors for RFS. MYB immunoexpression and MYB-NFIB translocation were common findings in ACC, occurring in 72% and 59% of the tested ACCs, respectively. The sensitivity and specificity of MYB immunohistochemistry in detecting MYB-NFIB fusion was relatively low at 78% sensitivity and 50% specificity. The high prevalence of alterations leading to high expression of the MYB transcription factor family suggests that targeted approaches developed to suppress the expression of these oncogenic transcription factors and/or the transcriptional activity of these proteins would be a rational therapeutic approach to investigate in ACC.

Clinical Outcomes and Prognostic Factors of Adenoid Cystic Carcinoma of the Head and Neck

BACKGROUND

Adenoid cystic carcinoma (ACC) is a salivary gland malignancy with unpredictable growth and poorly understood prognostic factors.

PATIENTS AND METHODS

A database search of patients treated at a single Institution was used to identify patients with histologically-confirmed ACC. Patient, tumor, and treatment characteristics were examined via review of medical records.

RESULTS

Overall survival of 70 patients identified at 5, 10, and 15 years was 80.4%, 61.3%, and 29.4%, respectively. Disease recurrence was seen in 31.9%; of these, 72.7% developed distant metastasis. Older age, higher stage, skull base involvement, positive margins, and metastatic disease, but not local recurrence, predicted a worse overall survival. Higher stage and skull base disease were also associated with shorter disease-free survival. While lung metastasis was the most common, vertebral metastasis was associated with poorer survival.

CONCLUSION

Disease stage, positive margins, skull base involvement, perineural invasion, time to recurrence, and location of metastasis, but not nodal involvement, could serve as poor prognostic factors in ACC.

Parotid adenoid cystic carcinoma: Retrospective single institute analysis

PURPOSE

Adenoid cystic carcinoma (ACC) is a uncommon salivary malignant tumor. Our aim was to review our experience with parotid ACC, to identify clinical-pathological parameters predictive for outcome.

MATERIALS AND METHODS

We retrospectively reviewed 228 patients affected by parotid gland carcinomas surgically treated at our Institution. Forty-four ACC were included in this study. Multivariate analysis risk models were built to predict recurrence free probability (RFP), distant recurrence free probability (DRFP), overall survival (OS) and disease free survival (DFS).

RESULTS

Twenty-one patients (47.7%) died from ACC and 2.3% for other causes. The 41% presented local-regional recurrence, with a regional-RFP rate of 93%, and the 34% reported distant metastases (DM). The five and ten-year OS rates were 74% and 50%, respectively.

CONCLUSIONS

Recurrences were mainly influenced by the presence of perineural invasion and nerve paralysis, whilst female gender and age<50 were predictors for good prognosis.

Prognostic factors of adenoid cystic carcinoma of the head and neck in carbon-ion radiotherapy: The impact of histological subtypes

PURPOSE

The aim of this study was to evaluate the effect of histological subtypes of head and neck adenoid cystic carcinoma (ACC) on the results of carbon-ion radiotherapy (CIRT).

MATERIAL AND METHODS

Of the 113 patients with ACC who were treated with CIRT between December 2006 and July 2013, 100 patients with identified histological subtypes were enrolled in this study. CIRT at a total dose of 57.6 or 64.0Gy (RBE) was administered in 16 fractions. Histological grading was defined as the presence or absence of a solid growth pattern.

RESULTS

Median follow-up was 60 months. 5-Year local control (LC), overall survival (OS) and distant metastasis free survival (DMFS) of all patients were 68.6%, 74.8% and 65.7%, respectively. On multivariate analysis, the prescribed dose (p=0.001) and gross tumor volume (p=0.002) were significant independent risk factors for LC. No significant difference for local control of solid/non-solid growth patterns was found (p=0.093). Solid growth pattern was an independent risk factor for both OS (p=0.033) and DMFS (p=0.024).

CONCLUSIONS

CIRT appears able to locally control solid growth pattern ACC in the head and neck. Improved intervention is needed to extend DMFS and OS.

Risk factors and prognosis for salivary gland adenoid cystic carcinoma in southern china: A 25-year retrospective study

Adenoid cystic carcinoma (ACC) is characterized by slow growth, frequent local recurrences, and high incidence of distant metastasis (DM). The aim of this study was to evaluate predictive factors for local-regional (LR) recurrence, DM, and survival in ACC.A retrospective review of the medical records for patients with salivary glands ACC from 1990 to 2015 was performed. The clinical parameters were assessed to identify correlations with the development of LR recurrence, DM, and survival of these patients.Among 228 patients who underwent surgery as definitive treatment, 210 (92.1%) were followed up in the study. DM was detected in 64 (30.5%) patients, LR recurrence was detected in 58 (27.6%) patients. The estimated 5, 10, and 15-year overall survival rates were 84.7%, 70.8%, and 34.0%, respectively. Multivariate analysis revealed that the presence of lymphovascular invasion and a high T classification were very strong adverse factors, which independently influenced LR recurrence, DM, and survival of ACC patients. Positive/close margin and N+ status were independent risk factors for DM and LR recurrence, respectively. Survival of ACC patents was also affected by tumor location.Presence of lymphovascular invasion and a high T classification were very strong adverse factors and independent predictors for ACC patients' prognosis, which influenced LR control, DM control, and survival.

Cervical lymph node metastasis in adenoid cystic carcinoma of the major salivary glands

Objective:

To verify the prevalence of cervical lymph node metastasis in adenoid cystic carcinoma of major salivary glands, and to establish recommendations for elective neck treatment.

Methods:

A search was conducted of the US National Library of Medicine database. Appropriate articles were selected from the abstracts, and the original publications were obtained to extract data.

Results:

Among 483 cases of major salivary gland adenoid cystic carcinoma, a total of 90 (18.6 per cent) had cervical metastasis. The prevalence of positive nodes from adenoid cystic carcinoma was 14.5 per cent for parotid gland, 22.5 per cent for submandibular gland and 24.7 per cent for sublingual gland. Cervical lymph node metastasis occurred more frequently in patients with primary tumour stage T3–4 adenoid cystic carcinoma, and was usually located in levels II and III in the neck.

Conclusion:

Adenoid cystic carcinoma of the major salivary glands is associated with a significant prevalence of cervical node metastasis, and elective neck treatment is indicated for T3 and T4 primary tumours, as well as tumours with other histological risk factors.

Population-based trends in outcomes in adenoid cystic carcinoma of the oral cavity

PURPOSE

Adenoid cystic carcinoma (ACC) is a rare malignant epithelial neoplasm of secretory glands of the upper aerodigestive tract. It accounts for 3-5% of head and neck malignancies and most commonly arises from the minor salivary glands of the oral cavity. The clinical behavior of ACC from specific anatomic subsites, including the oral cavity, is not well described in the literature. We aim to elucidate patient demographics, clinicopathologic features, incidence, and survival trends for oral cavity ACC (OCACC).

METHODS

Retrospective population-based analysis of OCACC in the SEER database between 1973 and 2012.

RESULTS

1066 OCACC patients were identified, of which 57.7% were female (P<0.0001). Incidence was 0.049 per 100,000. Whites were most commonly affected (81.1%). The hard palate was the most commonly involved subsite (44.1%). Nodal involvement was seen in 8.4% of cases and distant metastasis was present in 6.2% of cases at the time of presentation. Disease-specific survival (DSS) rates at 1, 5, 10, 15, and 20years were 97.4%, 83.9%, 69.9%, 57.6%, and 46.2%, respectively. Females had a higher 5-year DSS (87.8%) than males (78.4%, P=0.0004). Cases treated with surgery had a favorable prognosis regardless of whether they received radiotherapy (P<0.0001). Nodal involvement reduced 5-year DSS by 51.6% (P<0.0001), while distant metastasis reduced 5-year DSS by 46.4% (P<0.0001).

CONCLUSIONS

OCACC is a rare malignancy with females and whites being more commonly affected. At presentation, regional and distant metastases are uncommon. Poor prognostic indicators include male gender, nonsurgical therapy, nodal involvement, and distant metastasis.

Adenoid cystic carcinoma of the upper airway mimicking a thyroid tumor: A case report

Adenoid cystic carcinoma (ACC) is a rare malignant tumor, reportedly representing <1% of all head and neck cancers. There have been few reported cases of ACC of the upper airway presenting as a midline mass. This is the case report of a 47-year-old female patient who presented with such a midline neck mass. The mass was approached and investigated as a thyroid mass, but was ultimately found to be a tracheal tumor with thyroid invasion. We herein discuss in detail the patient history, investigation and treatment.

High frequency of loss of PTEN expression in human solid salivary adenoid cystic carcinoma and its implication for targeted therapy

Salivary gland tumor (SGT) is one of the least studied cancers due to its rarity and heterogeneous histological types. Here, we reported that loss of PTEN expression was most frequently found in the poorly differentiated, high grade solid adenoid cystic carcinomas. Loss of PTEN expression correlated with activation of mTOR by increased phosphorylated S6 ribosome protein. We further functionally studied the role of PTEN in a pair of human SACC cell lines, SACC-83 and SACC-LM. Reduced PTEN level was correlated with the metastasis potential. When we knocked down PTEN in the SACC-83 cell line, we observed increased proliferation and enhanced migration/invasion in vitro, and increased tumor size in vivo. We further tested the therapeutical effect by applying a PI3K/mTOR inhibitor NVP-BEZ235 to both SACC cell lines. Decreased cell proliferation, increased apoptosis, as well as reduced cell migration/invasion were observed in both cell lines upon the NVP-BEZ235 treatment. Moreover, the NVP-BEZ235 treatment in a SGT xenograft mouse model significantly reduced primary tumor size and lung metastasis. Taken together, our results demonstrated that PTEN is a potent tumor suppressor in human SGTs, and targeting PI3K/mTOR pathway may be effective in the targeted therapy for human SGT patients with loss of PTEN expression.

Adenoid cystic carcinoma of head and neck: clinical predictors of outcome from a Canadian centre

OBJECTIVES

Adenoid cystic carcinoma (acc) is often treated with surgery, with or without adjuvant radiation therapy (rt). We evaluated disease characteristics, treatments, and potentially prognostic variables in patients with acc.

METHODS

Our retrospective analysis considered consecutive cases of acc presenting at a tertiary care hospital between 2000 and 2014. Factors predictive of overall survival (os) and disease-free survival (dfs) were identified by univariate analysis.

RESULTS

The 60 patients analyzed had a mean age of 58 years (range: 22-88 years), with a 2:1 female:male ratio. Tumour locations included the major salivary glands (40% parotid, 17% submandibular and sublingual), the oro-nasopharyngeal cavity (27%), and other locations (16%). Of the 60 patients, 35 (58%) received surgery with adjuvant rt; 12 (20%), rt only; 13 (22%), surgery only. Of 18 patients (30%) who experienced a recurrence within 5 years, 3 (5%) developed local recurrence only, and the remaining 15 (25%), distant metastasis. The 5-year os and dfs were 64.5% [95% confidence interval (ci): 45.9% to 78.1%] and 46.2% (95% ci: 29.7% to 61.2%) respectively. In patients without recurrence, 5-year os was 77% (95% ci: 52.8% to 89.9%), and in patients with recurrence, it was 42.7% (95% ci: 15.8% to 67.6%). Patients treated with rt only had a 5-year os of 9.2%. Predictors of 5-year dfs were TNM stage, T stage, nodal status, treatment received, and margin status; age, nodal status, treatment received, and margin status predicted 5-year os.

CONCLUSIONS

Despite surgery and rt, one third of patients with acc experience distant recurrence. Patients whose tumours are not amenable to surgery have a poor prognosis, indicating a need for alternative approaches to improve outcomes.

Differences in MYB expression and gene abnormalities further confirm that salivary cribriform basal cell tumors and adenoid cystic carcinoma are two distinct tumor entities

BACKGROUND

In practices, some cases of salivary basal cell tumors that consist mainly of cribriform growth pattern are difficult to differentiate from adenoid cystic carcinoma (AdCC). Identification of reliable molecular biomarkers for the differential diagnosis between them is required.

METHODS

Twenty-two cases of cribriform salivary basal cell tumors (at least 10% cribriform pattern present in each tumor) comprising 18 cases of basal cell adenoma (BCA) and four cases of basal cell adenocarcinoma (BcAC) were collected between 1985 and 2008. Twenty cases of cribriform AdCC were retrieved from our archives. MYB protein expression and gene abnormalities were detected in all cases by immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) analyses, respectively.

RESULTS

Neither MYB protein nor split genes were detected in any of the cases of cribriform basal cell tumors, while 55% (11/20) of cases of cribriform AdCC had MYB protein expression. High MYB expression was detected in 81.8% (9/11) cases, while low expression was found in the remaining cases. FISH analysis indicated that nine AdCC tumors with high MYB protein expression were split gene-positive, while MYB gene splitting was not detected in the 11 cases with low or absent MYB protein expression.

CONCLUSION

The molecular changes in AdCC differ from those associated with cribriform basal cell tumors, which further confirms that cribriform basal cell tumors and AdCC are two distinct tumor entities. Simultaneous detection of MYB protein expression and the associated molecular changes could be beneficial in differentiating salivary cribriform basal cell tumors from AdCC.

Low expression of endothelin receptor B (EDNRB) is related to H3K9me3 binding with the EDNRB promoter region and is associated with the clinical T tumor stage in salivary adenoid cystic carcinoma

OBJECTIVE

To investigate the endothelin receptor B (EDNRB) expression in salivary adenoid cystic carcinoma (ACC) and the mechanism of the regulation of EDNRB expression.

STUDY DESIGN

After screening, EDNRB was selected, and the expression was detected using immunohistochemistry in 33 ACC samples (including 6 clinical tumor stage 1 [T1] patients, 13 T2 patients, 9 T3 patients, and 5 T4 patients) and 20 adjacent glands. Interaction between the EDNRB promoter region and histone H3 lysine 9 trimethylation (H3K9me3) was examined using chromatin immunoprecipitation (ChIP) in combination with ChIP-polymerase chain reaction (ChIP-PCR). EDNRB expression in ACC cells treated with chaetocin was detected using quantitative real-time PCR (qRT-PCR) and Western blot tests.

RESULTS

EDNRB expression was lower in ACC than that in adjacent glands (P = .006). The expression of EDNRB in patients with advanced T stage was lower than that in patients with early T stage (P = .024). The low EDNRB gene expression group had more H3K9me3 binding regions in the gene promoter (P = .003). EDNRB gene expression significantly increased in the ACC cell lines after treatment with chaetocin. Chaetocin could reduce the interaction between the EDNRB promoter and H3K9me3.

CONCLUSIONS

H3K9me3 binding to the EDNRB promoter region could reduce the EDNRB expression. Low EDNRB expression played a role in the progression of ACC tumors.

Pattern of recurrent disease in major salivary gland adenocystic carcinoma

This study aims to evaluate the long-term outcome of major salivary gland adenocystic carcinoma (ACC). This is a retrospective review of 54 cases of ACC during a 35-year period from 1974 to 2009 at the Helsinki University Central Hospital, Helsinki, Finland. Medical records and histological samples were reviewed. All patients had a minimum follow-up time of 5 years or until death. Most of the tumours occurred in the parotid gland (n = 30, 56%) followed by submandibular gland (n = 22, 41%) and sublingual gland (n = 2, 4%). Fifty-two patients (96%) were treated with curative intent. All of these patients except one were primarily treated with surgery, and 29 patients (54%) also received postoperative radiotherapy for their primary tumour. Two patients (4%) received palliative radiotherapy. For those treated with curative intent, 32 patients (62%) had disease recurrence. Twenty-four patients (75%) had their first disease recurrence within 5 years and eight patients (25%) later than 5 years. The difference in the length of recurrence-free time interval (<5 vs. >5 years) had a significant impact on 5-year overall survival (OS) and disease-specific survival (DSS). The OS, DSS and disease-free survival (DFS) across stages I-IV varied between 46-100, 50-100 and 46-100%, respectively. Age over 45 years, T stage, and presence of neck metastases had a significant negative prognostic effect. More than half of the patients had recurrent disease. An extended follow-up for these patients seems feasible as most of the distant metastases were detected within a 10-year period.

RASSF1A promoter hypermethylation is a strong biomarker of poor survival in patients with salivary adenoid cystic carcinoma in a Chinese population

In addition to the clinicopathological parameters, molecular biomarkers are becoming increasingly important in the prognostic evaluation of cancer patients. This study aimed to determine the molecular alterations in the RAS association domain family protein1A gene (RASSF1A) in salivary adenoid cystic carcinoma (ACC) and to evaluate the potential of such alterations as prognostic markers. One hundred and sixty-seven ACC tumor tissues and 50 samples of matched normal salivary gland tissues from the same patients were analyzed for RASSF1A promoter methylation status by bisulfite sequencing PCR (BSP) and/or methylation-specific PCR (MSP). Fifty ACC tumor tissues and matched normal salivary gland tissues were analyzed for loss of heterozygosity (LOH) by examining two microsatellite markers (D3S1478, D3S1621) at 3p21. RASSF1A gene mutations were detected by direct sequencing of all six exons in 50 tumor and normal tissue specimens. Over-all, RASSF1A promoter hypermethylation was detected in 35.3% (59/167) of ACC tissues and was associated with histologically solid tumor pattern (P = 0.002) and advanced TNM stage (P = 0.014). RASSF1A LOH was observed in 18.0% (9/50) of cases, and no somatic mutation of RASSF1A was detected in any cases. RASSF1A promoter methylation was associated with the poor over-all survival (Log-rank test, P <0.001) and disease-free survival (Log-rank test, P <0.001) and identified as an independent predicator of over-all patient survival (P = 0.009) and disease-free survival (P <0.001). It was concluded that RASSF1A methylation is involved in the development, differentiation and progression of ACC and is a strong independent biomarker of poor survival in ACC patients in a Chinese population.

Salivary Adenoid Cystic Carcinoma with Contralateral Cavernous Sinus Metastasis: A Rare Adult Tumor in an Adolescent Patient

Adenoid cystic carcinoma (ACC) accounts for only 1% of all malignant head and neck tumors, and rarely affects children or adolescents. We present a 16-year-old female patient who was diagnosed with ACC at 12 years of age. The primary tumor was located in the left parotid gland. Initial treatment consisted of surgical resection and radiation therapy. Less than two years later, she developed recurrent disease in the right cavernous sinus with pulmonary metastases. At the time of this report, she is alive with disease. Both the patient's age and pattern of metastasis are rarely reported in the literature.