Head and neck adenoid cystic carcinoma: what is new in biological markers and treatment?

Solid basal adenoid cystic carcinoma of the breast: A case report and literature review

RATIONALE

Adenoid cystic carcinoma (AdCC) is a rare malignancy of the breast with a low Ki-67 index and good prognosis. Owing to the rarity of breast AdCC, the misdiagnosis rate is as high as 50%, and there is no consensus or recognized guidelines for the treatment of this disease. Therefore, it is necessary to conduct a detailed clinical and pathological analysis in combination with a literature review to improve our understanding, diagnosis, and treatment of the disease.

METHODS

A 68-year-old woman sought medical attention due to a recently increasing mass in the breast. The left breast mass was 1.3 cm × 1 cm in size. We analyzed the morphology, immunohistochemistry, and molecular characteristics of the tumor removed by surgery, and reviewed relevant literature.

DIAGNOSES

Solid basal AdCC of the breast.

INTERVENTIONS

We performed biopsy, immunohistochemistry and molecular testing on surgical resection specimens.

OUTCOMES

Combining morphological and immunohistochemical features, it is consistent with solid basal AdCC of the breast, and Fish detected MYB gene break.

LESSONS

Due to the high misdiagnosis rate of AdCC, accurate histopathological diagnosis is particularly important. At present, breast conserving surgery and local tumor resection are mainly used for the treatment of breast AdCC, and postoperative adjuvant radiotherapy is feasible.

Adenoid Cystic Carcinoma from the salivary and lacrimal glands and the breast: different clinical outcomes to the same tumor

Adenoid cystic carcinoma (ACC) is a biphasic malignant lesion that can develop at various anatomical sites. Salivary and lacrimal ACC lesions have a high risk of local invasion, metastasis, and poor prognosis. In more distant organs, such as the breast, ACC is a rarer and less aggressive lesion. One of the major predictors of mortality of ACC is perineural invasion, which can be seen in 30% of breast lesions, 85% of salivary lesions, and almost 100% of lacrimal gland tumors. The biological differences between these three ACC tumors are still poorly understood. We focused on the current understanding of the genetic variations observed on ACC tumors and prognostic differences associated with distinct anatomical sites. A special effort was made to present the currently available therapies alongside the emerging strategies under development.

Beyond Surgical Treatment in Adenoid Cystic Carcinoma of the Head and Neck: A Literature Review

Introduction

Adenoid cystic carcinoma (AdCC) is a rare tumour as it accounts for about 10% of all salivary gland neoplasms. It occurs in all age groups with a predominance of women, but no risk factors have been identified to date. Although AdCC behaves as a slow-growing tumour, it is characterized by multiple and late recurrences. Therefore, we aim to update the knowledge of the treatment options in advanced and recurrent cases.

Materials and Methods

We performed a systematic literature review to provide a synthesis of the practical knowledge required for AdCC non-surgical management. Altogether, 99 out of the 1208 available publications were selected for analysis.

Results

AdCC is described as a basaloid tumour consisting of epithelial and myoepithelial cells. Immunohistochemistry is useful for diagnosis (PS100, Vimentin, CD117, CKit, muscle actin, p63) and for prognosis (Ki67). Identified mutations could lead to therapeutic opportunities (MYB-NFIB, Notch 1). The work-up is mainly based on neck and chest CT scan and MRI, and PET-CT with 18-FDG or PSMA can be considered. Surgical treatment remains the gold standard in resectable cases. Post-operative intensity modulated radiotherapy is the standard of care, but hadron therapy may be used in specific situations. Based on the available literature, no standard chemotherapy regimen can be recommended.

Conclusion

There is currently no consensus on the use of chemotherapy in AdCC, either concomitantly to RT in a postoperative setting or at a metastatic stage. Further, the available targeted therapies do not yet provide significant tumour response.

Breast adenoid cystic carcinoma: a report of seven cases and literature review

Background

Primary adenoid cystic carcinoma (ACC) of breast is rarely seen clinically. It is a special subtype of triple-negative breast cancer characterized by low expression of Ki-67, low malignant potential, slow progression and favorable prognosis. To date, treatment for this disease is controversial and no consensus is reached. We analyzed clinical manifestations and pathological characteristics of seven primary breast ACC cases and reported in combination with literature review to promote understanding, diagnosis and treatment of this disease.

Case presentation

We collected seven breast ACC cases pathologically diagnosed and treated in Department of breast surgery of the First Affiliated Hospital of China Medical University from January 2015 to December 2018. We organized and summarized the clinical, imaging, pathological and prognostic information and performed statistical analysis. The median age was 60 years (ranging from 54 to 64 years). Tumors of all patients were detected by immunohistochemistry. Molecular types were mostly triple negative (4/7), and Ki-67 expression was low (5/7). Lymph node metastases were absent in all patients received axillary lymph node surgery. Median follow-up time was 39 months (ranging from 25 to 68 months). There was no occurrence of relapse, distant metastasis or death.

Conclusion

Breast ACC is accompanied with favorable diagnosis, which is different from typical triple-negative breast cancer. Accurate diagnosis of ACC is particularly important.

PTEN downregulates WD repeat‑containing protein 66 in salivary adenoid cystic carcinoma

Salivary adenoid cystic carcinoma (SACC) is one of the most common types of salivary gland cancer that causes substantial morbidity and mortality. Despite the substantial health burden of SACC, the molecular mechanisms underlying its development and progression remain poorly understood. We previously reported the loss of phosphatase and tensin homolog (PTEN) expression to be common among SACC tumors, and the PTEN deficiency to be correlated with enrichment of epithelial-mesenchymal transition (EMT) genes based on expression array analysis. The aim of the present study was to investigate further the functional function of WD repeat-containing protein 66 (WDR66), one of the enriched EMT genes, in the context of PTEN deficiency and SACC pathogenesis. WDR66 was identified to be required to maintain the EMT phenotype and the expression of cancer stem cell genes in the context of PTEN deficiency. Furthermore, knockdown of WDR66 decreased cellular proliferation, migration and invasion. Finally, WDR66 expression was identified to be inversely associated with PTEN expression and negatively correlated with the overall survival of patients with SACC. Collectively, the results of the present study revealed a novel function of WDR66 in mediating the progression of PTEN-deficient SACCs, thereby suggesting WDR66 inhibition to be a potential therapeutic approach towards successful management of SACC disease progression, particularly against tumors with decreased PTEN expression levels.

[Management of a tracheal adenoid cystic medico-surgical carcinoma]

Adenoid cystic carcinoma or cylindroma is a rare tumor of the trachea which arises from mucous secreting cells. Its evolution and growth are slow but it is often fatal in the absence of radical treatment. The latter relies on a surgical sleeve resection of the pathological area, with a tracheo-tracheal anastomosis. Therapeutic bronchoscopy plays a crucial role in the clinical improvement of patients before surgery which will be performed under better conditions. For inoperable patients, radiotherapy has proved its efficacy, unlike conventional chemotherapy. The finding of biomarkers expressed by tumor cells could lead to target therapies. This case report illustrates the efficient combination of therapeutic bronchoscopy and surgery for the treatment of adenoid cystic carcinoma affecting central airways.

Adenoid cystic carcinoma: emerging role of translocations and gene fusions

Adenoid cystic carcinoma (ACC), the second most common salivary gland malignancy, is notorious for poor prognosis, which reflects the propensity of ACC to progress to clinically advanced metastatic disease. Due to high long-term mortality and lack of effective systemic treatment, the slow-growing but aggressive ACC poses a particular challenge in head and neck oncology. Despite the advancements in cancer genomics, up until recently relatively few genetic alterations critical to the ACC development have been recognized. Although the specific chromosomal translocations resulting in MYB-NFIB fusions provide insight into the ACC pathogenesis and represent attractive diagnostic and therapeutic targets, their clinical significance is unclear, and a substantial subset of ACCs do not harbor the MYB-NFIB translocation. Strategies based on detection of newly described genetic events (such as MYB activating super-enhancer translocations and alterations affecting another member of MYB transcription factor family-MYBL1) offer new hope for improved risk assessment, therapeutic intervention and tumor surveillance. However, the impact of these approaches is still limited by an incomplete understanding of the ACC biology, and the manner by which these alterations initiate and drive ACC remains to be delineated. This manuscript summarizes the current status of gene fusions and other driver genetic alterations in ACC pathogenesis and discusses new therapeutic strategies stemming from the current research.

Can molecular profiling enhance radiotherapy? Impact of personalized targeted gold nanoparticles on radiosensitivity and imaging of adenoid cystic carcinoma

Personalized molecular profiling has an established role in selection of treatment for metastatic disease; however, its role in improving radiosensitivity and functional imaging has not been evaluated. In the current study, we examined molecular profiling as a tool for designing personalized targeted gold nanoparticles (GNP) to serve as dual-modal tumor radiosensitizers and functional imaging enhancers. To this end, molecular profiling of a patient's salivary gland adenoid cystic carcinoma (ACC) was performed, and anaplastic lymphoma kinase (ALK) mutation was detected. The extracted tumor was subcutaneously injected into mice, which were then treated either with radiation, the specific ALK inhibitor crizotinib, or a combination of therapies. One of these combinations, namely, ALK-targeted GNP (via crizotinib coating), was found to enhance radiation treatment, as demonstrated by a significant decrease in tumor volume over 24 days. In parallel, ALK-targeted GNP substantially augmented tumor visualization via computed tomography. The mechanism of radiosensitivity enhancement was mostly related to a diminished cell repair mechanism in tumors, as demonstrated by proliferating cell nuclear antigen staining. These findings indicate that personalized molecular profiling is an effective technique for enhancing cancer theranostics.

Thioredoxin 1 mediates TGF-β-induced epithelial-mesenchymal transition in salivary adenoid cystic carcinoma

Epithelial-mesenchymal transition (EMT) plays an important role in the invasion and metastasis of salivary adenoid cystic carcinoma (SACC) which is characterized by wide local infiltration, perineural spread, a propensity to local recurrence and late distant metastasis. Our recent studies have disclosed that TGF-β is a crucial factor for EMT in metastatic SACC. In this study, we further uncovered small redox protein thioredoxin 1 (TXN) as a critical mediator of TGF-β induced EMT. Immunohistochemistry analysis revealed significantly higher expressions of TXN, thioredoxin reductase 1 (TXNRD1) and N-cadherin, and lower expression of E-cadherin in human metastatic SACC compared to non-metastatic SACC tissues. Consistently, cultured SACC cells with stable TXN overexpression had decreased E-cadherin and increased N-cadherin as well as Snail and Slug expressions. The enhanced migration and invasion potential of these cells was abrogated by Akt or TXNRD1 inhibitors. Expression of N-cadherin and Akt p-Akt decreased, whereas E-cadherin expression increased in a BBSKE (TXNRD1 inhibitor)-dose-dependent manner. In a xenograft mouse model, TXN overexpression facilitated the metastatic potential of SACC-83 cells to the lung. Our results indicate that TXN plays a key role in SACC invasion and metastasis through the modulation of TGF-β-Akt/GSK-3β on EMT. TXN could be a potential therapeutic target for SACC.

Cytology of the Salivary Glands

Common usage of fine-needle aspirate (FNA) for salivary gland lesions is the preoperative determination of whether a lesion is neoplastic, its lineage, and if neoplastic, whether it is low grade/benign, or high grade. Immunohistochemical stains can be performed on cell blocks to determine lineage and help refine diagnosis, although their performance is not always equivalent to that seen in surgical specimens. Several characteristic translocations have been described in various entities in these categories, and these can be evaluated using fluorescence in situ hybridization. In the future, high-throughput next-generation sequencing panels may further refine cytologic diagnosis in salivary tumors.

Solid Variant of Adenoid Cystic Carcinoma: Difficulties in Diagnostic Recognition

Adenoid cystic carcinoma (ACC) is a malignant neoplasm that mainly affects the salivary glands but has been described in many other anatomical sites. It is composed of basaloid cells with myoepithelial/basal cell differentiation and ductal epithelial cells that proliferate in a fibrous stroma, with variable amounts of myxohyaline material. Three patterns (cribriform, tubular, and solid) occur, and the solid variant is characterized by a predominant compact sheet-like and nested pattern of rounded basaloid cells lacking obvious cribriform or tubular architecture. The solid variant has significant morphological and immunohistochemical overlap with a large range of neoplasms of different lineages, including other carcinomas and sarcomas. We describe a case of solid variant ACC of the paranasal sinuses, which showed an almost entirely solid pattern of growth (in >95% of cells) and which on initial biopsy showed no features of classical ACC. This highlights the potential for diagnostic misinterpretation with a variety of other neoplasms, which is particularly important because of the significant difference in treatment for ACC and tumors in its differential diagnosis.

Genetic alterations in salivary gland cancers

Salivary gland cancers are an incredibly heterogeneous group of tumors that include 24 histologically distinct tumor types. The use of new genetic methods has paved the way for promising advancements in our understanding of the molecular biology underlying each type of tumor. The objective of this review was to highlight common oncogenes, tumor suppressor genes, and cytogenetic and epigenetic changes associated with the most common tumor types: mucoepidermoid carcinoma, adenoid cystic carcinoma, salivary duct carcinoma, mammary analogue secretory carcinoma, hyalinizing clear cell carcinoma, carcinoma ex pleomorphic adenoma, and acinic cell carcinoma. Recent insights into the pathogenesis of each cancer subtype have helped better define and classify these tumors. Further research in salivary gland cancers should focus on determining the key genes involved in the tumorigenesis of each distinct malignancy and identifying individualized chemotherapies directed at these targets. Cancer 2016;122:1822-31. © 2016 American Cancer Society.

Expression and clinical significance of MAGE and NY-ESO-1 cancer-testis antigens in adenoid cystic carcinoma of the head and neck

BACKGROUND

Adenoid cystic carcinoma (ACC) of the head and neck is a rare but highly malignant tumor. Cancer-testis antigens (CTAs) represent an immunogenic family of cancer-specific proteins and thus represent an attractive target for immunotherapy.

METHODS

Eighty-four cases of ACC were identified, the CTAs pan-Melanoma antigen (pan-MAGE; M3H67) and New York esophageal squamous cell carcinoma (NY-ESO-1; E978) were detected immunohistochemically (IHC) and correlated with clinical data.

RESULTS

Expression of NY-ESO-1 was found in 48 of 84 patients (57.1%) and of pan-MAGE in 28 of 84 patients (31.2%). Median overall survival (OS) in NY-ESO-1 positive versus negative patients was 130.8 and 282.0 months (p = .223), respectively. OS in pan-MAGE positive versus negative patients was 105.3 and 190.5 months, respectively (p = .096). Patients expressing both NY-ESO-1 and pan-MAGE simultaneously had significantly reduced OS with a median of 90.5 months compared with 282.0 months in negative patients (p = .047).

CONCLUSION

A significant fraction of patients with ACC show expression of the CTAs NY-ESO-1 and/or pan-MAGE with promising immunotherapeutic implications. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1008-1016, 2016.

Adenoid cystic carcinoma: current therapy and potential therapeutic advances based on genomic profiling

Adenoid cystic carcinoma (ACC) is a rare cancer with high potential for recurrence and metastasis. Efficacy of current treatment options, particularly for advanced disease, is very limited. Recent whole genome and exome sequencing has dramatically improved our understanding of ACC pathogenesis. A balanced translocation resulting in the MYB-NFIB fusion gene appears to be a fundamental signature of ACC. In addition, sequencing has identified a number of other driver genes mutated in downstream pathways common to other well-studied cancers. Overexpression of oncogenic proteins involved in cell growth, adhesion, cell cycle regulation, and angiogenesis are also present in ACC. Collectively, studies have identified genes and proteins for targeted, mechanism-based, therapies based on tumor phenotypes, as opposed to nonspecific cytotoxic agents. In addition, although few studies in ACC currently exist, immunotherapy may also hold promise. Better genetic understanding will enable treatment with novel targeted agents and initial exploration of immune-based therapies with the goal of improving outcomes for patients with ACC.

Airway compromise due to adenoid cystic carcinoma obstructing the distal trachea: a review of current management and clinical trials

An 84-year-old man presented with a 2-month history of intermittent stridor and worsening difficulty in breathing. Chest X-ray and flexible nasendoscopy were unremarkable but following further deterioration a CT scan revealed an obstructing lesion in the distal trachea. Bronchoscopy revealed an infiltrative tumour arising 3 cm above the carina causing 90% obstruction. The mass was biopsied and surgically debrided to leave a patent airway. Histological analysis revealed a diagnosis of adenoid cystic carcinoma. Transthoracic surgical resection was unsuccessful and the patient continues to be effectively managed with periodic bronchoscopic debulking and radiotherapy. This case highlights the diagnostic and therapeutic dilemmas posed by distal tracheal lesions and the need for specialist input for effective management.

Tracheal adenoid cystic carcinoma mimicking a thyroid tumor: A case report

At present, only eight cases of tracheal adenoid cystic carcinomas (ACCs) mimicking thyroid tumors have been reported. Since there are no guidelines available regarding their diagnosis and treatment, they present a significant clinical challenge. In the present study, patient treatment was analyzed to deliver the first concise summary of treatment options in patients with ACC mimicking a thyroid tumor. In addition, all available data regarding molecular abnormalities of this disease have been discussed. The current study presents a case of a 17-year-old patient with a tracheal ACC mimicking a thyroid tumor. The patient was diagnosed in 2007 with a pathological mass between the left lobe of the thyroid and the trachea, and underwent surgery and radiotherapy. In 2010, multiple lesions in the lungs were diagnosed and pulmonary metastasectomy was performed. Following surgery, the patient has been disease-free for almost 30 months. Thyroid tumor biopsy may reveal ACCs. This pathological report requires further investigation of the head and neck in order to confirm if the disease is of tracheal origin. Patients may present with a neck swelling, hoarseness of voice or dysphagia. Surgery must be considered as first-line therapy for all patients with local disease as it may be curative. For palliative treatment chemoradiotherapy based on cisplatin may be effective. The identification of cytogenetics, tumor suppressor genes, oncogenes, epigenetic alterations and mitochondrial abnormalities specific for ACCs is critical to the development of targeted therapies. Thus far, large studies have only reported the transcriptional activator Myb and mammalian target of rapamycin signaling pathway to be disrupted in ACCs.