Adenoid cystic carcinoma: a rare clinical entity and literature review

Genetic Rearrangements in Different Salivary Gland Tumors: A Systematic Review

Salivary gland tumors (SGT) encompass a wide range of neoplasms, each with its own unique histological type and clinical presentation. This review hones in on prevalent subtypes of SGTs, including adenoid cystic carcinoma (ACC), salivary duct carcinoma (SDC), and polymorphous adenocarcinoma (PAC). The articles, identified through specific keywords, were meticulously screened in databases like PubMed, Scopus, Google Scholar, and Web of Science from 2018 to 2023. Eight articles delved into genetic modifications among the selected SGT types. A fusion protein known as MYB-NF1B is typically associated with ACC, promoting cell proliferation while inhibiting apoptosis. The presence of MYB modifications in ACCs is a beacon of hope, as it is linked to a more favorable prognosis. In contrast, SDCs often exhibit HER2 expression. The invasive nature of SGTs contributes to their resistance to treatment. In the case of PAC, the role of PRKD1 is particularly noteworthy. PRKD1, integrated with other genes from the PRKD1/2/3 cluster, helps to differentiate PAC from other diseases. Furthermore, the genetic profiles of KTN1-PRKD1) and PPP2R2A:PRKD1 are distinct. The significant genetic variability among SGTs necessitates meticulous examination. This field is in a constant state of evolution, with new discoveries reshaping our understanding. Genetics is a key player in deciphering SGTs and tailoring treatments. This complex neoplasm demands ongoing research to uncover all genetic influences, thereby enhancing diagnostic methodologies, therapeutic strategies, and patient outcomes.

Adenoid Cystic Carcinoma of the Minor Salivary Glands: A Systematic Review and Meta-Analysis of Clinical Characteristics and Management Strategies

BACKGROUND

Intraoral adenoid cystic carcinoma (ACC) arising from minor salivary glands (MSG) is a rare malignancy associated with delayed diagnosis and unfavorable outcomes. This study aimed to comprehensively review ACC of MSGs, focusing on clinical characteristics, imaging modalities, treatment approaches, and long-term outcomes.

METHODS

A systematic search was conducted in PubMed, Web of Science, and MEDLINE databases to identify relevant articles reporting cases of ACC of MSGs between January 1997 and March 2023. The study was registered in PROSPERO (ID: CRD42023449478). A total of 10 studies that met the inclusion criteria were selected for critical review. In total, 902 patients were diagnosed with ACC of MSGs with an age range of 44.3 to 63 years, and an average age of 56.6 years. The female to male ratio ranges from 1:1 to 2.4:1. Regarding the primary site of ACC, the palate was the most common location, accounting for 30.5% to 83.3%, followed by the buccal mucosa, floor of the mouth, and lip and the retromolar area. For histology, the solid mass pattern was the most prevalent, seen in 95.2% of patients, followed by the cribriform pattern. Regarding treatment modalities, surgery was the most common approach, applied in 76.3% of cases, with a combination of surgery and radiotherapy used in 29.0% of cases. A smaller fraction, 3.2%, received a combination of surgery, chemotherapy, and radiotherapy, and 8.3% underwent radiotherapy alone. Local recurrence rates varied between 1% and 28.5%, and distant metastasis occurred in 18.2% to 33.3% of cases, predominantly to lymph nodes (14.5%). An analysis of overall survival across various stages and patient numbers indicated a 5-year survival rate of 68.0%. The findings of this study provide valuable insights for physicians in making treatment decisions and emphasize the need for ongoing research and collaborative clinical efforts to improve the management and outcomes of this challenging disease.

CONCLUSION

ACC of MSGs is a multifaceted condition typically manifesting as asymptomatic enlargement and ulceration. This disease is marked by distinct histopathological patterns and perineural invasion (PNI). Recognizing these distinctive aspects is key in shaping the treatment plan, which can range from surgical procedures to radiation therapy, chemotherapy, and evolving targeted treatments. Continuous research and collaborative clinical efforts remain critical for ongoing progress in the treatment and management of this challenging condition.

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 torus-like sublingual adenoid cystic carcinoma in a 35-year-old male: Review of literature and case report

Key Clinical Message

The case report describes an adenoid cystic carcinoma occurring at a rare location and the diagnostic pathway. Swellings of the floor of the mouth, whether painful or without subjective symptoms and regardless of consistency, should be taken seriously.

Abstract

Adenoid cystic carcinoma (ADCC) of the sublingual salivary gland only accounts for 2% of all ADCCs. In this study, we report a rare case of ADCC with sublingual salivary gland origin in a 35-year-old man and a comprehensive review of articles published over the past 62 years.

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.

A curious case of metastatic parotid adenoid cystic carcinoma to kidney

A woman in her 60s presented with a 2-week history of non-specific left-sided abdominal pain. She previously underwent a total parotidectomy and adjuvant radiotherapy for left parotid adenoid cystic carcinoma 13 years prior, with a local recurrence 4 years after. Investigations revealed a large left-sided renal mass with appearances of renal carcinoma and no signs of metastatic disease. Pathology following nephrectomy revealed a metastatic adenoid cystic carcinoma.Metastatic disease recurred 11 months postradical nephrectomy to the contralateral kidney and lung, and she was referred to medical oncology for further management.This case history demonstrates the highly aggressive nature of an adenoid cystic carcinoma primary of salivary gland origin with rare metastasis to the kidney.

Spontaneous Regression of the Pulmonary Metastases in Adenoid Cystic Carcinoma of the Parotid Gland: A Case Report

Adenoid cystic carcinoma (ACC) is a rare epithelial tumor of the salivary glands with an indolent course and usually bears a long-term survival rate even when metastasized. Spontaneous regression of such a resistant tumor is an even scarce event. We report a case of a patient with ACC of the parotid gland with pulmonary metastases, which spontaneously resolved following resection and post-surgical radiation of the primary tumor. Among the numerous theories proposed to explain such a phenomenon, immunogenic mechanisms and the abscopal effect are the most plausible explanations in this case.

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.

Adenoid cystic carcinoma of maxillary antrum: A case report

INTRODUCTION

Adenoid cystic carcinoma rarely involves the nose and paranasal sinuses. It is a slowly growing, aggressive malignant tumor with a predisposition for perineural invasion. The study highlights the importance of timely diagnosis and management of adenoid cystic carcinoma.

PRESENTATION OF CASE

Herein, we report a case of adenoid cystic carcinoma of maxillary antrum in a 69 years old female, who presented with an insidious onset of painful right cheek swelling for three months. Biopsy showed the glandular pattern of tumor cells with perineural invasion, suggestive of adenoid cystic carcinoma. Contrast-enhanced computed tomography of paranasal sinuses showed a well-differentiated, irregularly outlined, non-enhancing heterogeneous lesion in the right maxillary sinus with bony destruction, suggesting the malignant nature of the lesion. The mass was surgically excised and histopathological examination further confirmed the diagnosis.

DISCUSSION

Adenoid cystic carcinoma is a rare malignancy of the nose and paranasal sinus, although it is quite common in salivary glands. It should be considered in the differentials in a patient presenting with sinonasal mass, pain, nasal obstruction, epistaxis, and auditory symptoms.

CONCLUSION

As the tumor can be missed clinically owing to its rarity in paranasal sinuses and can present at an advanced stage, early diagnosis and management of adenoid cystic carcinoma are important.

A Contemporary Review of Molecular Therapeutic Targets for Adenoid Cystic Carcinoma

Simple Summary

Adenoid cystic carcinoma (ACC) is a salivary malignancy known for slow growth, a propensity for perineural spread, local recurrence following resection, and indolent distant metastases. Current treatments in recurrent/metastatic (R/M) ACC are generally of limited impact and often palliative in nature. Herein, we review the preclinical and clinical literature on molecular alterations in ACC with the potential for targeted therapeutics. We further review other molecular targets of ongoing investigation and active clinical trials for patients with ACC, offering a contemporary summary and insight into future therapeutic strategies.

Abstract

ACC is a rare malignant tumor of the salivary glands. In this contemporary review, we explore advances in identification of targetable alterations and clinical trials testing these druggable targets. A search of relevant articles and abstracts from national meetings and three databases, including PubMed, Medline, and Web of Science, was performed. Following keyword search analysis and double peer review of abstracts to ensure appropriate fit, a total of 55 manuscripts were included in this review detailing advances in molecular targets for ACC. The most researched pathway associated with ACC is the MYB–NFIB translocation, found to lead to dysregulation of critical cellular pathways and thought to be a fundamental driver in a subset of ACC disease pathogenesis. Other notable molecular targets that have been studied include the cKIT receptor, the EGFR pathway, and NOTCH1, all with limited efficacy in clinical trials. The ongoing investigation of molecular abnormalities underpinning ACC that may be responsible for carcinogenesis is critical to identifying and developing novel targeted therapies.

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.

Immunophenotypical alterations with impact on the epithelial-mesenchymal transition (EMT) process in salivary gland adenoid cystic carcinomas

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary glands neoplasms with an indolent clinical course, slow-growing but locally aggressive and quite often with delayed recurrence and distant metastasis. In order to elucidate this tumoral behavior, we conducted an immunohistochemical study investigating the alterations of epithelial phenotype with anti-cytokeratin (CK) AE1/AE3 and anti-E-cadherin antibodies, and the acquisition of mesenchymal phenotype with vimentin, fibronectin, N-cadherin and P-cadherin in salivary ACCs. Thus, we recorded a reduction of CK AE1/AE3, E-cadherin, P-cadherin and fibronectin reactivity in the solid variant and especially in the cells from the periphery of invasive neoplastic proliferations, regardless histological type. These phenotypical alterations suggest the involvement of the epithelial–mesenchymal transition (EMT) process in the progression of salivary ACCs.

Apatinib in patients with recurrent or metastatic adenoid cystic carcinoma of the head and neck: a single-arm, phase II prospective study

Background

Apatinib, a vascular endothelial growth factor receptor (VEGFR) blocker, has demonstrated encouraging antitumor activities and tolerable toxicities in various cancer types. Recurrent or metastatic adenoid cystic carcinoma of the head and neck (R/MACCHN) carries a poor prognosis, and treatment options are currently limited. This study was conducted to explore the antitumor activity and safety of apatinib in patients with R/MACCHN.

Methods

In this phase II single-arm, prospective study, patients aged 15-75 years with incurable R/MACCHN received apatinib at a 500 mg dose once daily until intolerance or progression occurred. The primary endpoint was the 6-month progression-free survival (PFS) rate based on RECIST version 1.1. The secondary endpoints included response rate, overall survival (OS), and safety. Efficacy was assessed in all dosed patients with at least one post-baseline tumor assessment.

Results

Among 68 patients treated with apatinib, 65 were evaluable for efficacy analysis, with a median follow-up time of 25.8 months. The 6-month, 12-month, and 24-month PFS rates were 92.3% [95% confidence interval (CI): 83-97.5%], 75.2% (95% CI: 61.5-84.0%) and 44.7% (95% CI: 32.3-57.5%), respectively. The objective response rate (ORR) and disease control rate (DCR), as assessed by investigators, were 46.2% (95% CI: 33.7-59.0%) and 98.5% (95% CI: 91.7-100.0%), respectively. The median duration of response was 17.7 months [interquartile range (IQR) 14.0-20.9]. The 12-month and 24-month OS rates were 92.3% (95% CI: 83.0-97.5%) and 82.3% (95% CI: 70-90.4%), respectively. The most common adverse events of grades 3-4 were hypertension (5.9%), proteinuria (9.2%), and hemorrhage (5.9%). One patient developed a fatal hemorrhage.

Conclusion

An encouraging PFS, a high ORR, and a manageable safety profile were observed in this study. It seems that the administration of apatinib in R/MACCHN is likely to have a clinically meaningful therapeutic benefit and warrants further investigation.This study was prospectively registered in ClinicalTrials.gov (NCT02775370; date of registration: 17 May 2016; date of first patient enrollment: 25 May 2016).

Intensity modulated radiation therapy may improve survival for tracheal-bronchial adenoid cystic carcinoma: A retrospective study of 133 cases

PURPOSES

This study aimed to evaluate the role of radiotherapy (RT) and intensity modulated radiation therapy (IMRT) in adjuvant and definitive settings of tracheal-bronchial adenoid cystic carcinoma (TACC) treatment.

MATERIALS/METHODS

TACC patients (n = 133) treated with surgery and/or RT curatively in our institution between January 1^st, 1984 and December 31^st, 2017 were analyzed retrospectively.

RESULTS

Among the 116 patients undergoing surgery, 50 (43.1 %) achieved complete resections and 66 (56.9 %) had positive surgical margins. For patients with positive margins, overall adjuvant RT was correlated with no significantly improved OS (10-year: 58.0 % vs. 47.9 %; P =  0.340) and a slight LRFS benefit (5-year: 81.9 % vs.75.6 %; P =  0.056), but adjuvant IMRT showed significant superiority in both OS (10-year: 82.9 % vs. 47.9 %; P =  0.031) and LRFS (5-year: 100.0 % vs. 75.6 %; P =  0.001) in comparison with no postoperative RT. Multivariate analysis also identified adjuvant IMRT as a significant favorable factor with OS (HR = 0.186, 95 %CI: 0.039-0.883; P =  0.034). For 17 patients receiving definitive RT, IMRT achieved promising 5-year OS of 88.9 % and LRFS of 64.3 %, yet no significant difference from non-IMRT group was reached (P = 0.447 and 0.706). Different therapies presented no significantly different impact on DMFS, whilst DMFS explained more of the OS variances (P < 0.001, R² = 0.480) than LRFS (P < 0.001, R² = 0.323).

CONCLUSION

IMRT could confer greatly improved OS and LRFS in postoperative setting for TACC patients with positive surgical margins. IMRT was also a good therapeutic option for definitive TACC with promising survival and local control.

Primary Pituitary Adenoid Cystic Carcinoma: A Rare Salivary Gland-Like Tumor in the Sella

Adenoid cystic carcinoma (ACC) is a tumor of the exocrine glands that originates primarily from the minor and major salivary glands, nasopharynx, and lacrimal glands. ACC grows slowly but is locally aggressive and prone to recurrence. It is uncommon for ACCs to develop in the pituitary gland as a primary tumor. We present a case of primary pituitary ACC extending to the sphenoid sinus resembling an invasive adenoma in a 71-year-old woman with a history of nasal epistaxis. We reviewed other reported cases of pituitary ACCs with retrospective validation of whether the tumor was primary or not. The intrasellar tumor exhibited MYB rearrangement with enlargement and destruction of the sella turcica and dural tears toward the sphenoid sinus, which would be consistent for a tumor originating from the pituitary gland. Including our case, only four intrasellar and one suprasellar ACC have been confirmed as primary tumors. All intrasellar ACCs had the characteristic of some form of invasion of neighboring structures with evidence of hyperprolactinemia. ACC could develop in the pituitary gland as a form of salivary gland-like tumor derived from the ectopic salivary gland rests. ACCs rarely arise from the pituitary gland; however, the accurate determination of primary occurrence is difficult because of the invasive nature of these tumors, and the anatomical relationship with the sphenoid sinus and the cavernous sinus. Excessive bleeding from the tumor or unexpected internal carotid artery injury should be avoided during surgery for primary and secondary pituitary ACC.

Adenoid Cystic Carcinoma of Salivary Gland: A Ten-Year Single Institute Experience

Adenoid cystic carcinoma is a rare tumor, accounting for about 7.5% of all salivary gland neoplasms. More frequent developing in minor salivary gland, this is a slow-growing tumor with a long-lasting natural evolution, quite aggressive locally, but which has a tendency toward local recurrence and even for distant metastasis. We conducted a retrospective study limited to a period of 10 years in a single medical institution to investigate the morphoclinical profile of this tumor. Thus, we have established that about 60% of the tumors developed in men, with near 40% of the cases in patients in the sixth decade and, most common, the pathology affected the parotid and minor salivary glands from the hard palate mucosa. Histopathologically, prevailed the solid variant, with 72% cases presenting perineural invasion, and 41% cases showing positive surgical resection margins. Most cases had a long-standing asymptomatic evolution, so that at the time of diagnosis, more than two thirds of the patients were at least in stage II-pTNM, and in one-fifth of the cases histopathology showed lymph nodes disseminations.

Intraosseous adenoid cystic carcinoma of the mandible: A rare presentation

Central adenoid cystic carcinoma (ACC) of the mandible is a rare entity arising from minor salivary glands. Their clinical and radiographic features may be similar to any odontogenic/nonodontogenic pathology, thus making their precise diagnosis wearisome. ACC is well documented for its protracted clinical course, perineural invasion, multiple recurrence rates and its propensity for distant metastases. The aim of this study is to report a rare case of primary central ACC of the mandible with an unusual presentation in terms of location, however, demonstrating the classical features of ACC in histopathology and positivity in immunohistochemistry to S100, calponin and CD117. A thorough clinical, radiographic, CT evaluation and meticulous metastatic workup along with long-term follow-up is advised in such cases. Although central ACC is extremely rare, especially in the anterior mandible, it should be included in the differentials for lesions of the mandible.

Current aspects of salivary gland tumors - a systematic review of the literature

Objectives: This study provides an up-to-date overview of the distribution of salivary gland tumors in relation to sex, land of treatment, localization of the tumor in the mouths, and benign/malignant disease of this type of tumor. We hypothesized that the distribution of patients with salivary gland tumors could vary according to country, gender, age and tumor specificity. In addition there is a comparison of the primary classification of salivary gland tumors from 1981 and the recent classification from 2005.

Materialsand methods: Data from the Medline database PubMed.gov and supplementary sources were used to conduct a systematic literature search. For this purpose, data from different studies were independently collected using a previously designed questionnaire.

Results: The first section analyzes the general features of the relevant salivary gland tumors from 141 studies involving a total of 25,826 patients across 30 different countries in terms of gender and the occurrence of benign/malignant salivary gland tumors. These data were summarized and presented.

Conclusion: This review offers an insight into the dramatic local differences with regard to salivary gland tumor occurrence as a stepping stone to further classify such data in order to derive effective therapy options, prognosis and widen the general understanding of the subject.

Adenoid cystic carcinoma of the gastroesophageal junction: A case report

RATIONALE

Adenoid cystic carcinoma (ACC) rarely occurs in the digestive tract, particularly in the gastroesophageal junction.

PATIENT CONCERNS

A 44-year-old male vomiting blood was admitted to our hospital. Endoscopic ultrasound showed a 2.2 × 3.0 cm submucosal tumor in the gastroesophageal junction.

DIAGNOSIS

According to the histopathological examination, the tumor was composed predominantly of ductal epithelial and myoepithelial cells. Immunohistochemical staining revealed that the tumor expressed cytokeratin, cluster of differentiation 117, p63, and calponin. Based on these findings, ACC was diagnosed.

INTERVENTIONS

Endoscopic submucosal dissection (ESD) was performed to remove the tumor. As the margins of the ESD specimen were positive, the patient underwent total gastrectomy with D2 lymphadenectomy. Finally, neither residual tumor nor lymphatic metastasis was detected in the surgical specimens.

OUTCOMES

No sign of recurrence has been detected during 36 months of follow-up as of October 2018.

LESSONS

ESD may be an alternative treatment for cardial ACC invading the submucosa.

MYB-NFIB gene fusions identified in archival adenoid cystic carcinoma tissue employing NanoString analysis: an exploratory study

BACKGROUND

Adenoid cystic carcinoma (ACC) is a slow growing salivary gland malignancy that is molecularly characterized by t(6:9)(q22-23;p23-24) translocations which predominantly result in MYB-NFIB gene fusions in nearly half of tumours. Detection of MYB-NFIB transcripts is typically performed with fresh ACC tissue using conventional RT-PCR fragment analysis or FISH techniques, which are prone to failure when only archival formalin fixed paraffin embedded (FFPE) tissue is available. The purpose of this pilot study was to evaluate the utility of NanoString probe technology for the detection of MYB-NFIB transcripts in archival ACC tissue.

METHODS

A NanoString probeset panel was designed targeting the junctions of three currently annotated MYB-NFIB fusion genes as well as 5'/3' MYB probesets designed to detect MYB gene expression imbalance. RNA isolated from twenty-five archival ACC specimens was profiled and analyzed. RT-qPCR and sequencing were performed to confirm NanoString results. MYB protein expression was analyzed by immunohistochemistry.

RESULTS

Of the 25 samples analyzed, 11/25 (44%) expressed a high degree of MYB 5'/3' imbalance and five of these samples were positive for at least one specific MYB-NFIB variant in our panel. MYB-NFIB variant detection on NanoString analysis was confirmed by direct cDNA sequencing. No clinical correlations were found to be associated with MYB fusion status.

CONCLUSION

We conclude that the application of NanoString digital probe counting technology is well suited for the detection and quantification of MYB-NFIB fusion transcripts in archival ACC specimens.

MYB promotes the growth and metastasis of salivary adenoid cystic carcinoma

The incidence of recurrent t(6;9) translocation of the MYB proto-oncogene to NFIB (the gene that encodes nuclear factor 1 B-type) in adenoid cystic carcinoma (ACC) tumour tissues is high. However, MYB [the gene that encodes transcriptional activator Myb (MYB)] overexpression is more common, indicating that MYB serves a key role in ACC. The current study aimed to investigate the role of MYB in salivary (S)ACC growth and metastasis. A total of 50 fresh-frozen SACC tissues and 41 fresh-frozen normal submandibular gland (SMG) tissues were collected to measure MYB mRNA expression, and to analyse the associations between MYB and epithelial-mesenchymal transition (EMT) markers. Compared with normal SMG tissue, SACC tissues demonstrated significantly increased MYB expression, with a high expression rate of 90%. Interestingly, MYB tended to be negatively correlated with CDH1 [the gene that encodes cadherin-1 (E-cadherin)] and positively correlated with VIM (the gene that encodes vimentin), suggesting that MYB is associated with SACC metastasis. To explore the role of MYB in SACC, the authors stably overexpressed and knocked down MYB in SACC cells. The authors of the current study demonstrated that MYB overexpression promoted SACC cell proliferation, migration and invasion, whereas its knockdown inhibited these activities. Additionally, when MYB was overexpressed, CDH1 expression was downregulated, and CDH2 (the gene that encodes cadherin-2), VIM and ACTA2 (the gene that encodes actin, aortic smooth muscle) expression was upregulated. Then, the effect of MYB on lung tumour metastasis was investigated in vivo in non-obese diabetic/severe combined immunodeficiency mice. MYB overexpressing and control cells were injected into the mice through the tail vein. The results revealed that MYB promoted SACC lung metastasis. Collectively, these results demonstrated that MYB is aberrantly overexpressed in SACC tissues, and promotes SACC cell proliferation and metastasis, indicating that MYB may be a novel therapeutic target for SACC.

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.

Adenoid cystic carcinoma of the vagina: A case report

RATIONALE

Squamous carcinoma is the most common malignancy of vagina. Adenoid cystic carcinoma (ACC) in the vagina is very rare.

PATIENT CONCERNS

In the present study, we present a 45-year-old woman with a palpable swelling in the vagina. The patient reported body paresthesia, chest congestion, expiratory dyspnea, and itching in the thigh root.

DIAGNOSIS

The ultrasound results revealed inhomogeneous echoes of the muscular layer in the middle and distal of the vagina, and probed a slightly richer blood flow signal. Then biopsy was performed. On microscopic examination, it was observed that tumor cells were arranged in a tubular or cribriform pattern, and exhibited a consistent size, small nuclei, and nuclear fission. The myoepithelium was lined around the glandular cavity, but the myoepithelium was tumorous. Immunohistochemistry was performed for further verification. Vimentin was positive in mesenchyme and CK-P was positive in epithelial cells. P63 and calponin were spotted, which were focal positive around the glandular cavity. Finally, the patient was diagnosed as ACC.

INTERVENTIONS

At last, the patient chose chemoradiotherapy, not surgical excision.

OUTCOMES

The patient is alive and well 13 months after the initial diagnosis.

LESSONS

ACC in the vagina is extremely rare. To our knowledge, this report is the first case of ACC arising from the vagina in English-language literature. Extensive surgical section of the tumour and chemoradiotherapy are recommended for therapy. Because of rarity, the prognosis of ACC in vagina is not known.

A case of sublingual adenoid cystic carcinoma involving the mandible presenting as a "skip lesion"

Adenoid cystic carcinoma (ACC) is a slowly growing malignant neoplasm with a propensity for perineural invasion. Microscopic invasion of ACC often prevents its detection on computed tomography (CT) or magnetic resonance imaging (MRI). We herein report a rare case of sublingual ACC presenting as a "skip lesion" that rapidly infiltrated the mandible after tumor resection. A 64-year-old man presented to Okayama University Hospital with an 18-month history of swelling in the right floor of the mouth. Clinical examination displayed an ulcerated swollen mass in that region. An enhanced mass was detected in the right sublingual space on CT and MRI. Bone surface erosion was observed at the inferior border of the mandible, but continuity with the sublingual mass or mass around that lesion was not detected by imaging. Sublingual tumor resection and selective neck dissection were performed by the pull-through method. Histopathologically, the surgical margins were free of cancer cells, and the tumor was diagnosed as ACC. Continuity with the sublingual mass and mandibular bone was not detected intraoperatively. However, marked bone resorption was detected in the anterior mandible 3 months after the operation. Biopsy was performed, and the findings indicated the same histological type of sublingual ACC. This case suggests that a malignant tumor close to the jaw bone requires the clinician to consider the possibility of bone invasion and to observe a wide region surrounding the tumor using imaging examination.

Oropharyngeal adenoid cystic carcinoma invading the mandibular bone through the mandibular foramen

Adenoid cystic carcinoma (ACC) is a rare epithelial tumor of the head and neck region, and one of the most common malignant tumors of the salivary glands. ACC is a slow-growing tumor characterized by perineural invasion and often has a high-recurrence rate. We describe a case of oropharyngeal ACC invading the mandibular bone through the mandibular foramen that showed a rare pattern of origin and invasion. A 70-year-old woman complained of noise and pain around the right temporomandibular joint. Osteomyelitis was suspected on the initial imaging examinations, although the findings were slightly atypical. However, a mass was observed in the right oropharyngeal wall on subsequent imaging examinations, and mandibular bone invasion, rather than osteomyelitis, was additionally suspected. The mass in the right oropharyngeal wall and right mandible was surgically excised. On postoperative histopathological examination, the mass was finally diagnosed as ACC. As tumor cells were also observed around the inferior alveolar nerve, mandibular bone invasion through the mandibular foramen was suspected. An oropharyngeal ACC invading the mandibular bone through the mandibular foramen is extremely rare. The present case suggests that bone invasion should be considered carefully with several imaging examinations when a malignant tumor such as ACC is observed around the jaw bone.

Mutational landscape and clonal diversity of pulmonary adenoid cystic carcinoma

Pulmonary adenoid cystic carcinoma is a rare and indolent lung malignancy, characterized by a protracted but unpredictable growth behavior. Currently, the treatment of PACC relies on surgery and local radiotherapy. However, treatment options for advanced PACC patients are limited. A larger number of studies demonstrated that advanced PACC patients obtained limited benefit from chemotherapy. Moreover, only a few case reports revealed PACC patients were candidates for target therapy. Therefore, there is an urgent need to develop novel therapies. Due to its rareness, its mutational landscape remains largely elusive. In this study, we performed capture-based ultra-deep sequencing on multiregional surgical specimens obtained from 8 PACC patients using a panel consisting of 295 cancer-related genes. Our data revealed distinctive mutational spectrum of PACC, which differed from non-small cell lung cancer and adenoid cystic carcinomas originated from other anatomical sites. PACC, lacking mutations in a majority of non-small cell lung cancer driver genes, has frequent mutations in genes participating in chromatin remodeling and NOTCH signaling pathway. We also elucidated spatial intra-tumoral heterogeneity, which varied among cases. Most mutations in chromatin remodelers were subclonal. Collectively, our findings elucidated molecular signature associated with PACC and highlighted the potential for epigenetic therapy in this disease.

Adenoid cystic carcinoma of the hard palate presenting as ipsilateral sixth nerve palsy

Adenoid cystic carcinoma (ACC) is an uncommon malignant neoplasm composed of basaloid epithelial and myoepithelial cells. The palate is the most commonly involved intraoral site for ACC. Here, we document the case of an advanced ACC arising from the hard palate that presented with right-sided sixth nerve palsy in a 75-year-old male with no other systemic illnesses. ACC of the head and neck involving the cavernous sinus and presenting as isolated sixth nerve palsy is exceedingly rare. In the absence of vasculopathic or ischemic risk factors, regardless of the age of the patient; neuroimaging should be performed in cases of isolated nontraumatic sixth nerve palsy.

Effect of survivin downregulation by simvastatin on the growth and invasion of salivary adenoid cystic carcinoma

Simvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, is been used in the clinic due to its pleiotropic effects, such as breast cancer, prostate cancer, pancreatic cancer. Simvastatin has recently been demonstrated to serve a potential role in the prophylaxis and therapeutics of a number of human cancers. The majority of reports concerning simvastatin treatment in the majority of human cancers have demonstrated that survivin is significantly decreased as a result and has been implicated in tumorigenesis. However, only a limited number of studies have investigated the use of simvastatin for the treatment of salivary gland adenoid cystic carcinoma (SACC). Therefore, this agent is a candidate for further investigation. The aim of the present study was to investigate the effects of simvastatin on the proliferation, invasion and apoptosis of the human salivary adenoid cystic carcinoma cell line, SACC-83, as well as survivin expression in the cells. The Cell Counting kit-8 assay results revealed that simvastatin inhibited the proliferation of SACC-83 cells in a dose-dependent (10 to 50 µM) and time-dependent (24 to 48 h) manner when compared with the untreated cells. Flow cytometry analysis indicated that simvastatin increased the percentage of cells in early and late apoptosis. Invasion assays revealed that simvastatin treatment inhibited the invasiveness of SACC-83 cells in a dose-dependent manner. In addition, simvastatin downregulated survivin expression in SACC-83 cells. In conclusion, simvastatin significantly inhibited the proliferation and invasion of SACC-83 cells, induced apoptosis, and reduced the expression of survivin, which suggests that simvastatin may be a novel target for SACC therapy.

Prognostic significance of p53 immunohistochemical expression in adenoid cystic carcinoma of the salivary glands: a meta-analysis

Adenoid cystic carcinoma of salivary glands is a rare adenocarcinoma and has been placed in “high-risk” category as poor long-term prognosis. The purpose of this study was to investigate p53 protein expression in adenoid cystic carcinoma of salivary glands and its correlation with clinicopathological parameters and prognosis. Literatures were searched from PubMed, Embase, Cochrane Library and Web of Science, which investigated the relationships between p53 expression and pathological type, clinical stage, local recurrence, metastasis, nerve infiltration and overall survival. A total of 1,608 patients from 36 studies were included in the analysis. The results showed that p53-postive expression rate was 49% in adenoid cystic carcinoma of salivary glands (OR=10.34, 95%CI: 4.93-21.71, P < 0.0001). The p53-postive expression was closely related to tumor types (OR=0.30, 95%CI: 0.14-0.65, P < 0.0001). The tumor with solid histological subtype had a strong positive correlation with p53 expression. The combined analysis revealed that the p53-positive expression rate among patients in T1and T2 stage was 41.4%, compared to 53.2% among those in T3 and T4 stage. However, there was no significant correlation between tumor stage and p53 expression (OR=0.47, 95% CI: 0.17-1.29, P = 0.14). Besides, compared to patients with p53-negative expression, those with p53-positive expression had a greater chance of developing metastasis, local recurrence and nerve infiltration as well as poorer 5-year overall survival (P < 0.01). In conclusion, the p53 expression is related to the survival of adenoid cystic carcinoma of salivary glands. It can be considered as the auxiliary detection index in treatment and prognosis of adenoid cystic carcinoma of salivary glands.

Adenoid cystic carcinoma of head and neck: A retrospective clinical analysis of a single institution

Objective

In this study, patients with head and neck adenoid cystic carcinoma were investigated with respect to disease characteristics, treatments, and potentially prognostic variables.

Materials and Methods

Between January 1995 and December 2010, 29 patients with ACC of the head and neck treated at our institution were retrospectively reviewed.

Results

The 29 patients had a mean age of 54.7 years. Of the 29 patients, 4 (13.8%) underwent surgical resection only, 21 (72.4%) underwent surgery with radiotherapy, and 4 (13.8%) received postoperative chemoradiotherapy. Of 9 patients (31.0%) who experienced a recurrence within the follow-up period, 3 (10.3%) had local recurrence and 5 (17.2%) had distant metastasis; 1 (3.4%) patient had both local recurrence and distant metastatic spread.

Conclusion

ACC is a relatively rare tumor associated with long survival, even in metastatic settings. Despite aggressive therapy with surgery, radiotherapy, and chemo- therapy, a marked potential for local and distant recurrence still remains.

Personalized oncogenomic analysis of metastatic adenoid cystic carcinoma: using whole-genome sequencing to inform clinical decision-making

Metastatic adenoid cystic carcinomas (ACCs) can cause significant morbidity and mortality. Because of their slow growth and relative rarity, there is limited evidence for systemic therapy regimens. Recently, molecular profiling studies have begun to reveal the genetic landscape of these poorly understood cancers, and new treatment possibilities are beginning to emerge. The objective is to use whole-genome and transcriptome sequencing and analysis to better understand the genetic alterations underlying the pathology of metastatic and rare ACCs and determine potentially actionable therapeutic targets. We report five cases of metastatic ACC, not originating in the salivary glands, in patients enrolled in the Personalized Oncogenomics (POG) Program at the BC Cancer Agency. Genomic workup included whole-genome and transcriptome sequencing, detailed analysis of tumor alterations, and integration with existing knowledge of drug-target combinations to identify potential therapeutic targets. Analysis reveals low mutational burden in these five ACC cases, and mutation signatures that are commonly observed in multiple cancer types. Notably, the only recurrent structural aberration identified was the well-described MYB-NFIB fusion that was present in four of five cases, and one case exhibited a closely related MYBL1-NFIB fusion. Recurrent mutations were also identified in BAP1 and BCOR, with additional mutations in individual samples affecting NOTCH1 and the epigenetic regulators ARID2, SMARCA2, and SMARCB1. Copy changes were rare, and they included amplification of MYC and homozygous loss of CDKN2A in individual samples. Genomic analysis revealed therapeutic targets in all five cases and served to inform a therapeutic choice in three of the cases to date.

Resection of Adenoid Cystic Carcinoma Originating From the Cavernous Sinus Via Endoscopic Endonasal Approach

A 50-year-old woman presented with gradually increasing right-sided facial numbness. Neuroimaging revealed a lesion in the right cavernous sinus mimicking meningioma. The resection of the right cavernous sinus neoplasm was implemented via endoscopic endonasal approach under general anesthesia. Histological examination of the surgical specimen revealed adenoid cystic carcinoma. Adenoid cystic carcinoma in the cavernous sinus is extremely rare as a primary lesion and challenging to manage. Little data exist to guide treatment when this tumor extends to involve the structure of cavernous sinus. Our study illustrates that endoscopic endonasal approach is a good choice for resection of the tumor in the cavernous sinus.

Expression of PIM-1 in salivary gland adenoid cystic carcinoma: Association with tumor progression and patients' prognosis

Pim-1 proto-oncogene, serine/threonine kinase (PIM-1) phosphorylates a series of substrates to exert its oncogenic function in numerous malignancies. The present study investigated the clinical significance of the PIM-1 protein, apoptosis status and apoptosis-associated proteins, including forkhead box O3a (FOXO3a), B cell lymphoma-2 (BCL-2) and BCL-2-associted agonist of cell death (BAD), were investigated in salivary gland adenoid cystic carcinoma (ACC) tissues. PIM-1 expression levels in 4 pairs of ACC tissues and corresponding normal salivary gland tissues were determined by western blot analysis. PIM-1, FOXO3a, BAD and BCL-2 expression levels in 60 ACC tissues were evaluated by immunohistochemistry (IHC). A terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assay was performed to detect the apoptosis status of ACC tissues. PIM-1 was revealed to be highly expressed in ACC tissues compared with adjacent normal tissues. IHC staining results demonstrated high expression ratios of PIM-1, FOXO3a, BCL-2 and BAD [33.33% (20/60), 51.67% (31/60), 51.67% (31/60) and 55% (33/60)], respectively, and significant correlations between the expression of PIM-1 and FOXO3a and BCL-2 (P<0.05). Apoptotic rates were significantly associated with PIM-1, FOXO3a, BCL-2 and BAD expression levels (P<0.05). PIM-1 expression levels were significantly associated with tumor size, lymph node involvement, nerve invasion, distant metastasis and weakly associated with tumor node metastasis stage. Kaplan-Meier survival curves revealed that PIM-1 expression level was significantly associated with disease-free survival of patients with ACC (P=0.009). Cox regression multivariate analysis results revealed that histotype, distant metastasis and apoptotic rate were independent prognosis factors for ACC. Assessment of PIM-1 may be useful in investigating the malignant behaviors of ACC and predicting the outcome of patients with ACC.

Clinical significance of post-surgical residual tumor burden and radiation therapy in treating patients with lacrimal adenoid cystic carcinoma

Retrospective analyses were done on 19 lacrimal adenoid cystic carcinoma (ACC) patients who underwent curative treatment between 1997 and 2013. Nine patients (47.4%) had T1-2 disease and ten (52.6%) had T4 disease. Surgical procedures were globe-preserving tumor resection in 11 patients (57.9%), incisional biopsy in five (26.3%), and orbital exenteration was undertaken in three (15.8%). Residual tumor burdens were R0/1 in 12 patients (63.2%) and R2 in seven (36.8%). Radiation therapy (RT) was recommended to all patients, and 16 (84.2%) completed RT (median 60 Gy). After median follow-up of 57.5 months, seven (36.8%) developed progression and three (15.8%) died. Local recurrence occurred in four patients (21.1%), distant metastasis in one (5.3%), and combined local recurrence and distant metastasis in two (10.5%). Progression-free survival and overall survival rates at 5-years were 64.5% and 82.6%, respectively. Among 12 patients following R0/1 resection, two (16.7%) developed local recurrence and none died, while among seven following R2 resection, five (71.4%) developed progression and three (42.9%) died. RT following R0/R1 resection could reduce progression. Globe-preserving surgery and RT seemed optimal strategy for T1-2 disease. Careful attention should to be paid to minimize residual tumor burden at surgery and effort for safe radiation dose escalation would be desired.

Adenoid Cystic Carcinoma Metastasized to Colon

Adenoid cystic carcinoma (ACC) is an infrequent cause of malignancy that accounts for 1% of all tumors of the oral and maxillofacial region. We present a 59-year-old woman with a past medical history of adenoid cystic carcinoma of the left salivary gland treated with radiation and thoracotomy due to lung metastasis. Years after the onset of diagnosis, she presented with nonspecific gastrointestinal symptoms. For this reason, an abdominal computed tomography (CT) scan was done, revealing a liver mass in the right lobe, involving segments eight and five, concerning for malignancy. A colonoscopy was indicated for screening purposes, showing a large polyp that was biopsied. A histopathologic examination of the colon polyp and a liver biopsy was compatible with ACC metastatic carcinoma. We report this case to highlight an unusual location of metastatic ACC. Furthermore, there is no case report in the literature where colon metastasis has been described.

Aggressive Adenoid Cystic Carcinoma of Maxillary Sinus in a 43-Year-Old Male: Rare Case Report and Review of Literature

Adenoid cystic carcinoma (ACC) is a rare malignant tumor, mostly involving the minor salivary glands. Herein, we present a case of ACC in a 43-year-old man with symptoms of dental abscess as the initial presentation of the tumor. In spiral computed tomography (CT) scan, soft tissue mass with the erosion of maxillary sinus wall on the right side of the alveolar ridge was evident. Histopathological examination of the excised tumor with immunohistochemical studies (C-kit, Vimentin, pan-cytokeratin, p53, p63, and ki67 positive reaction) confirmed grade 2 ACC in the maxillary sinus. The patient underwent hemimaxillectomy and right-neck dissection. Due to the extension of tumor cells excessively into the surrounding tissues and involvement of orbital bone, complete and total resection of the tumor with safe margins could not be done. After surgery, adjuvant radiotherapy was considered for the patient. At the end of treatment, the patient lost his eye vision. Seventeen months from initial diagnosis, he was still alive without lung or distant metastasis.

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.

Model to Predict Cause-Specific Mortality in Patients with Head and Neck Adenoid Cystic Carcinoma: A Competing Risk Analysis

PURPOSE

The main objective of this study was to evaluate the cumulative incidence of cause-specific death and other causes of death for patients with head and neck adenoid cystic carcinoma (ACC). The secondary aim was to model the probability of cause-specific death and build a competing risk nomogram to predict cause-specific mortality for this disease.

METHODS

Data were extracted from the US National Cancer Institute's Surveillance Epidemiology, and End Results (SEER)-18 dataset. The study cohort included patients with a diagnosis of primary head and neck ACC during the period 2004-2013. We calculated the cumulative incidence function (CIF) for cause-specific death and other causes of death, and constructed the Fine and Gray's proportional subdistribution hazard model, as well as a competing-risk nomogram based on Fine and Gray's model, to predict the probability of cause-specific death for patients with head and neck ACC.

RESULTS

After data selection, 1435 cases were included for analysis. Five-year cumulative incidence of cause-specific death was 17.4% (95% confidence interval [CI] 15.1-19.8%) and cumulative incidence of other causes of death was 5.8% (95% CI 4.4-7.4%). Predictors of cause-specific death for head and neck ACC included age, tumor size, advanced T stage, positive lymph node, distant metastasis, and surgery. The nomogram was well-calibrated, and had good discriminative ability.

CONCLUSION

The large sample allowed us to construct a reliable predictive model for rare malignancy. The model performance was good, with a concordance index of 0.79, and the nomogram can provide useful individualized predictive information for patients with head and neck ACC.

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.

Adding concurrent chemotherapy to postoperative radiotherapy improves locoregional control but Not overall survival in patients with salivary gland adenoid cystic carcinoma-a propensity score matched study

PURPOSE

To compare the long-term outcomes in patients with salivary gland adenoid cystic carcinoma (SGACC) treated with post-operative chemoradiotherapy (POCRT) versus post-operative radiotherapy (PORT).

METHODS

We retrospectively reviewed the records of 91 SGACC patients treated with surgery followed by PORT (n = 58) or POCRT (n = 33) between 2000 and 2013. Treatment outcomes between groups were compared using propensity score matching (1:1 nearest neighbor).

RESULTS

The median radiation dose was 66 Gy, and patients were followed up for a median of 71 months. Cisplatin-based concurrent regimens were the most commonly used chemotherapy schedules. In the entire study cohort, patients undergoing POCRT showed a trend toward higher locoregional control (LRC) rates than those treated with PORT alone at both 5 and 8 years (97 and 97 % versus 84 and 79 %, respectively; P = .066). Distant metastases were the most common form of treatment failure and occurred in 31 (34 %) patients (PORT, n = 17; POCRT, n = 14). After propensity score matching (33 pairs), patients receiving POCRT had 5- and 8 year LRC rates of 97 and 97 %, respectively, compared with 79 and 67 % for patients treated with PORT alone (P = .017). The two groups did not differ significantly in terms of distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS). However, a significantly better opioid-requiring pain-free survival (ORPFS) was achieved in POCRT group (P = .038). Subgroup analyses revealed that patients with stage III - IV disease (P = .040 and .017), positive surgical margins (P = .011 and .050), or perineural invasion (P = .013 and .035) had significantly higher 5- and 8 year LRC and ORPFS when treated with POCRT, respectively.

CONCLUSIONS

In SGACC patients, adding concurrent chemotherapy to PORT may increase LRC and ORPFS rates, particularly in presence of stage III - IV disease, positive surgical margins, or perineural invasion. However, no significant differences in DMFS, DFS, and OS were observed.