Adenoid cystic carcinoma of the minor salivary glands: a retrospective series of 29 cases and review of the literature

Establishment and characterization of cMYB-expressing human salivary adenoid cystic carcinoma cell lines (UM-HACC-14, UM-HACC-6) and matching patient-derived xenograft model (UM-PDX-HACC-14)

OBJECTIVE

Limited availability of authentic human adenoid cystic carcinoma (ACC) cell lines has hindered progress in understanding mechanisms underpinning the biology of this disease and the development of safe and effective therapies.

STUDY DESIGN

Surgical human ACC specimens (UM-HACC-6, UM-HACC-14) were dissociated into single cell suspensions and cultured in fibronectin-coated flasks. Alternatively, tumor fragments were transplanted subcutaneously into female immunodeficient (SCID) mice to establish patient-derived xenograft tumors (PDX; UM-PDX-HACC-14).

RESULTS

Both ACC cell lines showed continuous growth in monolayers for over 100 passages. Total RNA-Seq, RT-PCR, and FISH analysis revealed that both are MYB-NFIB fusion negative. Western blots revealed passage-dependent expression of E-Cadherin, PCNA, p63, phospho-c-MYB, and NFIB. Both, UM-HACC-14 and UM-HACC-6 cells exhibited tumorigenic potential when injected orthotopically into mouse submandibular glands.

CONCLUSION

UM-HACC-14, patient-matching UM-PDX-HACC-14, and the UM-HACC-6 cell line are new, authenticated preclinical models of ACC that are well suited for mechanistic and developmental therapeutics studies.

Clinical Prediction Nomograms to Assess Overall Survival and Disease-Specific Survival of Patients with Salivary Gland Adenoid Cystic Carcinoma

Aim

Salivary gland adenoid cystic carcinoma (SACC) is the second highest incidence of malignant salivary gland tumor. The purpose of this study was to establish nomograms combined with SACC patients based on the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Patients with SACC were included in the SEER∗Stat Database from 2004 to 2016. The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was applied to filter potential prognostic clinical variables. Multivariate analysis from the Cox proportional hazards model was performed to determine the independent prognostic factors on overall survival (OS) and disease-specific survival (DSS), applied to develop nomograms. The Schönfeld residual test verified the proportional hazard assumption. The discrimination and consistency of nomograms was assessed and validated according to concordance index (C-index), receiver operating characteristic (ROC) curves, and calibration curves using an internal 1,000 times bootstrap resampling. The nomogram's net clinical benefit was assessed through decision curve analysis (DCA).

Results

A total of 658 patients with SACC were included. Age, T stage, N stage, M stage, histologic grade, and surgery were independent prognostic factors for OS and DSS. Based on these independent prognostic factors, nomograms were developed to predict 3-, 5-, and 10-year OS and DSS. In the validation of 1,000 times bootstrap resampling, the C-index and ROC curves had good discriminatory ability. The calibration curves indicated excellent consistency between the predicted and actual survival results in the nomograms. The DCA curves demonstrated that the nomograms had good clinical benefit and were superior to the TNM stage and other variables.

Conclusions

Two nomograms developed in this study precisely predicted the 3-, 5-, and 10-year OS and DSS rates of patients with SACC in accordance with independent prognostic factors, and their clinical value is better than TNM staging, providing a prognostic reference for other SACC patients.

PET-CT in Clinical Adult Oncology-V. Head and Neck and Neuro Oncology

Simple Summary

Positron emission tomography (PET), typically combined with computed tomography (CT) has become a critical advanced imaging technique in oncology. With PET-CT, a radioactive molecule (radiotracer) is injected in the bloodstream and localizes to sites of tumor because of specific cellular features of the tumor that accumulate the targeting radiotracer. The CT scan, performed at the same time, provides information to facilitate attenuation correction, so that radioactivity from deep or dense structures can be better visualized, but with head and neck malignancies it is critical to provide correlating detailed anatomic imaging. PET-CT has a variety of applications in oncology, including staging, therapeutic response assessment, restaging, and surveillance. This series of six review articles provides an overview of the value, applications, and imaging and interpretive strategies of PET-CT in the more common adult malignancies. The fifth report in this series provides a review of PET-CT imaging in head and neck and neuro oncology.

Abstract

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging, and longitudinal surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, and the potential pitfalls and nuances that characterize these applications. In addition, key tumor-specific clinical information and representative PET-CT images are provided to outline the role that PET-CT plays in the management of oncology patients. Hundreds of different types of tumors exist, both pediatric and adult. A discussion of the role of FDG PET for all of these is beyond the scope of this review. Rather, this series of articles focuses on the most common adult malignancies that may be encountered in clinical practice. It also focuses on FDA-approved and clinically available radiopharmaceuticals, rather than research tracers or those requiring a local cyclotron. The fifth review article in this series focuses on PET-CT imaging in head and neck tumors, as well as brain tumors. Common normal variants, key anatomic features, and benign mimics of these tumors are reviewed. The goal of this review article is to provide the imaging professional with guidance in the interpretation of PET-CT for the more common head and neck malignancies and neuro oncology, and to inform the referring providers so that they can have realistic expectations of the value and limitations of PET-CT for the specific type of tumor being addressed.

The Potential Prognostic Value of a Novel Hematologic Marker Fibrinogen-to-Lymphocyte Ratio in Head and Neck Adenoid-Cystic Carcinoma

Many patients with adenoid-cystic carcinoma (ACC) experience an indolent course of disease over many years but face late recurrence, and long-term survivors are rare. Due to its infrequent occurrence, it is hard to predict outcome in these patients. The fibrinogen-to-lymphocyte ratio (FLR) was recently proposed as an outcome prognosticator in different cancer entities. We aimed to investigate its prognostic relevance in patients with head and neck ACC. This retrospective analysis was performed including all patients treated for ACC between 1998 and 2020. The FLR ratio was calculated based on pretreatment values (0-7 days). The study cohort was dichotomized based on optimized threshold value and compared for differences in outcome (overall survival (OS) and disease-free survival (DFS)). In the cohort of 39 included patients, the OS was significantly longer in the low (n = 28) compared to the high pretreatment FLR group (n = 11) (median OS 150.5 months, 95% confidence intervals (CI) 85.3-215.7 months vs. 29.4 months, 95% CI not reached; p = 0.0093). Similarly, the DFS was significantly longer in the low FLR group (median DFS 74.5 months, 95% CI 30.6-118.4 months vs. 11.0 months, 95% CI 5.1-16.9 months; p = 0.019). The FLR is an easily obtainable and simple marker and may be a valuable outcome prognosticator in patients with ACC. Further studies are needed for validation of our results.

Magnetic resonance imaging of salivary gland tumours: Key findings for imaging characterisation

Salivary gland tumours are rare, representing only 3% of all head and neck neoplasms, with the parotid gland being the most common site (80 %). The risk of malignancy is inversely proportional to the size of the gland: lesions arising in the sublingual or minor salivary glands are more likely to be malignant, whereas parotid gland neoplasms are mostly benign. Fine needle aspiration cytology and core needle biopsy are considered the most accurate modalities for the diagnosis of a salivary gland neoplasm; however, they are not always conclusive due to procedural sampling errors and for the presence of a cytological / histological overlap between benign and malignant tumours. Moreover, they cannot be easily performed for parotid deep portion localisation. The role of magnetic resonance imaging (MRI) is growing and advanced techniques (diffusion-weighted and dynamic contrast-enhanced perfusion-weighted imaging) can provide useful additional information for the assessment of salivary gland neoplasms. The aim of this review is to present the main MRI and clinical features of salivary gland tumours to improve their comprehensive evaluation and characterisation.

Analysis of the clinicopathological characteristics and prognosis of adenoid cystic carcinoma of the intraoral minor salivary glands: a retrospective study of 40 cases

The clinicopathological aspects and prognostic factors of 40 patients with adenoid cystic carcinoma (ACC) of the intraoral minor salivary glands, treated between 2007 and 2017 at a single institution, were evaluated retrospectively. Twenty-six were female and 14 were male, and they ranged in age from 26 to 81 years (median 55 years). ACC occurred mainly in the palate, with 54.8% of cases presenting T3-T4 lesions. Curative surgery was performed in all patients, and 62.5% of patients were treated with postoperative adjuvant radiotherapy. In the final analysis, positive surgical margins were noted in 57.5% of cases and perineural invasion in 70%. Follow-up was at least 13 months (range 13-141 months, median 59 months). Nineteen patients (47.5%) developed recurrent disease after initial surgery and nine patients had died at the end of follow-up. The 5- and 10-year overall survival rates were 88.3% and 25.6%, respectively. The 5- and 10-year disease-free survival rates were 75.6% and 34.0%, respectively. Patients with a tumour size >4cm and those with positive surgical margins showed a significantly higher risk of local recurrence. Elective neck dissection is suggested for patients with clinically positive lymph nodes or a locally advanced tumour, especially those undergoing microvascular reconstruction. The survival analysis results are similar to those reported previously in the literature.

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.

Role of apoptotic, autophagic and senescence pathways in minor salivary gland adenoid cystic carcinoma

Background

Adenoid cystic carcinoma (ACC) is a salivary gland malignancy with poor long-term survival, which warrants studies aimed at clarifying the pathogenesis of this disease in order to widen the scope of therapeutic options currently available. Alterations in regulatory mechanisms relating to vascular support, cell death and autophagy are important pathways for tumor growth in cancer. Thus, the present study aimed to access vascular supply, apoptosis, autophagy and cell senescence in ACC of minor salivary glands.

Methods

We analyzed 25 cases of minor salivary gland ACC by immunohistochemistry using anti-CD34, anti-CD105, anti-D2–40, anti-Bax, anti-Bcl-2, anti-Beclin-1, anti-LC3B, anti-p21 and anti-p16.

Results

Microvessel density was low and based on anti-CD34, anti-CD105 and anti-D2–40 immunostaining. There was positivity for anti-CD34, anti-Bcl-2, anti-Beclin, anti-LC3B and anti-p21 and a positive correlation between Bcl-2 and Beclin (p = 0.014).

Conclusions

Our results showed that ACC does not depend on neo-angiogenesis and is probably associated to anti-apoptotic, autophagic and anti-senescence events.

Computed tomographic features of adenoid cystic carcinoma in the palate

Background

To evaluate the computed tomographic features and create a prediction model for clinical diagnosis of adenoid cystic carcinoma (ACC) in the palate with intact mucosa.

Methods

From March 2016 to May 2018, 102 patients with palatal tumors and intact mucosa, including 28 patients with a pathological diagnosis of ACC after surgery, were enrolled in this study. The patients’ clinical symptoms, computed tomographic features and pathological diagnoses were recorded and analyzed. Independent predictors of ACC were determined by using univariate analysis and multivariate logistic regression, and the discrimination and calibration of the prediction model was evaluated, and internal validation was performed.

Results

Univariate analysis of patients showed that ACC patients were more likely than non-ACC patients to be older (P = 0.019); to have palatine bone destruction (P<0.001) and greater palatine foramen (GPF) enlargement (P<0.001); to have involvement of the pterygopalatine fossa (P<0.001), foramen rotundum (P<0.001), nasal cavity (P<0.001) and maxillary bone (P<0.001); and to have numbness (P = 0.007) and pain (P<0.001). Multivariate logistic analysis showed that age and GPF enlargement were independent predictors of ACC in palatal tumors. The diagnostic prediction model showed good discrimination and calibration, as evaluated by the area under the receiver operating characteristic curve (0.98) and the Hosmer-Lemeshow goodness-of-fit test (P = 0.927).

Conclusions

The palate ACC prediction model based on age and GPF enlargement shows excellent discrimination with no evidence of poor calibration. Older patients with palatal tumors and intact mucosa should be considered for ACC when they have GPF enlargement.

Electronic supplementary material

The online version of this article (10.1186/s40644-019-0190-z) contains supplementary material, which is available to authorized users.

UM-HACC-2A: MYB-NFIB fusion-positive human adenoid cystic carcinoma cell line

OBJECTIVES

Limited availability of validated human adenoid cystic carcinoma (ACC) cell lines has hindered the mechanistic understanding of the pathobiology of this malignancy and the development of effective therapies. The purpose of this work was to generate and characterize a human ACC cell line.

MATERIAL AND METHODS

Immediately after surgery, a tumor fragment from a minor salivary gland from the tongue of a female Caucasian was minced, dissociated, and a single cell suspension was plated in fibronectin-coated flasks. A culture medium containing bovine brain extract and rhEGF was optimized for these cells. Whole exome sequencing was used to evaluate the presence of MYB-NFIB translocation.

RESULTS

The University of Michigan-Human Adenoid Cystic Carcinoma (UM-HACC)-2A cells showed continuous growth in monolayers for at least 180 in vitro passages while maintaining epithelial morphology. Short-tandem repeat (STR) profiling confirmed a 100% match to patient DNA. Whole exome sequencing revealed the presence of the MYB-NFIB fusion in UM-HACC-2A cells, which was confirmed by PCR analysis. Western blots revealed high expression of epithelial markers (e.g. E-cadherin, EGFR, pan-cytokeratin) and proteins associated with ACC (e.g. c-Myb, p63). Developmental therapeutic studies showed that UM-HACC-2A cells were resistant to cisplatin (IC₅₀ = 44.7 µM) while more responsive to paclitaxel (IC₅₀ = 0.0006 µM). In a pilot study, we observed that UM-HACC-2A cells survived orthotopic transplantation into the submandibular gland. Notably, one of the mice injected with UM-HACC-2A cells exhibited lung metastasis after 6 months.

CONCLUSION

UM-HACC-2A is a MYB-NFIB fusion-positive ACC cell line that is suitable for mechanistic and developmental therapeutics studies.

Early stage minor salivary gland adenoid cystic carcinoma has favourable prognosis

The purpose of the study was to evaluate the long-term outcome of minor salivary and mucous gland (MiSG) adenoid cystic carcinoma (ACC) of the head and neck and to compare the results with earlier reports including our recently published series on major salivary gland (MaSG) ACC. The study comprised 68 MiSG ACCs operated during 1974-2012 at the Helsinki University Hospital, Helsinki, Finland. Medical records and histological samples were reviewed. Our previously published cohort comprising 54 MaSG ACCs during the years from 1974 to 2009 was used for comparison. The most common locations were the oral cavity and sinonasal cavities. Most patients presented stages IV (33.8%) and I (23.5%) disease. Primary treatment with curative intent, mainly surgery, was offered for 64 patients. Thirty-three (51.6%) of these patients developed a disease recurrence and 22 (66.7%) patients in less than 5 years. The difference in the length of recurrence-free time (<5 vs. >5 years) had an impact on OS and DSS (p < 0.001) showing worse prognosis for the earlier recurring group. T classes 2-4 (p = 0.005, p < 0.001, and p = 0.001, respectively) and stages II-IV (p = 0.019, p < 0.001, and p = 0.002, respectively) were associated with worse OS, DSS, and DFS. MiSG ACC had a similar long-term survival compared to MaSG ACC. Patients with stage I MiSG ACC seem to carry a favourable prognosis compared with those with stages II, III, and IV tumours. It is thus noteworthy that stage II tumours represent a truly advanced disease entity warranting a more aggressive treatment approach.

Minor intraoral salivary gland tumors: a clinical-pathological study

Objective

To evaluate the clinical-pathological profile of patients with minor salivary gland neoplasms.

Methods

A retrospective study of specific cases diagnosed as benign and malignant tumors of the minor salivary glands was performed. The data were collected from medical records of patients seen at a hospital over a period of 15 years. The sample was made up of 37 cases. For the pathological study, slides containing 5μm thick sections stained with hematoxylin and eosin were used. The data were tabulated using descriptive statistics.

Results

Malignant neoplasms represented 70.3% of cases. The mucoepidermoid carcinoma was the most common neoplasm (45.9%), followed by pleomorphic adenoma (24.4%). Most patients were female (70.3%), aged between 71 and 80 years. The palate (67.6%) and the retromolar region (10.8%) were the most affected sites.

Conclusion

Mucoepidermoid carcinoma was the most common tumor in minor salivary glands. These tumors are more common in females aged over 40 years. The palate was the most common affected site.

Objetivo

Avaliar o perfil clínico-patológico de pacientes com neoplasias de glândula salivar menor.

Métodos

Foi realizado um estudo retrospectivo de casos específicos diagnosticados como neoplasias benignas ou malignas de glândula salivar menor. Os dados foram coletados dos prontuários dos pacientes atendidos em um hospital no período de 15 anos. A amostra final foi de 37 casos. Para o estudo histopatológico, foram usadas lâminas contendo secções com 5μm de espessura, coradas pela técnica de hematoxilina e eosina. Os dados foram tabulados de forma descritiva.

Resultados

As neoplasias malignas representaram 70,3% dos casos. O tipo histológico mais prevalente foi o carcinoma mucoepidermoide (45,9%), seguido do adenoma pleomórfico (24,4%). A maioria dos pacientes era do sexo feminino (70,3%), com idade entre 71 e 80 anos. O palato (67,6%) e a região retromolar (10,8%) foram os sítios mais acometidos.

Conclusão

O carcinoma mucoepidermoide foi o tumor mais comum das glândulas salivares menores. Estes tumores foram mais comuns em mulheres com mais de 40 anos. O palato foi o sítio mais acometido.