Expression Profiling of Extracellular Matrix Genes Reveals Global and Entity-Specific Characteristics in Adenoid Cystic, Mucoepidermoid and Salivary Duct Carcinomas

Simple Summary

The extracellular matrix (ECM), an important factor in tumour metastasis and therapy resistance, has not been studied in salivary gland carcinomas (SGC), so far. In this retrospective study, we profiled the RNA expression of 28 ECM-related genes in 11 adenoid cystic (AdCy), 14 mucoepidermoid (MuEp) and 9 salivary duct carcinomas (SaDu). Also, we validated our results in a multimodal approach. MuEp and SaDu shared a common gene signature involving an overexpression of COL11A1. In contrast, nonhierarchical clustering revealed a more specific gene expression pattern for AdCy, characterized by overexpression of COL27A1. In situ studies at RNA level indicated that in AdCy, ECM production results from tumour cells and not from cancer-associated fibroblasts as is the case in MuEp and SaDu. For the first time, we characterized the ECM composition in SGC and identified several differentially expressed genes, which are potential therapeutic targets.

Abstract

The composition of the extracellular matrix (ECM) plays a pivotal role in tumour initiation, metastasis and therapy resistance. Until now, the ECM composition of salivary gland carcinomas (SGC) has not been studied. We quantitatively analysed the mRNA of 28 ECM-related genes of 34 adenoid cystic (AdCy; n = 11), mucoepidermoid (MuEp; n = 14) and salivary duct carcinomas (SaDu; n = 9). An incremental overexpression of six collagens (including COL11A1) and four glycoproteins from MuEp and SaDu suggested a common ECM alteration. Conversely, AdCy and MuEp displayed a distinct overexpression of COL27A1 and LAMB3, respectively. Nonhierarchical clustering and principal component analysis revealed a more specific pattern for AdCy with low expression of the common gene signature. In situ studies at the RNA and protein level confirmed these results and indicated that, in contrast to MuEp and SaDu, ECM production in AdCy results from tumour cells and not from cancer-associated fibroblasts (CAFs). Our findings reveal different modes of ECM production leading to common and distinct RNA signatures in SGC. Of note, an overexpression of COL27A1, as in AdCy, has not been linked to any other neoplasm so far. Here, we contribute to the dissection of the ECM composition in SGC and identified a panel of deferentially expressed genes, which could be putative targets for SGC therapy and overcoming therapeutic resistance.

Trophoblast Cell Surface Antigen 2 (Trop-2) Protein is Highly Expressed in Salivary Gland Carcinomas and Represents a Potential Therapeutic Target

Treatment options for unresectable, recurrent or metastatic salivary gland carcinomas (SGC) are scarce. Trophoblast cell surface antigen 2 (Trop-2) is a transmembrane glycoprotein that is involved in a variety of oncogenic cell signaling pathways. Its potential as a target for the antibody-drug conjugate sacituzumab govitecan has already been demonstrated in different tumor entities. The United States Food and Drug Administration approved this antibody-drug conjugate for the treatment of metastatic triple-negative breast cancer. Here, we aimed to investigate Trop-2 protein expression in different entities of SGCs. We retrospectively reviewed the medical records of all patients that underwent surgery for a primary SGC in a tertiary referral center between 1990 and 2014. Immunohistochemical (IHC) staining for Trop-2 was performed and rated as negative, weak, moderate or high using a semiquantitative score. Additionally, representative cases were analyzed using MALDI-mass spectrometry (MS) imaging to confirm the IHC results. The cohort consisted of 114 tumors of the parotid gland (90.4%) and submandibular gland (9.6%). It mainly included mucoepidermoid, salivary duct and adenoid cystic carcinomas. In IHC samples, 44% showed high, 38% moderate and 10% weak expression rates of Trop-2. MALDI-MS imaging confirmed the presence of Trop-2 protein in 80% of the tested tumor samples. This is the first study to demonstrate that several types of SGC express Trop-2 with variable intensity. Since there are currently few systemic treatment options for advanced SGCs, Trop-2 represents a promising target for further clinical studies, for instance, with sacituzumab govitecan.

Incidence and clinical outcome of primary carcinomas of the major salivary glands: 10-year data from a population-based state cancer registry in Germany

PURPOSE

The aim of this project was to provide an overview of the epidemiology of primary salivary gland carcinomas (SGC) in terms of incidence, distribution of clinicopathological features and survival in one of the largest cancer registries in Europe.

METHODS

Data were collected from patients with SGC of the major salivary glands registered in the population-based state cancer registry (Landeskrebsregister LKR) in North Rhine-Westphalia (NRW), Germany from 01/01/2009 to 12/31/2018. Age standardization of incidence was performed and relative survival estimates were computed by sex, histological group, age group and T-, N-, and M-stage.

RESULTS

A total of 1680 patients were included in this analysis. The most frequent tumor localization was the parotid gland (78%). Adenocarcinoma (not otherwise specified) was the most common tumor entity (18.5%). Most tumors were found in stages T1-T3 (29% T1; 29% T2; 28% T3). The age-standardized incidence rate (ASR) for SGC was 0.65/100,000 and remained stable during the observation period. There was an age-dependent incidence increasing especially from the age 70 years and onwards. The overall 5-year relative survival (RS) for all patients with SGC was 69.2%. RS was 80-95.6% for T1-2 stage tumors, 60.3% for T3, 47.3% for T4 stage, 87.4% for N0 and 51.2% for N1-2, 74.4% for M0 and 44.9% for M1.

CONCLUSION

Age-standardized incidence for SGC has been stable for the observed 10-year period. Smaller tumors and those without lymph node or distant metastases had a better RS than more advanced tumors.

Misleading Morphologic and Phenotypic Features (Transdifferentiation) in Solitary Fibrous Tumor of the Head and Neck: Report of 3 Cases and Review of the Literature

Solitary fibrous tumor (SFT) is a rare fibroblastic neoplasm with potentially malignant behavior that may develop in any anatomic site and may involve the head and neck (H&N) region as well. Although typical SFT has a relatively characteristic morphology, its morphologic spectrum is extraordinarily broad and also includes rare cases with dedifferentiation or transdifferentiation which result in aberrant morphologic and/or immunohistochemical features. However, since virtually all cases are molecularly characterized by NAB2::STAT6 gene fusions, molecular genetic methods or STAT6 immunohistochemistry can be effectively used in confirming the diagnosis. Herein, we report 3 diagnostically challenging H&N SFT cases with an unusual morphology and/or phenotypes closely mimicking other well-known H&N entities. The tumors originated in the oral minor salivary glands, the base of the tongue, and sinonasal tract and closely resembled hyalinizing clear cell carcinoma of the salivary gland, adenocarcinoma not otherwise specified and biphenotypic sinonasal sarcoma, respectively. All cases were positive for cytokeratins, variably expressed S100 protein, showed diffuse nuclear STAT6 positivity, and harbored NAB2::STAT6 gene fusions.

Mutually Exclusive Expression of COL11A1 by CAFs and Tumour Cells in a Large panCancer and a Salivary Gland Carcinoma Cohort

Procollagen 11A1 (COL11A1) is a central component of the extracellular matrix in many carcinomas, which is considered to be mainly produced by cancer associated fibroblasts (CAFs). As COL11A1 expression correlates with adverse prognosis and is implicated in chemoresistance, it is a promising putative target. For the first time, we used RNA in-situ hybridization to systematically identify the cells that produce COL11A1 in the ten most prevalent carcinoma types, lymphomas (n = 275) and corresponding normal tissue (n = 55; panCancer cohort). Moreover, as most salivary gland carcinomas (SGC) display distinct stromal architectures, we also analysed 110 SGC. The corresponding protein formation of COL11A1 was determined by MALDI-TOF-MS-Imaging. We report that colon, breast and salivary duct carcinomas are highly infiltrated by COL11A1 positive CAFs (CAFs_COL11A1) and might thus be promising candidates for antidesmoplastic or COL11A1-targeted therapies. The amount of CAFs_COL11A1 correlated significantly with tumour grade, tumour stage and nodal spread in the panCancer cohort. Significant associations between CAFs_COL11A1 and vascular invasion, perineural spread and nodal spread were observed in the SGC cohort. Also, we discovered that tumour cells of intercalated duct derived SGC and CAFs produce COL11A1 in a mutually exclusive manner. Our findings represent a novel mode of extracellular matrix production in carcinomas and could be highly relevant in the future. Our findings elucidate the mode of COL11A1 expression in very different carcinoma types and may aid to categorise tumours in the setting of possible future COL11A1-related therapies.

Facial nerve paralysis caused by a T-cell lymphoma

Facial nerve paralysis due to the infiltration by a lymphoma is rare and the prognosis remains poor. If perineural spread and meningeosis are suspected, quick interdisciplinary diagnostic work-up is recommended. It should include magnetic resonance imaging, biopsy of the lesion, bone marrow biopsy, and lumbar puncture. Therapy should be initiated immediately.

The lncRNA MRPL20-AS1 is associated with severe OSAS and downregulated upon hypoxic injury of endothelial cells

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is the most common sleep disorder in humans. Although OSAS is clearly related to arterial hypertension, coronary artery disease, and heart failure, it remains unknown through which pathomechanisms OSAS influences cardiovascular health. Recent research has pinpointed long non-coding RNAs (lncRNA) as important molecular mediators of various cardiovascular pathologies. In this study, we have identified the lncRNA MRPL20-AS1 to be affected by OSAS in patients as well as by hypoxia in vitro.

METHODS AND RESULTS

A transcriptomic analysis was performed on peripheral blood from four patients with severe OSAS taken after one night of polygraphic assessment. We found that three lncRNAs were significantly dysregulated, of which MRPL20-AS1 was the most significant. In a larger cohort of 22 OSAS patients, MRPL20-AS1 was inversely correlated with the apnea-hypopnea index (AHI). This indicates that OSAS patients with higher AHI levels and therefore more severe OSAS had lower levels of MRPL20-AS1 in the blood. The results were recapitulated in vitro by subjecting endothelial cells to hypoxia. In these experiments, hypoxia led to a significant downregulation of MRPL20-AS1 in endothelial cells.

CONCLUSION

MRPL20-AS1 may serve as a useful tool to identify patients suffering from severe OSAS and further research should be done to evaluate the therapeutic potential of MRPL20-AS1 as a target to counteract the cardiovascular effects of OSAS.

Nectin-4 is frequently expressed in primary salivary gland cancer and corresponding lymph node metastases and represents an important treatment-related biomarker

Many locally advanced and metastatic salivary gland carcinomas (SGC) lack therapeutic targets. Enfortumab vedotin, an antibody-drug conjugate binding to Nectin-4, recently gained FDA approval for third-line urothelial carcinoma. Therefore, the aim of this study was to assess the expression of Nectin-4 in primary SGC and corresponding lymph node metastases and to correlate it with clinicopathological data. Immunohistochemical staining for Nectin-4 was performed for patients who had undergone surgery with curative intent for primary SGC of the parotid or submandibular gland in a tertiary referral center between 1990 and 2019. One hundred twenty-two primary SGC and twenty corresponding lymph node metastases were included. Nectin-4 was expressed in 80.3% of primary SGC with a mean Histo(H-)score of 61.2 and in 90.0% of lymph node metastases with a mean H-score of 75.6. A moderate or high Nectin-4 expression was found in 25.9% of salivary duct carcinomas (SaDu) and in 30.7% of adenoid cystic carcinomas (ACC). SaDu patients with a lower T-stage (p = 0.04), no loco-regional lymph node metastases (p = 0.049), no vascular invasion (p = 0.04), and no perineural spread (p = 0.03) showed a significantly higher mean Nectin-4 H-score. There was a statistical tendency towards a more favorable disease-free survival among SaDu patients with a higher Nectin-4 expression (p = 0.09). Nectin-4 is expressed in SGC and therefore represents a potential therapeutic target, especially in entities with a high rate of local recurrence and metastatic spread such as SaDu and ACC.

[Mucoepidermoidcarcinoma - Importance in molecular pathology]

Mucoepidermoid carcinoma is the most common primary salivary gland malignancy and its tumor grading has an important prognostic significance. The 5 year overall survival rate is significantly higher for low grade mucoepidermoid carcinomas than for intermediate grade and high grade mucoepidermoid carcinomas. The translocation of t(11;19)(q21;p13) with the resulting CRTC1-MAML2 transfusion appears to be of prognostic relevance in patients with mucoepidermoid carcinoma. The translocation is detectable in 38-82 % of all mucoepidermoid carcinomas. Study results have shown a significantly better prognosis for patients with fusion-positive mucoepidermoid carcinomas than fusion-negative mucoepidermoid carcinomas. The t(11;19)(q21;p13) translocation can be found more often in low and intermediate grade mucoepidermoid carcinomas than in high grade tumors of the same entity. Moreover, fusion positive mucoepidermoid carcinoma were found more frequently in younger patients, smaller tumors, lower tumor stages and less frequently lymph node and distant metastases. Up to now, the translocation has not been of therapeutic importance. In selected cases, the lack of t(11;19)(q21;p13) translocation might facilitate the decision towards further escalation of therapy. More studies will be necessary to evaluate the individual prognostic and therapeutic value of CRTC1-MAML2 transfusion.

Analysis of nocturnal, hypoxia-induced miRNAs in sleep apnea patients

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular risk. The underlying mechanisms are largely unclear. MicroRNAs (miRNAs) are RNAs circulating in the blood that can be released into the bloodstream during hypoxia. In the present study, we investigate if OSAS-induced hypoxia results in a release of miRNAs that may mediate OSAS-associated cardiovascular damage.

METHODS

Blood was sampled from 23 OSAS patients before and after a polygraphically monitored night. Total circulating RNA was isolated from the plasma and quantified using real-time qPCR. Using a Taqman miRNA array, the levels of 384 different miRNAs were compared between evening and morning after polysomnography. The most highly upregulated miRNA (miRNA-505) and four additionally upregulated miRNAs (miRNA-127, miRNA-133a, miRNA-145, and miRNA-181a) were then quantified in a bigger patient cohort individually.

RESULTS

Apnea/Hypopnea-Index (AHI) was evaluated and averaged at 26 per hour on nocturnal polygraphy. In an initial miRNA array, a total of 4 miRNAs were significantly regulated. A significant increase of miRNA-145 was observed in the larger patient cohort. No significant changes in concentration were detected for miRNA-127, miRNA-133a, miRNA-181a, and miRNA-505 in this larger cohort.

CONCLUSION

OSAS results in the nocturnal release of miRNAs into the bloodstream. Our collected data may indicate a hypoxia-induced release of miRNAs into the bloodstream of OSAS-patients. In vitro experiments are needed to confirm the secretion of these miRNAs under hypoxia and evaluate the effect on the cardio vasculature.

Analysis of the Quality of Parotidectomy Videos on YouTube Using the IVORY-Grading-System

OBJECTIVE

The aim of this study was to evaluate the quality and the educational content of YouTube videos showing parotidectomy.

METHODS

We searched for videos displaying parotidectomy on YouTube. To rate parotidectomy videos, we introduced the "Instructional Videos in Otorhinolaryngology by YO-IFOS (IVORY)-grading-system (GS)" derived from the IVORY Guidelines, which pose established consensus recommendations for the production of educational surgical videos in otolaryngology. The videos were rated using the IVORY-GS, and the total score was tested for statistical association with views, likes, likes/dislikes-ratio, age, and length of the videos for validation of the IVORY-GS.

RESULTS

Overall, 50 parotidectomy videos were identified. Sixty-eight (68%) of the videos showed a superficial parotidectomy. The mean IVORY-GS total score was 24.9 (out of a maximum of 44 points). Video education quality was rated as moderate in 22% and high in 4%. There was a statistically significant correlation between the total score and the number of views (p = 0.03), the total score and the number of likes (p < 0.01), and the total score and the likes/dislikes ratio (p < 0.01). A higher total score was a significant predictor of more likes (p = 0.01) and a higher likes/dislikes ratio (p < 0.01).

CONCLUSION

Our modification of the IVORY Guidelines is otolaryngology-specific, suitable, and recommended to evaluate parotidectomy videos. To date, most videos are of poor educational quality. Future efforts in otolaryngology surgical video education could focus on the establishment of an online video platform.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2631-2637, 2023.

CD138 Is Expressed in Different Entities of Salivary Gland Cancer and Their Lymph Node Metastases and Therefore Represents a Potential Therapeutic Target

Advanced salivary gland carcinomas (SGC) often lack therapeutic options. Agents targeting CD138 have recently shown promising results in clinical trials for multiple myeloma and a preclinical trial for triple-negative breast cancer. Immunohistochemistry for CD138 was performed for all patients who had undergone primary surgery for SGC with curative intent. Findings were validated using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) imaging. Overall, 111 primary SGC and 13 lymph node metastases from salivary duct carcinomas (SaDu) were evaluated. CD138 expression was found in 60% of all SGC with differing expression across entities (p < 0.01). A mean of 25.2% of the tumor cells in mucoepidermoid carcinoma (MuEp) were positive, followed by epithelial-myoepithelial carcinoma (20.9%), acinic cell carcinoma (16.0%), and SaDu (15.2%). High-/intermediate-grade MuEp showed CD138 expression in a mean of 34.8% of tumor cells. For SaDu, lymph node metastases showed CD138 expression in a mean of 31.2% of tumor cells which correlated with CD138 expression in their primaries (p = 0.01; Spearman’s ρ = 0.71). MALDI-MS imaging confirmed the presence of the CD138 protein in SGC. No significant association was found between clinicopathological data, including progression-free survival (p = 0.50) and CD138 expression. CD138 is expressed in the cell membrane of different entities of SGC and SaDu lymph node metastases and therefore represents a potential target for CD138 targeting drugs.

Round window accessibility during cochlear implantation

OBJECTIVE

To assess data regarding round window (RW) visibility and surgical approaches in cochlear implant cases, and to describe and analyze surgical steps relevant for the RW approach in cochlear implantation.

STUDY DESIGN

Prospective clinical study.

METHODS

A questionnaire was completed by surgeons after each of altogether 110 cochlear implantations. Round window membrane (RWM) visibility was graded according to the St Thomas Hospital (STH) classification.

RESULTS

Performing different surgical steps during the preparation of the RW niche, the RWM could be fully exposed (STH Type I) in 87%. A RW approach could be used for electrode insertion in 89% of the adult and 78% of the pediatric cases. The distribution of RW types differed significantly between adults and children. Drilling of the superior bony lip was the surgical step most frequently needed in adult as well as pediatric cases to obtain optimal RW exposure.

CONCLUSION

In children, optimized surgical exposure of the RW niche resulted in only 52% full RWM visibility; whereas in adults, this could be achieved in 87%. The facial nerve (FN) had to be exposed at the level of the posterior tympanotomy in more than 70% of pediatric cases with full RWM visibility; while in adult cases with 100% visibility, such specific exposure was necessary in only 33%. Thus, surgical preparation of the RW niche seems to be more demanding in children than in adults.

[Novel therapeutic approaches for salivary gland carcinomas]

Novel therapeutic options for the treatment of salivary gland malignancies have emerged due to the improvement and distribution of molecular pathological testing methods and the availability of targeted therapies. Since they are less toxic, these new agents are a valuable alternative to conventional cytotoxic chemotherapy. On the one hand, there are new entity-specific therapies such as NTRK inhibitor therapy for secretory carcinomas and axitinib therapy for adenoid cystic carcinomas. Moreover, cross-entity therapeutics such as antiandrogenic therapy, HER2 inhibition, and PI3K inhibition are also coming to the fore. For metastatic/recurrent salivary gland carcinomas that cannot be treated with targeted therapy, platinum-based chemotherapies continue to be therapy of choice.

Bi-institutional analysis of microbiological spectrum and therapeutic management of parotid abscesses

BACKGROUND

A parotid abscess (PA) is a complication of an acute bacterial parotitis with a potentially life-threatening course. To date, data on the diagnosis and therapy of PA is sparse and mostly consists of case reports or case series. Therefore, this study aimed at comprehensively analyzing the microbiological spectrum and the therapeutic management in a bi-institutional setting.

METHODS

A retrospective clinical chart review was performed to identify all patients surgically treated for PA at two tertiary care centers in Germany. Data on demographics, clinical management and microbiological data including species identification, pathogenicity, type of antibiotic therapy, adjustment of antibiotics, antibiotic sensitivity testing, and smear test results were extracted. Intervention-related variables and etiology were analyzed for their statistical association with outcome variables.

RESULTS

Overall, 85 patients were included. Most patients (92.9%) underwent surgical incision. Around half of the patients (45.9%) were treated under local anesthesia. No facial nerve palsy was observed. The most frequently detected pathogens were Streptococci (n = 23), followed by Staphylococcus aureus (n = 6) including one case of methicillin-resistant Staphylococcus aureus. Most patients (68.2%) received an aminopenicillin ± beta-lactamase inhibitor as empiric antibiotic therapy. In 6 cases the antibiotic therapy was modified after receiving the antibiogram. Four patients (5.2%) presented with recurrent PA. Etiology was idiopathic (42.4%), followed by tumorous (12.9%), obstructive, and immunosuppressive (each 11.8%). Patients with a dental focus (p = 0.007) had a longer duration of hospitalization.

CONCLUSION

The results show that the surgical therapy of PA under local anesthesia is safe. A dental examination should routinely be performed to rule out a dental focus. Obtaining a microbiological specimen in order to modify antibiotic therapy if necessary and a histopathological specimen to rule out a tumorous etiology is obligate.

The extracellular matrix landscape in salivary gland carcinomas is defined by cellular differentiation via expression of three distinct protein modules

The extracellular matrix (ECM) is an integral part of the tumor microenvironment of carcinomas. Even though salivary gland carcinomas (SGC) display a range of tumor cell differentiation and distinct extracellular matrices, their ECM landscape has not been characterized in depth. The ECM composition of 89 SGC primaries, 14 metastases and normal salivary gland tissues was assessed using deep proteomic profiling. Machine learning algorithms and network analysis were used to detect tumor groups and protein modules that explain specific ECM landscapes. Multimodal in situ studies to validate exploratory findings and to infer a putative cellular origin of ECM components were applied. We revealed two fundamental SGC ECM classes which align with the presence or absence of myoepithelial tumor differentiation. We describe the SGC ECM through three biologically distinct protein modules that are differentially expressed across ECM classes and cell types. The modules have a distinct prognostic impact on different SGC types. Since targeted therapy is rarely available for SGC, we used the proteomic expression profile to identify putative therapeutic targets. In summary, we provide the first extensive inventory of ECM components in SGC, a difficult-to-treat disease that encompasses tumors with distinct cellular differentiation. This article is protected by copyright. All rights reserved.

[Clinical and molecular epidemiology of malignant salivary gland tumors]

Salivary gland carcinomas are a rare and heterogeneous group of malignant tumors, accounting for 3-6% of all malignant tumors in the head and neck region. The 1-, 3- and 5-year survival rates are 83%, 69% and 63% respectively. Due to new molecular pathological and genetic findings, new entities are constantly being defined as part of the recurring WHO classification of salivary gland carcinomas, so that the incidence rates of the entities are subject to constant change. The only certain risk factor for the development of salivary gland carcinomas is ionizing radiation. In addition, large tumors, cervical lymph node involvement and perineural sheath involvement significantly worsen the prognosis. Today, molecular pathology is coming to the fore, with which potential targets have been identified that can offer prognosis-improving treatment options, particularly in recurrent or distant metastatic stages. Entity-specific tyrosine kinase inhibitors such as axitinib in adenoid cystic carcinoma or larotrectinib in secretory carcinoma and cross-entity therapies such as HER2 inhibition and androgen deprivation can prolong median and progression-free survival with a favorable side effect profile.

Low blood levels of the lncRNA MRPL20-AS1 are associated with severe obstructive sleep apnea

Introduction

Obstructive sleep apnea syndrome (OSAS) is the most common sleep disorder and it is associated with arterial hypertension, heart failure, coronary artery disease as well as atrial fibrillation. The underlying pathomechanisms for this association are only incompletely understood. In recent years long non-coding RNAs (lncRNA) have been shown to be involved in various cardiovascular pathologies. The aim of this study is to identify lncRNAs which are associated with OSAS in order to provide potential therapeutic targets.

Methods and results

In order to tackle this issue, we included 23 Patients with a suspected OSAS in a pilot study and sampled blood on the evening before and on the morning after polysomnographic analysis. Citrate was used to inhibit clotting of the blood and cellular components were removed by centrifugation, before the plasma was stored at −80°C. One patient had no sign of OSAS as indicated by an Apnea/Hypopnea-Index (AHI) &lt;5 per hour and was therefore excluded. The remaining 22 patients had a mean age of 44.45 years and a mean AHI of 28.38 per hour. Three of the patients were female and nineteen were male. In four of those patients with high AHI levels, we performed a RNA sequencing analysis from the citrate plasma and found MRPL20-AS1 to be the most significantly regulated lncRNA after the night of polysomnographic analysis (A). Low coding potential of MRPL20-AS1 was confirmed in silico via the Coding-Potential Assessment Tool (http://lilab.research.bcm.edu/) resulting in a coding probability of 0.06148. Then MRPL20-AS1 levels were measured via qPCR in the remaining patients. From 19 patients, we obtained evaluable results. We found that MRPL20-AS1 blood levels had the tendency to be lower after the night of polysomnographic assessment (B). Interestingly MRPL20-AS1 levels were inversely correlated with the AHI of the OSAS patients (C). This indicates that severe OSAS was associated with low levels of MRPL20-AS1 in our cohort (D). In order to further investigate these results in vitro, we subjected human coronary artery endothelial cells (HCAECs) to hypoxia (1% and 5% O2) for 24 h. We found that hypoxia leads to a significant downregulation of MRPL20-AS1 in HCAECs (E).

Conclusion

MRPL20-AS1 blood levels are lower in patients with severe OSAS after nocturnal hypoxia. In endothelial cells MRPL20-AS1 is downregulated after hypoxia. MRPL20-AS1 can therefore be useful to identify patients suffering from severe OSAS. Further investigations are needed to elucidate the biological function of MRPL20-AS1 in the context of OSAS and to investigate MRPL20-AS1 as a potential therapeutic target to counteract cardiovascular effects of OSAS

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Unviversity of BonnUniversity of Cologne

Analyse und Management von postoperativen Schmerzen nach Sialendoskopie

OBJECTIVE

Sialendocopy is a minimal-invasive technique used for the diagnosis and treatment of salivary gland diseases. The minimal-invasive character of sialendoscopy can be modified by using different surgical techniques. This is why both general and local anaesthesia are applied to perform this procedure and can be of great influence regarding the postoperative pain of those patients. The following study was performed to investigate the level of postoperative pain after sialendoscopy and its pain management.

MATERIAL AND METHODS

103 patients who were treated with a sialendoscopy of the parotid gland or submandibular gland in local anaesthesia between 2013-2015 were included in the study. The postoperative pain level was evaluated at rest and during periods of stress on the day of surgery and the first and second day after surgery. The pain level was analysed according to the numeric rating scale (NRS 0-10), which is used in the QUIPS project (Quality improvement of postoperative pain).

RESULTS

The pain level on the day of surgery was 0,9 ± 1,9 at rest and 0,7 ± 1,4 during periods of stress. On the first postoperative day, pain levels of 1,2 ± 1,8 at rest and 0,9 ± 1,9 during stress were evaluated. On the second day after surgery there was a decrease of pain with a level of 0,75 ± 1,6 at rest and 0,73 ± 1,5 during stress. The analgesic therapy that was mostly used was Metamizol and Ibuprofen. 37,9 % of all patients received analgesic therapy on the day of surgery whereas on the first day after surgery only 26,2 % of all patients and on the second day after surgery only 12,6 % received pain medication.

CONCLUSION

Sialendoscopy of the parotid gland and the submandibular gland is associated with moderate postoperative pain, which can be managed by using non-opioid analgesic therapy.

The Impact of Lesion-Specific and Sampling-Related Factors on Success of Salivary Gland Fine-Needle Aspiration Cytology

PURPOSE

Ultrasound-guided fine-needle aspiration cytology (FNAC) is a widely used diagnostic procedure which facilitates the differentiation of salivary gland lesions. Although the performance of salivary gland FNAC (SG-FNAC) has improved since the introduction of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC), the range of the reported performance is still wide. Therefore, the aim of this study was to determine lesion- and sampling-related factors that influence the success of SG-FNAC.

METHODS

All SG-FNAC cases performed in a tertiary referral hospital between September 1st, 2011, and August 31st, 2022, were retrospectively identified. Demographic, histopathological, lesion-specific, and sampling-related data were retrieved from the clinical charts. Cytopathological reports were categorized according to the MSRSGC. The risk of malignancy (ROM), the performance measures, and factors influencing the success of SG-FNAC were calculated.

RESULTS

Overall, 1289 cases with histopathological follow-up diagnosis (out of 1952 SG-FNACs) were included. The ROM was: non-diagnostic = 23.9%, non-neoplastic = 4.4%, atypia of undetermined significance (AUS) = 34.5%, neoplasm-benign = 1.0%, neoplasm-salivary gland neoplasm of uncertain malignant potential (SUMP) = 15.3%, suspicious for malignancy = 74.1%, malignant = 96.2%. The sensitivity, specificity, accuracy, positive, and negative predictive value for differentiating benign from malignant lesions (excluding lesions categorized as AUS and SUMP) were 87.5%, 97.7%, 96.3%, 85.0%, and 98.1%, respectively. A larger lesion size (OR (95% CI) = 1.21 (1.06-1.39), p = 0.004), a higher number of obtained slides (OR (95% CI) = 1.31 (1.17-1.46), p < 0.001), and the physician performing the FNAC (p = 0.047) were independent predictors for a higher success, while localization of the lesion within the submandibular compared to the parotid gland (OR (95% CI) = 0.38 (0.19-0.77), p = 0.008) was an independent predictor for lower success of SG-FNAC.

CONCLUSION

This is the largest single-center study evaluating SG-FNAC performance to date. It identified independent lesion-and sampling-related factors influencing the success of SG-FNAC. Knowledge of those can improve performance of the procedure.

Expression of Mucins in Different Entities of Salivary Gland Cancer: Highest Expression of Mucin-1 in Salivary Duct Carcinoma : Mucin-1 - highest expression in Salivary Duct Carcinoma

Therapeutic options for advanced salivary gland cancer (SGC) are rare. Therefore, it was the aim of this study to investigate the extent and intensity of Mucin-1 (MUC1), Mucin-16 (MUC16), and Mucin-5AC (MUC5AC) as potential molecular targets using immunohistochemistry. The medical records of all patients who underwent primary surgery for salivary gland cancer with curative intent in a tertiary referral center between 1990 and 2018 were reviewed. Immunohistochemical staining for MUC1, MUC16, and MUC5AC was performed for all patients with sufficient formalin-fixed paraffin-embedded material, and a semi-quantitative combined score derived from the H-score for the cytoplasmatic, the membranous and the apical membrane was built for the most common entities of SGC. 107 patients with malignancies of the parotid (89.7%) and the submandibular gland (10.3%) were included. The most common entities were mucoepidermoid carcinoma (MuEp; n = 23), adenoid cystic carcinoma (AdCy; n = 22), and salivary duct carcinoma (SaDu; n = 21). The highest mean MUC1 combined score was found in SaDu with 223.6 (±91.7). The highest mean MUC16 combined score was found in MuEp with 177.0 (±110.0). The mean MUC5AC score was low across all entities. A higher MUC1 combined score was significantly associated with male gender (p = 0.03), lymph node metastasis (p < 0.01), lymphovascular invasion (p = 0.045), and extracapsular extension (p = 0.03). SaDu patients with MUC16 expression showed a significantly worse 5-year progression-free survival than those without MUC16 expression (p = 0.02). This is the first study to give a comprehensive overview of the expression of MUC1, MUC16, and MUC5AC in SGC. Since advanced SGCs lack therapeutic options in many cases, these results warrant in vitro research on therapeutic targets against MUC1 in SaDu cell lines and xenograft models.

Cancer of the paranasal sinuses in Germany: Data on incidence and survival from a population-based cancer registry

PURPOSE

This study aims to provide a broad overview of the epidemiology of cancer of the paranasal sinuses (PSC) in Germany. The data include information on incidence, staging, clinicopathological features and survival from one of the largest cancer registries in Europe.

METHODS

Population-based data on PSC diagnosed from January 1st, 2009 until December 31st, 2019 were retrieved from the German Centre for Cancer Registry Data (ZfKD). Age standardized incidence was calculated and relative survival estimates were computed by sex, histological subtype, age group and T-, N-, and M-Stage.

RESULTS

In total, 3975 cases were included in this study. The age-adjusted incidence rate (ASR) for PSC was 0.3/100,000 which remained stable during the observation period. The most frequent tumor localization was the maxillary sinus (41.9 %) and the most common histological subtype was keratinizing squamous cell carcinoma (kSCC) (44.3 %). All subtypes were predominantly found in the maxillary sinus except for adenocarcinoma and neuroendocrine carcinomas (SNEC), which were most frequently located in the ethmoidal sinus. The majority of the patients with a known T stage was diagnosed in tumor stage T4 (60.8 %). The overall 5-year relative survival (RS) for all patients with PSC was 52 %. RS dropped from 93 % for T1 stage tumors to 39 % for T4 tumors. RS was 58 % for N0 and 31 % for N+ cases, 54 % for M0 and 27 % for M1 cases.

CONCLUSION

Age-adjusted incidence for PSC is low and has been stable for the observed 11-year period. RS decreases continuously with increasing T-, N- and M-stage.

The extent of androgen receptor and HER2 expression allows for targeted therapy in most cases of salivary duct carcinoma: analysis of clinical and histopathological data in a tertiary care center

PURPOSE

The incidence of salivary duct carcinoma (SDC) seems to be underestimated due to inaccurate classification. Further, the frequency of SDC patients with targeted therapy options according to current guidelines is unclear. Therefore, this study aimed at (a) describing the proportion of SDC among salivary gland carcinoma (SGC) before and after reclassification of cases initially classified as adenocarcinoma, not otherwise specified (ANOS); and (b) quantifying the frequency of SDC patients with targeted therapy options.

METHODS

All patients with SDC or ANOS treated in a tertiary care center between 1996 and 2023 were identified. Histopathological diagnosis was verified for patients primarily diagnosed with SDC and reviewed for patients initially diagnosed with ANOS. Clinical data for SDC patients were retrieved from clinical charts. Immunohistochemical (IHC) androgen receptor (AR) and HER2 staining was performed.

RESULTS

Among 46 SDC, 34 were primarily diagnosed as SDC and 12 had initially been classified as ANOS. The proportion of SDC among SGC was 12.1% and was rising when comparing the time periods 2000-2015 (7.1-11.5%) versus 2016-2023 (15.4-18.1%). Nuclear AR staining in > 70% of tumor cells was found in 56.8% and HER2 positivity (IHC 3 +) in 36.4% of cases. 70.5% of patients showed AR staining in > 70% of tumor cells and/or HER2 positivity and therefore at least one molecular target. 5-year overall and disease-free survival (DFS) were 62.8% and 41.0%. Multivariate Cox regression revealed positive resection margins (HR = 4.0, p = 0.03) as independent negative predictor for DFS.

CONCLUSIONS

The results suggest a rising SDC incidence and show that the extent of the AR and HER2 expression allows for targeted therapy in most SDC cases.