TY - JOUR A1 - Fuchs, Andreas A1 - Hartmann, Stefan A1 - Ernestus, Karen A1 - Mutzbauer, Grit A1 - Linz, Christian A1 - Brands, Roman C. A1 - Kübler, Alexander C. A1 - Müller-Richter, Urs D. A. T1 - Mandibular intraosseous pseudocarcinomatous hyperplasia: a case report JF - Journal of Medical Case Reports N2 - Background Mandibular pseudocarcinomatous hyperplasia is a rare and generally benign pathology. We report on one of these rare cases. Case presentation The case history of a 73-year-old white man stated that he had a carcinoma of the oropharynx, which was primarily treated with radiotherapy and chemotherapy 4 years prior. As a result of radiotherapy he developed an osteoradionecrosis of his mandible and a consecutive pathological fracture of his left mandibular angle. Subsequent osteosynthesis was performed with a reconstruction plate. When we first saw him, his reconstruction plate was partially exposed with intraoral and extraoral fistulation. The resected bone of his defect-bordering jaw showed the typical pathohistological findings of an intraosseous mandibular pseudocarcinomatous hyperplasia. After a first reconstruction attempt with an iliac crest graft failed, definitive reconstruction of his mandible with a microvascular anastomosed fibula graft was achieved. Conclusions Intraosseous pseudocarcinomatous hyperplasia of the mandible is a rare differential diagnosis in maxillofacial surgery. Besides other benign epithelial neoplasms, such as calcifying epithelial odontogenic tumor, squamous odontogenic tumor, or different forms of ameloblastoma, the far more frequent invasive squamous cell carcinoma needs to be excluded. A misinterpretation of pseudocarcinomatous hyperplasia as squamous cell carcinoma must be avoided because it can lead to a massive overtreatment. KW - intraosseous KW - case report KW - pseudocarcinomatous hyperplasia KW - mandible Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146873 VL - 16 IS - 268 ER - TY - THES A1 - Hartmann, Stefan T1 - Vergleichende Analysen zwischen dreidimensionaler und konventioneller Kephalometrie bei Dysgnathiepatienten – Digitale Volumentomographie versus laterales Fernröntgenseitenbild T1 - Comparative analysis between three-dimensional and conventional cephalometry dysgnathic patients – Cone-beam computed tomography vs. lateral radiographs N2 - In der vorliegenden retrospektiven Querschnittstudie wurde untersucht, ob sich zwei- und dreidimensionale Kephalometrie bei Dysgnathiepatienten unterscheidet. Zur Auswertung herangezogen wurden standardisiert aufgenommene Fernröntgenseitenbilder (FRS) und Cone-beam computed tomography (CB-CT)-Scans von 36 Patienten. Alle Patienten wurden in der Universitätsklinik und Poliklink für Mund-, Kiefer- und Plastische Gesichtschirurgie aufgrund ihrer Dysgnathie operativ versorgt. Vor dem Vergleich der konventionellen Schichtaufnahmen und der korrespondierenden Volumina des gleichen Patienten miteinander, wurde zunächst eine Prüfung der Methode für beide Verfahren vorgenommen. Die Ergebnisse wurden statistisch deskriptiv und mithilfe eines Einstichproben-T-Test sowie eines F-Tests ausgewertet und interpretiert. Als Signifikanzniveau wurde p ≤ 0,05 gewählt. In der Studie konnte gezeigt werden, dass sich Untersucher bei der Auswertung eines dreidimensionalen Bildes häufiger und deutlicher unterscheiden als bei einer vergleichbaren Analyse auf Grundlage eines zweidimensionalen Bildes. Die Standardabweichungen waren für die Auswertungen der Volumina kleiner. Insbesondere die Messung der Unterkieferlänge zeigte bei dreidimensionalen Bildern deutliche Unterschiede zwischen beiden Untersuchern. Die große Mehrzahl der anderen Messwerte zeigten hingegen keine relevanten Unterschiede zwischen den Untersuchern. Die Varianzen der Messungen waren für die 3-D-Kephalometrie in 71% bzw. 79% der Fälle kleiner als in einer vergleichbaren zweidimensionalen FRS-Messung. Es zeigte sich kein Anhalt für Zusammenhänge zwischen der Anzahl der Referenzpunkte, die einer Messung zugrunde liegen und der entsprechenden Varianz des untersuchten Parameters. Beim direkten Vergleich zwischen zwei- und dreidimensionalem Bild wurden bei 66% der paramedianen Parameter, aber nur bei 25% der medianen Variablen gemittelte Differenzen von mehr als einem Millimeter bzw. Grad festgestellt. Es kommt also bei Parametern, die außerhalb der Schädelmedian-Ebene liegen, häufiger zu klinisch relevanten Differenzen zwischen lateralem FRS und CB-CT. Die CB-CT kann zusammen mit der 3D-Kephalometrie bei Patienten mit fazialen Asymmetrien einen Zugewinn an Information gegenüber der konventionellen Schichtaufnahme bedeuten. Hier zeigen sich die Vorteile einer überlagerungsfreien und präzisen Darstellung des Gesichtsschädels klar. N2 - The purpose of the present retrospective cross-sectional study was to review if the method of a two-dimensional cephalometric measurement distinguishes significantly from a three-dimensional measurement. For its interpretation standardized cone-beam computed tomographs (CBCT) and lateral radiographs (Ceph) of 36 dysgnatic patients have been used. All tested subjects underwent orthognathic surgeries at the Department of Cranio-Maxillo-Facial Surgery at the University of Würzburg (Bavaria/Germany). Before comparing the test results of the same test subject (derived by conventional radiographs and CBCT scans) different test methods have been reviewed. The results of the tests have been statistically evaluated and analyzed by an F test together with an T test for unpaired and indepented samples with a significance level of p ≤ 0.05. The study shows that observers disagree significantly more often, obvious and distinct when it comes to three-dimensional measurement of dysgnathic patients compared to a two-dimensional examination (standard deviation for CBCT measurements was significantly smaller). In particular measurement of the length of the mandible shows clearly distinctions between the two tested methods. Whereas the majority of the other measured data does not show notable relevant differences. The variances of the three-dimensional measurements have been in 71% (respectively 79% of the cases) smaller than the two-dimensional cephalometric measurement method. There was no sign for coherence between the number of reference points and the corresponding variances of the examined parameters. In a straight comparison between two-dimensional and three-dimensional images was in 66% of the cases (paramedian parameter) and 25% of the cases (median parameter) an averaged difference of one millimeter or degree. It is safe to say that in terms of parameter outside the skull median there are more often clinical relevant differences between lateral radiograph and the CB-CT method to observe. CB-CT method combined with three-dimensional measurement of dysgnathic patients can gain an information plus towards a conventional lateral method and shows clearly the benefits of an accurate and non-overlapping image of the viscerocranium. KW - Kraniometrie KW - Volumentomographie KW - Fernröntgenseitenbild KW - Dysgnathie KW - Kraniometrie KW - Volumentomographie KW - Fernröntgenseitenbild KW - Dysgnathie KW - Kephalometrie KW - Cephalometry KW - CBCT KW - lateral radiograph KW - malocclusion Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-51407 ER - TY - JOUR A1 - Hartmann, Stefan A1 - Lessner, Grit A1 - Mentzel, Thomas A1 - Kübler, Alexander C. A1 - Müller-Richter, Urs T1 - An adult spindle cell rhabdomyosarcoma in the head and neck region with long-term survival: a case report N2 - Introduction Spindle cell rhabdomyosarcoma of the head and neck is a very rare tumor in adults. We report on one case with long-term survival. Case presentation A 41-year-old nonsmoking Caucasian man presented in June 2007 with a painless swelling under his tongue. A diagnosis of a soft tissue sarcoma, and a myofibrosarcoma in particular, was made via biopsy. After multimodal treatment, including local and systemic therapy, our patient remained disease-free until September 2010. The local recurrence was treated unsuccessfully with various chemotherapy regimens. In September 2011, our patient underwent surgical resection again, and a spindle cell rhabdomyosarcoma was diagnosed. To analyze the mismatch between the original diagnosis of a myofibrosarcoma and the second diagnosis, the two specimens were reassessed, and a final diagnosis of a spindle cell rhabdomyosarcoma was made. In 2012 and 2013, our patient suffered further recurrences that were surgically treated, and he is still alive with disease six years and 10 months after the initial diagnosis in June 2007. Conclusions In adults, the spindle cell rhabdomyosarcoma tumor is very rare in the head and neck region. In contrast to childhood tumors, spindle cell rhabdomyosarcoma in adulthood is often associated with a poor prognosis. In the present case, the radical surgical treatment might have helped to prolong the patient’s overall survival, which has lasted more than six years. To our knowledge, this is the longest overall survival reported so far for this tumor entity in the head and neck region. KW - Rhabdomyosarcoma KW - Spindle cell KW - Adult KW - Surgery KW - Head Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110362 ER - TY - JOUR A1 - Boschert, Verena A1 - Klenk, Nicola A1 - Abt, Alexander A1 - Raman, Sudha Janaki A1 - Fischer, Markus A1 - Brands, Roman C. A1 - Seher, Axel A1 - Linz, Christian A1 - Müller-Richter, Urs D. A. A1 - Bischler, Thorsten A1 - Hartmann, Stefan T1 - The influence of Met receptor level on HGF-induced glycolytic reprogramming in head and neck squamous cell carcinoma JF - International Journal of Molecular Sciences N2 - Head and neck squamous cell carcinoma (HNSCC) is known to overexpress a variety of receptor tyrosine kinases, such as the HGF receptor Met. Like other malignancies, HNSCC involves a mutual interaction between the tumor cells and surrounding tissues and cells. We hypothesized that activation of HGF/Met signaling in HNSCC influences glucose metabolism and therefore substantially changes the tumor microenvironment. To determine the effect of HGF, we submitted three established HNSCC cell lines to mRNA sequencing. Dynamic changes in glucose metabolism were measured in real time by an extracellular flux analyzer. As expected, the cell lines exhibited different levels of Met and responded differently to HGF stimulation. As confirmed by mRNA sequencing, the level of Met expression was associated with the number of upregulated HGF-dependent genes. Overall, Met stimulation by HGF leads to increased glycolysis, presumably mediated by higher expression of three key enzymes of glycolysis. These effects appear to be stronger in Met\(^{high}\)-expressing HNSCC cells. Collectively, our data support the hypothesized role of HGF/Met signaling in metabolic reprogramming of HNSCC. KW - HNSCC KW - head and neck cancer KW - HGF KW - Met KW - cancer metabolism Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235995 SN - 1422-0067 VL - 21 IS - 2 ER - TY - JOUR A1 - Linz, Christian A1 - Faber, Julian A1 - Schmid, Reiner A1 - Kunz, Felix A1 - Böhm, Hartmut A1 - Hartmann, Stefan A1 - Schweitzer, Tilmann T1 - Using a 3D asymmetry index as a novel form for capturing complex three-dimensionality in positional plagiocephaly JF - Scientific Reports N2 - Positional plagiocephaly (PP) is the most common skull deformity in infants. Different classification systems exist for graduating the degree of PP, but all of these systems are based on two-dimensional (2D) parameters. This limitation leads to several problems stemming from the fact that 2D parameters are used to classify the three-dimensional (3D) shape of the head. We therefore evaluate existing measurement parameters and validate a newly developed 3D parameter for quantifying PP. Additionally, we present a new classification of PP based on a 3D parameter. 210 patients with PP and 50 patients without PP were included in this study. Existing parameters (2D and 3D) and newly developed volume parameters based on a 3D stereophotogrammetry scan were validated using ROC curves. Additionally, thresholds for the new 3D parameter of a 3D asymmetry index were assessed. The volume parameter 3D asymmetry index quantifies PP equally as well as the gold standard of 30° diagonal difference. Moreover, a 3D asymmetry index allows for a 3D-based classification of PP. The 3D asymmetry index can be used to define the degree of PP. It is easily applicable in stereophotogrammetric datasets and allows for comparability both intra- and inter-individually as well as for scientific analysis. KW - craniofacial orthodontics KW - physical examination KW - three-dimensional imaging Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300427 VL - 12 ER - TY - JOUR A1 - Straub, Anton A1 - Brands, Roman A1 - Borgmann, Anna A1 - Vollmer, Andreas A1 - Hohm, Julian A1 - Linz, Christian A1 - Müller-Richter, Urs A1 - Kübler, Alexander C. A1 - Hartmann, Stefan T1 - Free skin grafting to reconstruct donor sites after radial forearm flap harvesting: a prospective study with platelet-rich fibrin (PRF) JF - Journal of Clinical Medicine N2 - Reconstruction of the donor site after radial forearm flap harvesting is a common procedure in maxillofacial plastic surgery. It is normally carried out with split-thickness or full-thickness free skin grafts. Unfortunately, free skin graft transplantation faces wound healing impairments such as necrosis, (partial) graft loss, or tendon exposure. Several studies have investigated methods to reduce these impairments and demonstrated improvements if the wound bed is optimised, for example, through negative-pressure wound therapy or vacuum-assisted closure. However, these methods are device-dependent, expansive, and time-consuming. Therefore, the application of platelet-rich fibrin (PRF) to the wound bed could be a simple, cost-effective, and device-independent method to optimise wound-bed conditions instead. In this study, PRF membranes were applied between the wound bed and skin graft. Results of this study indicate improvements in the PRF versus non-PRF group (93.44% versus 86.96% graft survival, p = 0.0292). PRF applied to the wound bed increases graft survival and reduces impairments. A possible explanation for this is the release of growth factors, which stimulate angiogenesis and fibroblast migration. Furthermore, the solid PRF membranes act as a mechanical barrier (“lubrication” layer) to protect the skin graft from tendon motion. The results of this study support the application of PRF in donor-site reconstruction with free skin grafts. KW - platelet-rich fibrin KW - free skin grafts KW - radial forearm flap KW - donor-site morbidity Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-278854 SN - 2077-0383 VL - 11 IS - 12 ER - TY - JOUR A1 - Koderer, Corinna A1 - Schmitz, Werner A1 - Wünsch, Anna Chiara A1 - Balint, Julia A1 - El-Mesery, Mohamed A1 - Volland, Julian Manuel A1 - Hartmann, Stefan A1 - Linz, Christian A1 - Kübler, Alexander Christian A1 - Seher, Axel T1 - Low energy status under methionine restriction is essentially independent of proliferation or cell contact inhibition JF - Cells N2 - Nonlimited proliferation is one of the most striking features of neoplastic cells. The basis of cell division is the sufficient presence of mass (amino acids) and energy (ATP and NADH). A sophisticated intracellular network permanently measures the mass and energy levels. Thus, in vivo restrictions in the form of amino acid, protein, or caloric restrictions strongly affect absolute lifespan and age-associated diseases such as cancer. The induction of permanent low energy metabolism (LEM) is essential in this process. The murine cell line L929 responds to methionine restriction (MetR) for a short time period with LEM at the metabolic level defined by a characteristic fingerprint consisting of the molecules acetoacetate, creatine, spermidine, GSSG, UDP-glucose, pantothenate, and ATP. Here, we used mass spectrometry (LC/MS) to investigate the influence of proliferation and contact inhibition on the energy status of cells. Interestingly, the energy status was essentially independent of proliferation or contact inhibition. LC/MS analyses showed that in full medium, the cells maintain active and energetic metabolism for optional proliferation. In contrast, MetR induced LEM independently of proliferation or contact inhibition. These results are important for cell behaviour under MetR and for the optional application of restrictions in cancer therapy. KW - methionine restriction KW - caloric restriction KW - mass spectrometry KW - LC/MS KW - liquid chromatography/mass spectrometry KW - metabolomics KW - L929 KW - amino acid KW - proliferation KW - contact inhibition Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262329 SN - 2073-4409 VL - 11 IS - 3 ER - TY - JOUR A1 - Vollmer, Andreas A1 - Vollmer, Michael A1 - Lang, Gernot A1 - Straub, Anton A1 - Kübler, Alexander A1 - Gubik, Sebastian A1 - Brands, Roman C. A1 - Hartmann, Stefan A1 - Saravi, Babak T1 - Performance analysis of supervised machine learning algorithms for automatized radiographical classification of maxillary third molar impaction JF - Applied Sciences N2 - Background: Oro-antral communication (OAC) is a common complication following the extraction of upper molar teeth. The Archer and the Root Sinus (RS) systems can be used to classify impacted teeth in panoramic radiographs. The Archer classes B-D and the Root Sinus classes III, IV have been associated with an increased risk of OAC following tooth extraction in the upper molar region. In our previous study, we found that panoramic radiographs are not reliable for predicting OAC. This study aimed to (1) determine the feasibility of automating the classification (Archer/RS classes) of impacted teeth from panoramic radiographs, (2) determine the distribution of OAC stratified by classification system classes for the purposes of decision tree construction, and (3) determine the feasibility of automating the prediction of OAC utilizing the mentioned classification systems. Methods: We utilized multiple supervised pre-trained machine learning models (VGG16, ResNet50, Inceptionv3, EfficientNet, MobileNetV2), one custom-made convolutional neural network (CNN) model, and a Bag of Visual Words (BoVW) technique to evaluate the performance to predict the clinical classification systems RS and Archer from panoramic radiographs (Aim 1). We then used Chi-square Automatic Interaction Detectors (CHAID) to determine the distribution of OAC stratified by the Archer/RS classes to introduce a decision tree for simple use in clinics (Aim 2). Lastly, we tested the ability of a multilayer perceptron artificial neural network (MLP) and a radial basis function neural network (RBNN) to predict OAC based on the high-risk classes RS III, IV, and Archer B-D (Aim 3). Results: We achieved accuracies of up to 0.771 for EfficientNet and MobileNetV2 when examining the Archer classification. For the AUC, we obtained values of up to 0.902 for our custom-made CNN. In comparison, the detection of the RS classification achieved accuracies of up to 0.792 for the BoVW and an AUC of up to 0.716 for our custom-made CNN. Overall, the Archer classification was detected more reliably than the RS classification when considering all algorithms. CHAID predicted 77.4% correctness for the Archer classification and 81.4% for the RS classification. MLP (AUC: 0.590) and RBNN (AUC: 0.590) for the Archer classification as well as MLP 0.638) and RBNN (0.630) for the RS classification did not show sufficient predictive capability for OAC. Conclusions: The results reveal that impacted teeth can be classified using panoramic radiographs (best AUC: 0.902), and the classification systems can be stratified according to their relationship to OAC (81.4% correct for RS classification). However, the Archer and RS classes did not achieve satisfactory AUCs for predicting OAC (best AUC: 0.638). Additional research is needed to validate the results externally and to develop a reliable risk stratification tool based on the present findings. KW - oro-antral communication KW - oro-antral fistula KW - prediction KW - machine learning KW - teeth extraction KW - complications KW - classification KW - artificial intelligence Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281662 SN - 2076-3417 VL - 12 IS - 13 ER - TY - JOUR A1 - Scheurer, Mario Joachim Johannes A1 - Brands, Roman Camillus A1 - El-Mesery, Mohamed A1 - Hartmann, Stefan A1 - Müller-Richter, Urs Dietmar Achim A1 - Kübler, Alexander Christian A1 - Seher, Axel T1 - The selection of NFκB inhibitors to block inflammation and induce sensitisation to FasL-induced apoptosis in HNSCC cell lines is critical for their use as a prospective cancer therapy JF - International Journal of Molecular Science N2 - Inflammation is a central aspect of tumour biology and can contribute significantly to both the origination and progression of tumours. The NFκB pathway is one of the most important signal transduction pathways in inflammation and is, therefore, an excellent target for cancer therapy. In this work, we examined the influence of four NFκB inhibitors — Cortisol, MLN4924, QNZ and TPCA1 — on proliferation, inflammation and sensitisation to apoptosis mediated by the death ligand FasL in the HNSCC cell lines PCI1, PCI9, PCI13, PCI52 and SCC25 and in the human dermal keratinocyte cell line HaCaT. We found that the selection of the inhibitor is critical to ensure that cells do not respond by inducing counteracting activities in the context of cancer therapy, e.g., the extreme IL-8 induction mediated by MLN4924 or FasL resistance mediated by Cortisol. However, TPCA1 was qualified by this in vitro study as an excellent therapeutic mediator in HNSCC by four positive qualities: (1) proliferation was inhibited at low μM-range concentrations; (2) TNFα-induced IL-8 secretion was blocked; (3) HNSCC cells were sensitized to TNFα-induced cell death; and (4) FasL-mediated apoptosis was not disrupted. KW - HNSCC KW - NFκB KW - inhibitor KW - TPCA1 KW - apoptosis KW - inflammation KW - TNFα KW - FasL Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201524 SN - 1422-0067 VL - 20 IS - 6 ER - TY - JOUR A1 - Boschert, Verena A1 - Teusch, Jonas A1 - Aljasem, Anwar A1 - Schmucker, Philipp A1 - Klenk, Nicola A1 - Straub, Anton A1 - Bittrich, Max A1 - Seher, Axel A1 - Linz, Christian A1 - Müller-Richter, Urs D. A. A1 - Hartmann, Stefan T1 - HGF-induced PD-L1 expression in head and neck cancer: preclinical and clinical findings JF - International Journal of Molecular Sciences N2 - Head and neck squamous cell carcinoma (HNSCC) is a widespread disease with a low survival rate and a high risk of recurrence. Nowadays, immune checkpoint inhibitor (ICI) treatment is approved for HNSCC as a first-line treatment in recurrent and metastatic disease. ICI treatment yields a clear survival benefit, but overall response rates are still unsatisfactory. As shown in different cancer models, hepatocyte growth factor/mesenchymal–epithelial transition (HGF/Met) signaling contributes to an immunosuppressive microenvironment. Therefore, we investigated the relationship between HGF and programmed cell death protein 1 (PD-L1) expression in HNSCC cell lines. The preclinical data show a robust PD-L1 induction upon HGF stimulation. Further analysis revealed that the HGF-mediated upregulation of PD-L1 is MAP kinase-dependent. We then hypothesized that serum levels of HGF and soluble programmed cell death protein 1 (sPD-L1) could be potential markers of ICI treatment failure. Thus, we determined serum levels of these proteins in 20 HNSCC patients before ICI treatment and correlated them with treatment outcomes. Importantly, the clinical data showed a positive correlation of both serum proteins (HGF and sPD-L1) in HNSCC patient’s sera. Moreover, the serum concentration of sPD-L1 was significantly higher in ICI non-responsive patients. Our findings indicate a potential role for sPD-L1 as a prognostic marker for ICI treatment in HNSCC. KW - HNSCC KW - head and neck cancer KW - HGF KW - Met KW - PD-L1 KW - immune therapy Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236220 SN - 1422-0067 VL - 21 IS - 20 ER -