Routine panendoscopy in oral squamous cell cancer patients: mandatory or facultative?

OBJECTIVES: This study investigated benefits of routine panendoscopy in staging of oral squamous cell cancer patients. MATERIALS AND METHODS: From 2013 to 2017, 194 oral squamous cell cancer patients were staged. Reports of routine flexible panendoscopy including oropharyngolaryngoscopy, bronchoscopy, and esophagogastroduodenoscopy were retrospectively analyzed for diagnoses of inflammation and second primary malignancies (carcinoma in situ or cancer) and compared to results of computed tomography. The effects of alcohol and tobacco history of 142 patients were assessed. RESULTS: Overall, a second primary malignancy was detected in seven patients. In four patients this discovery was only found by panendoscopy. One invasive carcinoma (esophagus) was detected as well as three carcinoma in situ. The second primary malignancies were located in the lung (3), esophagus (3), and stomach (1). In one patient index tumor therapy was modified after panendoscopy. Upper gastrointestinal inflammation was present in 73.2% of patients and 61.9% required treatment. About 91.8% of bronchoscopies and 34.5% of panendoscopies were without therapeutic consequences. Patients with higher risk from smoking were more likely to benefit from panendoscopy and to have a Helicobacter pylori infection. CONCLUSION: We do not recommend routine panendoscopy for all oral squamous cell cancer patients. Esophagogastroduodenoscopy benefitted smoking patients primarily concerning the secondary diagnosis of inflammation of the upper digestive tract. Selective bronchoscopy, esophagogastroduodenoscopy, and oropharyngolaryngoscopy should be performed if clinical examination or medical history indicates risks for additional malignancies of the upper aerodigestive tract. CLINICAL RELEVANCE: Routine panendoscopy is not recommended in all, especially not in low-risk oral cancer patients like non-smokers and non-drinkers.

Change in reimbursement and costs in German oncological head and neck surgery over the last decade: ablative tongue cancer surgery and reconstruction with split-thickness skin graft vs. microvascular radial forearm flap.

OBJECTIVES: Defects after ablative tongue cancer surgery can be reconstructed by split-thickness skin grafts or free microvascular flaps. The different surgical options may influence costs, reimbursement, and therefore possible profits. Our goal was to analyze the development of these parameters for different procedures in head and neck reconstruction in Germany over the last decade. MATERIALS AND METHODS: After tumor resection and neck dissection of tongue cancer, three different scenarios were chosen to calculate costs, reimbursement, length of stay (LoS), and profits. Two options considered were reconstruction by split-thickness skin graft with (option Ia) and without (option Ib) tracheotomy. In addition, we analyzed microvascular reconstruction with radial forearm flap (option II). Furthermore, unsatisfactory results after options Ia and Ib may make secondary tongue plastic with split-thickness skin grafting necessary (option I+). The calculations were performed considering the German Diagnosis Related Group (DRG) system and compared to the specific DRG cost data of 250 German reference hospitals. RESULTS: The overall average length of stay (aLoS) declined from 16.7 to 12.8 days with a reduction in every option. Until 2011, all options showed similar accumulated DRG reimbursement. From 2012 onwards, earnings almost doubled for option II due to changes in the DRG allocation. As was expected, the highest costs were observed in option II. Profits (reimbursement minus costs) were also highest for option II (mean 2052 €, maximum 3630 Euros in 2015) followed by options Ia (765 €) and Ib/I+ (681 €). Average profits over time would be 17 to 19% higher if adjusted for inflation. CONCLUSIONS: We showed the development of the DRG allocation of two commonly used methods of reconstruction after ablative tongue cancer surgery and the associated LoS, reimbursement, costs, and profits. As expected, the highest values were found for microvascular reconstruction. Microvascular reconstruction may also be the primary choice of treatment from a medical point of view. However, prolonged operation times, intensive care, and hospital stay in connection with complex microvascular operations can easily turn profits into losses as opposed to the results of simple, reliable, and fast split-thickness skin grafting. The inflation rate influences profits in reimbursement systems where costs are based on a previous period of time. CLINICAL RELEVANCE: Surgeons find themselves daily in an area of conflict between economic interests and medical decision-making. Due to its multidimensional aspects, the choice of the reconstructive technique should be primarily based on the best medical care for the patient. But there should also be awareness of the economic risk of all three surgical procedures.

Standardized pretreatment inflammatory laboratory markers and calculated ratios in patients with oral squamous cell carcinoma.

Analyzing the inflammatory microenvironment has become an important issue in the management of oral squamous cell carcinoma (OSCC). Pretreatment C-reactive protein (CRP) levels, leucocytes, monocytes, lymphocytes, neutrophils, basophils, eosinophils, platelets, neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) derived from the peripheral blood were analyzed. Receiver operating characteristic (ROC) curves determined a cut-off value for each parameter in 146 patients with OSCC compared with 93 controls and the results were associated with clinicopathological characteristics. CRP expression of tumors was measured by immunohistochemistry. ROC analysis determined cut-off values for CRP levels, leucocytes, monocytes, lymphocytes, neutrophils, NLR, dNLR, LMR, PLR and showed significant differences between the OSCC and control group. Compared with single laboratory tests calculated ratios were superior in measuring sensitivity and specificity of OSCC disease. NLR was significant directly associated and correlated with PLR. LMR was significant inversely associated and correlated with NLR and PLR. Immunohistochemical analysis did not show CRP expression of OSCCs. This study highlights the first analysis for cut-off values of pretreatment single laboratory tests and calculated ratios, which are strongly needed for a follow-up of cancer patients. Additionally, the calculated baselines can be used as a goal for successful immunotherapies in the future. The links between NLR, LMR, and PLR might be helpful for the clinical course (monitoring) of cancer patients and have been first described for OSCC in this study. Taken together, analyzing these data provides an additional practical guideline of further postoperative OSCC management.

Altered macrophagic THP-1 cell phagocytosis and migration in bisphosphonate-related osteonecrosis of the jaw (BRONJ).

OBJECTIVES: Local immune dysfunction via macrophages is a proposed aetiology of bisphosphonate-related osteonecrosis of the jaw (BRONJ). This study aimed to clarify the effects of various bisphosphonates on macrophage function using a THP-1 monocytic model to examine migration, phagocytosis, and fibrin structure. MATERIALS AND METHODS: THP-1 cell migration was measured in the presence and absence of zoledronate, ibandronate, risedronate, alendronate, pamidronate (0.5, 5 and 50 µM) and clodronate (125, 250 and 500 µM) using the real-time xCELLigence system. Phagocytosis and actin fibre assays were performed after 72 h with zoledronate, ibandronate, alendronate and clodronate. RESULTS: Time to maximum migration for THP-1 cells was significantly reduced (p < 0.05) for high dosages of zoledronate, ibandronate and alendronate compared to controls. All dosages of clodronate and a low dose of zoledronate exhibited prolonged migrations. Phagocytic capacity was significantly reduced in high dosages of all bisphosphonates and for 5 µM zoledronate and ibandronate (p < 0.05). Low bisphosphonate exposure was accompanied by overcharged phagosoms. Altered appearance in F-actin fibrin structure was observed in bisphosphonate-exposed cells. CONCLUSIONS: All bisphosphonates altered the migration of THP-1 cells dose-dependently. Low doses also prolonged migration and altered cell morphology. These findings support the idea of a disturbed local immune function of macrophages even in jaw bone exposed to low concentrations of bisphosphonate. CLINICAL RELEVANCE: These are the first real-time results for disrupted migration and function of macrophagic THP-1 cells in high doses. Low dosages also demonstrated altered macrophage phagocytosis and cell morphology, suggesting a disturbed local immune function in BRONJ pathogenesis.

Evaluation of a biomarker based blood test for monitoring surgical resection of oral squamous cell carcinomas.

INTRODUCTION: The potential use of determination of biomarkers in blood for the monitoring of surgical removal of oral squamous cell carcinomas (OSCC) was evaluated using the epitope detection in monocytes (EDIM) technology. MATERIALS AND METHODS: In tumor specimen, elevated Apo10 and transketolase-like 1 (TKTL1) expression was analyzed by immunohistochemistry. Apo10 and TKTL1 biomarkers have been used prospectively for EDIM blood test in patients with primary and/or recurrent OSCC (n = 92) before surgery and after curative tumor resection (n = 45). RESULTS: There were highly significant (p < 0.0001) correlations found between EDIM blood scores and the tissue expression of both biomarkers measured by immunohistochemistry (Apo10: n = 89/92, 97%; TKTL1: n = 90/92, 98%). EDIMApo10 and EDIM-TKTL1 scores were positive in 92% (EDIM-Apo10: n = 85/92) and 93% (EDIM-TKTL1: n = 86/92), respectively, in patients with OSCC before surgery. The combined score EDIM-Apo10/EDIM-TKTL1 increased significantly the detection rate of tumors to 97% (n = 89/92). After surgery, the EDIM-TKTL1 and EDIMApo10 scores significantly decreased in 75.6 and 86.7% of the patients (p < 0.0001), respectively, in the aftercare. CONCLUSIONS: The correlation of TKTL1 and Apo10 immunohistochemistry with the blood test results indicates that the EDIM blood test could serve as a non-invasive diagnostic tool (liquid biopsy) to assess surgical removal of OSCC by determination of two biomarkers. CLINICAL RELEVANCE: This is the first study that has been demonstrated a reliable and successful monitoring of OSCC cancer patients by a blood test. The specific and significant decrease of EDIM-TKTL1 and EDIM-Apo10 scores after surgery could serve as a new tool for monitoring surgical removal of OSCC.

Macrophages and bisphosphonate-related osteonecrosis of the jaw (BRONJ): evidence of local immunosuppression of macrophages in contrast to other infectious jaw diseases.

OBJECTIVES: Bisphosphonates (BIP) are well established in bone diseases. A serious side effect is the bisphosphonate-related osteonecrosis of the jaw (BRONJ). Among different aetiology factors, local suppression of immune functions is gaining interest. The aim of this study was to analyze the function of macrophages in BRONJ in contrast to patients with osteoradionecrosis (ORN) and secondary chronic osteomyelitis (OM) of the jaws. Samples were also taken from patients with bisphosphonate medication (BP) without signs of infection, radiation therapy (RA), and osteoporosis (OP) as controls. MATERIAL AND METHODS: One hundred five patients with surgery to the jaw were included in this study: 33 patients with BRONJ, 17 with ORN, 11 with secondary chronic OM, 8 with RA, 25 with BP medication and 11 with OP. Samples were histologically analysed and monocytes/macrophages stained using CD14 and CD68. The number of positively marked cells was counted per view (pv), and the CD68/CD14 ratio was calculated. Statistically, the Naïve-Bayes and decision-tree classifier were used. RESULTS: The number of CD14 positive cells was 10.3 cells/pv in the BRONJ-group in as compared to 5 in the ORN- and 3.8 in the OM-group respectively. The number of CD68 positive cells was 11.4/pv (BRONJ-group) as compared to 14/pv (ORN-group) and 12.7/pv (OM-group). With 0.89, the BRONJ-group showed a statistically different CD68/CD14 ratio than ORN-group with 3.39 and OM-group with 3.03. CONCLUSIONS: Our results indicate a different expression of CD14 and CD68 markers of monocytes/macrophages in BRONJ as compared to other jaw infections. This could be a sign of macrophage immunosuppression by BPs. In contrast, patients receiving BP medication without BRONJ showed no differences to other controls. CLINICAL RELEVANCE: This is the first study that clinically indicates a compromised macrophage function at BRONJ sites in contrast to ORN or secondary OM sites. The BRONJ itself could be forwarded by this effect.

Zoledronate but not denosumab suppresses macrophagic differentiation of THP-1 cells. An aetiologic model of bisphosphonate-related osteonecrosis of the jaw (BRONJ).

OBJECTIVES: Bisphosphonates and denosumab are antiresorptive drugs used for the treatment of osteoporosis and oncological tumors. A severe side effect is osteonecrosis of the jaw. Monocyte/macrophage dysfunction is considered to play a distinct role in osteonecrosis. THP-1 monocytic cells were used in this study to elucidate the influence of zoledronate and denosumab on phorbol-12-myrisate-13-acetate (PMA)-induced macrophage differentiation and function in real-time. MATERIALS AND METHODS: Macrophagic differentiation of the THP-1 suspension cells was measured by cell adherence in the presence or absence of different concentrations of zoledronate (0.5, 5, 50 µM) and denosumab (1, 10, 20, 40 µg/mL) using the real-time xCELLigence system. Additionally, a live/dead staining was performed by fluorescence microscopy. RESULTS: THP-1 cells demonstrated a regular initial PMA-induced differentiation to macrophages by live measurements of cell adherence and by an increase in CD68 surface expression as detected by flow cytometry. The addition of zoledronate led to cell detachment of the THP-1-derived macrophages in a dose-dependent manner in contrast to denosumab. Cell detachment was based on cell death as confirmed by live/dead staining, revealing elevated numbers of dead cells following addition of high zoledronate concentrations. However, denosumab did not deteriorate THP-1 cell viability. CONCLUSION: Our results demonstrate that zoledronate but not denosumab suppresses monocytic THP-1 cell viability after macrophagic differentiation dose-dependently. CLINICAL RELEVANCE: This is the first real-time study providing evidence for a dose-dependent immunosuppressive effect of zoledronate in contrast to denosumab on local macrophages.

Co-expression of CD44+/RANKL+ tumor cells in the carcinogenesis of oral squamous cell carcinoma.

Receptor activator of nuclear factor-kappa (RANK)/receptor activator of nuclear factor-kappa B ligand (RANKL) signaling helps putative cancer stem cells (CSC) to maintain their stemness. Expression of CD44 and RANKL was analyzed in oral squamous cell carcinoma specimen (n = 191). Moreover, RANKL expression was measured in cancer cell lines (BICR3, BICR56) by immunohistochemistry and western blot analysis. Scanned images were digitally analyzed using ImageJ and the immunomembrane plug-in. CD44 and RANKL expression on protein level was correlated with clinical characteristics and impact on survival. RANKL was co-labeled with CD44 in immunohistochemical and immunofluorescence double labeling experiments. Although high CD44+/RANKL+ co-expression was significantly associated with clinicopathological factors and worse survival, multivariate analysis did not demonstrate high CD44+/RANKL+ co-expression as independent prognostic factor. Immunohistochemical and immunofluorescence double labeling experiments revealed RANKL expression by CD44+ cancer cells. RANKL specificity was confirmed by western blot analysis. For the first time, this study provides evidence that RANKL expression in OSCC might be associated with disease recurrence and a cell compartment measured by CD44+/RANKL+ co-expression within the mucosal epithelial basal layer cells.

Reimbursement for reconstruction by tissue transfer-a European comparison.

BACKGROUND: Case payment mechanisms have become the principal means of remunerating hospitals in most developed countries. Our purpose was to analyse the reimbursement for different types of tissue transfer in five European countries. METHODS: We looked at common surgical options for pedicled and free flaps. The recipient site of a flap and the principal diagnosis were systematically modified and processed with national grouper software in order to identify Diagnosis-Related Groups from which the proceeds were derived. The primary data originated from the database of the German Institute for the Hospital Remuneration System as aggregate information. We conducted eight specialist interviews to transfer the available data into clinical practice. Data of real patients were not available and we rather simulated standard patients to avoid dilution of results. RESULTS: Altogether, payment for pedicled flaps averaged 5933€ and was 8517€ for free flaps. The comparison of both flap types within a country revealed significant differences in Germany, Austria and Sweden only (p < 0.001). Italy has the highest mean proceeds for pedicled flaps, followed by Sweden, Germany, Austria and the UK. This relationship changes for free flaps with Sweden achieving the highest payments. Overall, reimbursement conformity is higher for free flaps. CONCLUSIONS: Most countries have procedure-driven payment systems for flap surgery, which additionally can strongly depend on the diagnosis. Nevertheless the latter does not always justify existing price differences. For the first time, clinical cases in tissue transfer were compared internationally. In today`s dynamic world of health care, we should observe other countries` compensation systems to identify ways of improving our own.

Synthetic, non-person related panoramic radiographs created by generative adversarial networks in research, clinical, and teaching applications.

OBJECTIVES: Generative Adversarial Networks (GANs) can produce synthetic images free from personal data. They hold significant value in medical research, where data protection is increasingly regulated. Panoramic radiographs (PRs) are a well-suited modality due to their significant level of standardization while simultaneously displaying a high degree of personally identifiable data. METHODS: We produced synthetic PRs (syPRs) out of real PRs (rePRs) using StyleGAN2-ADA by NVIDIA©. A survey was performed on 54 medical professionals and 33 dentistry students. They assessed 45 radiological images (20 rePRs, 20 syPRs, and 5 syPRcontrols) as real or synthetic and interpreted a single-image syPR according to the image quality (0-10) and 14 different items (agreement/disagreement). They also rated the importance for the profession (0-10). A follow-up was performed for test-retest reliability with >10 % of all participants. RESULTS: Overall, the sensitivity was 78.2 % and the specificity was 82.5 %. For professionals, the sensitivity was 79.9 % and the specificity was 82.3 %. For students, the sensitivity was 75.5 % and the specificity was 82.7 %. In the single syPR-interpretation image quality was rated at a median of 6 and 11 items were considered as agreement. The importance for the profession was rated at a median score of 7. The Test-retest reliability yielded a value of 0.23 (Cohen's kappa). CONCLUSIONS: The study marks a comprehensive testing to demonstrate that GANs can produce synthetic radiological images that even health professionals can sometimes not differentiate from real radiological images, thereby being genuinely considered authentic. This enables their utilization and/or modification free from personally identifiable information. CLINICAL SIGNIFICANCE: Synthetic images can be used for university teaching and patient education without relying on patient-related data. They can also be utilized to upscale existing training datasets to improve the accuracy of AI-based diagnostic systems. The study thereby supports clinical teaching as well as diagnostic and therapeutic decision-making.

Preoperative Assessment of Medication-Related Osteonecrosis of the Jaw Using [18F]fluoride Positron Emission Tomography (PET)/CT and [18F]fluorodeoxyglucose PET/MRI in Correlation with Histomorphometry and Micro-CT-A Prospective Comparative Study.

OBJECTIVES: The purpose of this study was to investigate the imaging characteristics of medication-related osteonecrosis of the jaw (MRONJ) using [18F]fluoride positron emission tomography/computed tomography (PET/CT) and [18F]fluorodeoxyglucose (FDG) PET/magnetic resonance imaging (MRI) for preoperative assessment and to correlate them with microarchitectural and histomorphometric data with respect to clinical findings. METHODS: Twelve patients (five female; mean age 75 ± 7.6 yr) with symptomatic MRONJ underwent both scans on the same day, and imaging findings were used to plan surgical interventions for seven patients. Bone tracer uptake was classified as high, medium, or low, and surgical samples were evaluated using Micro-CT and histomorphometric analysis. RESULTS: CT showed medullary sclerosis in all patients, and MRI revealed gadolinium enhancement in four patients. PET imaging revealed remarkably elevated [18F]fluoride uptake and moderately increased [18F]FDG uptake in MRONJ compared to healthy jawbones, with both differences being statistically significant. [18F]fluoride uptake was associated with necrosis, bacteria, and inflammatory tissue. Micro-CT data did not show significant differences, but histomorphometric analysis revealed higher osteocyte and lacunae densities in the high [18F]fluoride uptake group, and more necrotic bone in the medium [18F]fluoride uptake group. Bacteria were observed in all areas. CONCLUSIONS: In summary, [18F]fluoride PET accurately identified MRONJ extent, revealing functional changes in jawbone remodeling not visible on CT. [18F]FDG PET showed differences in bone and soft tissue, though less pronounced. This method aids in evaluating disease activity and guiding treatment planning, requiring further research for optimal surgical approaches based on tracer uptake.

Treatment response of advanced HNSCC towards immune checkpoint inhibition is associated with an activated effector memory T cell phenotype.

Locally advanced or metastatic head and neck squamous cell carcinoma (HNSCC) is associated with a poor prognosis. The introduction of PD-1 inhibitors has led to a significant improvement in survival, but only a subpopulation of patients responds to therapy. Current biomarkers cannot reliably identify these patients. The identification of biomarkers for the prediction and monitoring of immunotherapy is therefore of great importance. In this study, we characterized lymphocyte subsets in the peripheral blood of HNSCC patients under PD-1 inhibition. Patients with primary response (n=11) to PD-1 inhibition showed an increase of the CD3+ effector memory (CD3/EM) population and an elevated expression of the activation marker CD69 in CD3+ T cells, particularly in the CD3/EM subpopulation at 3 months when treatment response was assessed. In contrast, patients with primary treatment failure and progressive disease (n=9) despite PD-1 inhibition had lower absolute lymphocyte counts and an increased expression of CTLA-4 in CD3+ T cells at the time of treatment failure compared with baseline, particularly in CD4+ and CD8+ effector memory populations. Our results demonstrate that HNSCC patients' response to immune checkpoint inhibition shows a distinct immune signature in peripheral blood, which could help identify refractory patients earlier. Furthermore, strategies to overcome primary therapy failure by inducing a beneficial T cell phenotype or adding alternative immune checkpoint inhibitors could improve response rates and survival of HNSCC patients.

Prognostic value of histamine H1 receptor expression in oral squamous cell carcinoma.

OBJECTIVES: Overexpression of the histamine H1 receptor (H1R) has been described in a variety of tumor models, but experience in oral squamous cell carcinomas (OSCC) is not available. Current adjuvant treatment options for OSCC can be improved by the identification of new targets of therapy. Herein, we evaluated H1R expression in a large patient cohort of OSCC. MATERIALS AND METHODS: H1R immunoexpression was evaluated in 191 cases of OSCC and two OSCC cell lines BICR56 and BICR3. Scanned images were digitally analyzed using ImageJ and the immunomembrane plug-in. The combined score of computer-assisted semiquantitative analysis was correlated with manually counted percentages of tumor cells by Kendall's tau (т) correlation coefficient. Disease-free survival times were estimated using the Kaplan-Meier method and were compared by using the log-rank test. Multivariate analyses were performed using the Cox proportional hazards model. RESULTS: H1R was rarely expressed in OSCC but significantly related with advanced tumor stages (n = 21/191, mean expression 63.5% of cancer cells in positive tumor samples, 95% confidence interval of the mean 53.5 to 73.6%, p = 0.006). Following univariate analysis, patients with H1R expression showed a significant poorer prognosis (p = 0.0004). Multivariate analysis revealed H1R expression as an independent prognostic factor (p = 0.0164). Expression of H1R in cancer cell lines was confirmed by specific staining of OSCC cell lines BICR56 and BICR3. CONCLUSION: This is the first study focusing on H1R expression showing a significant poorer DFS rate in the H1R+ patient cohort. Based on these data, H1R activation may promote carcinogenesis in OSCC. CLINICAL RELEVANCE: Investigation of H1R regulation and its antagonists shows a clear rationale for future supportive anticancer therapies in OSCCs.

Adjuvant Radiotherapy in Patients with Squamous Cell Carcinoma of the Oral Cavity or Oropharynx and Solitary Ipsilateral Lymph Node Metastasis (pN1)-A Prospective Multicentric Cohort Study.

(1) Background: Evaluation of impact of adjuvant radiation therapy (RT) in patients with oral squamous cell carcinoma of the oral cavity/oropharynx (OSCC) of up to 4 cm (pT1/pT2) and solitary ipsilateral lymph node metastasis (pN1). A non-irradiated group with clinical follow-up was chosen for control, and survival and quality of life (QL) were compared; (2) Methods: This prospective multicentric comprehensive cohort study included patients with resected OSCC (pT1/pT2, pN1, and cM0) who were allocated into adjuvant radiation therapy (RT) or observation. The primary endpoint was overall survival. Secondary endpoints were progression-free survival and QL after surgery; (3) Results: Out of 27 centers, 209 patients were enrolled with a median follow-up of 3.4 years. An amount of 137 patients were in the observation arm, and 72 received adjuvant irradiation. Overall survival did not differ between groups (hazard ratio (HR) 0.98 [0.55-1.73], p = 0.94). There were fewer neck metastases (HR 0.34 [0.15-0.77]; p = 0.01), as well as fewer local recurrences (HR 0.41 [0.19-0.89]; p = 0.02) under adjuvant RT. For QL, irradiated patients showed higher values for the symptom scale pain after 0.5, two, and three years (all p < 0.05). After six months and three years, irradiated patients reported higher symptom burdens (impaired swallowing, speech, as well as teeth-related problems (all p < 0.05)). Patients in the RT group had significantly more problems with mouth opening after six months, one, and two years (p < 0.05); (4) Conclusions: Adjuvant RT in patients with early SCC of the oral cavity and oropharynx does not seem to influence overall survival, but it positively affects progression-free survival. However, irradiated patients report a significantly decreased QL up to three years after therapy compared to the observation group.

[18F]Fluoride Positron-Emission Tomography (PET) and [18F]FDG PET for Assessment of Osteomyelitis of the Jaw in Comparison to Computed Tomography (CT) and Magnetic Resonance Imaging (MRI): A Prospective PET/CT and PET/MRI Pilot Study.

To investigate imaging features of osteomyelitis of the jaw (OMJ) using [18F]fluoride positron emission tomography (PET) and [18F]fluorodeoxyglucose (FDG)-PET compared with computed tomography (CT) and magnetic resonance imaging (MRI) to assess extent and disease activity. Six female patients (55.3 ± 10.0 years) were enrolled for assessment of symptomatic OMJ. 4/6 patients underwent [18F]FDG-PET/MRI and [18F]fluoride-PET/CT, one patient MRI and [18F]fluoride-PET/CT and another patient only [18F]FDG-PET/MRI. Image analysis was performed by two radiologists, an oral and maxillofacial surgeon, and a nuclear medicine specialist. The extent of affected jawbone was analyzed both qualitatively and quantitatively, including the PET tracer uptake, CT-Hounsfield-Units (HU) and MRI parameters in affected and healthy jawbone. All patients had trabecular sclerosis in the affected jawbone compared to healthy jawbone (560 ± 328 HU vs. 282 ± 211 HU; p > 0.05), while 3/6 patients had cortical erosions. Bone marrow edema and gadolinium enhancement were documented in 5/6 patients. In affected jawbone, [18F]fluoride-uptake was increased in all patients compared to healthy jawbone (SUVmean 15.4 ± 4.2 vs. 2.1 ± 0.6; p < 0.05), and [18F]FDG-uptake was moderately higher (SUVmean 1.9 ± 0.7 vs. 0.7 ± 0.2; p > 0.05). The extent of regions with increased metabolic activity was less than the extent of morphologic changes in all patients. Information on jawbone metabolism and inflammation is different from morphologic changes and therefore has the potential to provide a more accurate and objective assessment of the extent and activity of OMJ.

Relevance of a prolonged preoperative antibiotic regime in the treatment of bisphosphonate-related osteonecrosis of the jaw.

PURPOSE: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a severe and therapy-resistant disease. The present study was performed to evaluate the role of the duration of preoperative antibiotic therapy within an otherwise standardized treatment protocol of patients with BRONJ stages I and II. One group of patients received a short-term preoperative antibiotic regime (A-ST) and the other a long-term preoperative antibiotic regime (B-LT). PATIENTS AND METHODS: A retrospective chart review was used to analyze 46 patients with BRONJ from 2004 to 2009 who were treated with the same surgical technique and the same postoperative antibiotic treatment. Ten patients were classified as stage I, and 37 as stage II. All patients had intravenous bisphosphonate therapy in their case histories. Surgical treatment included an extended surgical procedure with sequestrectomy, bone smoothing, tension-free tissue covering, and drainage, with attention to neighboring teeth. After surgery, antibiotics were given (median) for 7 days intravenously and orally for another 10 to 12 days. Only patients who fulfilled these criteria were included in the retrospective chart review. In group A-ST 16 patients with 17 operations received antibiotics for 1 to 8 days before operation, whereas in group B-LT 30 patients had preoperative therapy of 23 to 54 days. Postoperative clinical examination followed a standardized protocol. Complete healing with intact soft tissue coverage was regarded as a success. RESULTS: The mean follow-up in both groups was 17.4 months (median, 11.5 months). Within the overall observation period, only 35% of patients in group A-ST and 70% in group B-LT showed complete healing, but at the time of the last clinical examination, 53% in group A-ST and 87% in group B-LT were free of soft tissue dehiscence. A certain number of soft tissue dehiscences within the observation period could clearly be related to later tooth extractions or pressure sores of dentures; excluding these interfering problems, 47% in group A-ST and 87% in group B-LT were treated successfully. Differences between these groups were significant. CONCLUSIONS: This study indicates that surgical treatment in patients with stage I BRONJ and especially in those with stage II BRONJ in combination with a long-term preoperative antibiotic treatment can lead to a complete healing in 70% to 87% of cases in contrast to 35% to 53% with a short-term regime. The higher success rate after prolonged preoperative antibiotic therapy may be linked to an infectious role in BRONJ etiology requiring adequate treatment. Antibiotics may effectively treat neighboring lightly infected bone, whereas surgery removes the irreversibly infected and necrotic bone. To achieve complete healing, an extended surgical procedure in combination with local mouth rinses and prolonged antibiotic therapy can be recommended for treatment of BRONJ.

18F-Fluoride PET/CT Imaging of Medication-Related Osteonecrosis of the Jaw in Conservative Treatment-A Case Report.

Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect in antiresorptive treatment. Treatment of MRONJ is considered primarily conservative with oral mouth rinses and antibiotics but may demand surgery, depending on the complaints and general condition of the patient, the extent of the necrosis, and the overall prognosis with respect to the underlying disease. A 77 year old female patient with invasive ductal breast cancer and bone metastases was treated with intravenous bisphosphonate (BP) zoledronic acid. During therapy, she developed MRONJ in the mandible with severe pain. Clinical examination revealed confluent exposed bone of the lower left jaw and a fistula at the right molar region. The panoramic radiograph revealed a mandibular osseous involvement with diffuse radiopaque areas between radiolucent areas. For preoperative planning, 18F-fluoride positron emission tomography/computed tomography (PET/CT) of the jaw was performed, showing substantially increased 18F-fluoride uptake in regions 38 to 47 of the mandible with a focal gap in region 36 (area of clinically exposed bone). CT revealed medullary sclerosis and cortical thickening with confluent periosteal reaction and focal cortical erosion in the regions 37 to 42, whereas the regions 43 to 47 were only subtly sclerotic without cortical thickening. After systemic antibiotic therapy with sultamicillin following significant symptom and pain relief, 18F-fluoride PET/CT imaging was performed again after 5 months. No changes in either CT and PET were observed in regions 38 to 42, whereas the bony sclerosis was slightly increased in regions 43 to 47 with a slight reduction of 18F-fluoride uptake. 18F-fluoride PET/CT showed no significant changes assessing the extent of MRONJ prior and after systemic antibiotic therapy, providing no evidence that conservative treatment reduced the extent of the MRONJ-affected jawbone. The additional information of 18F-fluoride PET enables to identify the true extent of MRONJ which may be underestimated by CT imaging alone. Patients with MRONJ undergoing conservative treatment could benefit because additional imaging may be avoided as the pre-therapeutic 18F-fluoride PET/CT delivers all information needed for further treatment. Our findings support the recommendation of a surgical approach as long-term antibiotics cannot downsize the extent of MRONJ.

Microarchitecture of medication-related osteonecrosis of the jaw (MRONJ); a retrospective micro-CT and morphometric analysis.

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (AR) drugs such as bisphosphonates (BP) and denosumab (Dmab). Although several risk factors are described, the etiology of MRONJ is still not fully elucidated. Bone-strengthening is the primary aim of antiresorptive therapy; however, overly increased bone mass and microcrack accumulation are also discussed in MRONJ etiologies. The aim of this study is to evaluate the microarchitecture of jaw bones with micro-computed tomography (micro-CT) in AR-treated patients with or without MRONJ. Human jaw bone samples of AR-treated patients were separated into 11 groups by AR treatment bisphosphonate (BP), denosumab (Dmab), both (M) and control groups. Subgroups were divided according to the clinical localization as AR-exposed vital jaw bone (BPexp, Dmabexp, Mexp), osteonecrosis-margin of a sequestrum (BPOmar, DmabOmar, MOmar) and osteonecrosis-sequestrum (BPOseq, DmabOseq, MOseq). Healthy jaw bone (CHB) and osteoporotic jaw bone (COP) represent control groups. Samples underwent retrospective micro-CT and morphometric analysis in representative units by bone volume fraction (BV/TV), bone surface density (BS/BV), trabecular thickness (Tr.Th.), trabecular number (Tr.N.), trabecular space (Tr.Sp.), Euler characteristic for bone connectivity, bone mineral density (BMD) and tissue mineral density (TMD). A total of 141 samples from 78 patients were analyzed. BV/TV of Mexp group (mean: 0.46 ± 0.27) was significantly higher than in the COP group (mean: 0.14 ± 0.05; p = 0.0053). Tr.Th. differed significantly between the BPexp group (mean: 0.32 ± 0.15) and the Mexp group (mean: 0.57 ± 0.20; p = 0.0452) as well as between the BPOseq group (mean: 0.25 ± 0.10) and the MOseq group (mean: 0.39 ± 0.18; p = 0.0417). Signs of trabecular thickening and unorganized trabecular microarchitecture from AR-exposed- to sequestrum groups, were analyzed in 3D reconstructions. However, BS/BV, Tr.N., and Tr.Sp. showed no significant differences. Euler characteristic of the BPOseq group (median: 7.46) doubled compared to that of the BPexp group (median: 14.97; p = 0.0064). Mineralization parameters BMD and TMD were similar in all groups. Findings show evidence of enhanced bone mass and suspect microarchitecture in some AR-treated jaw bone compared to osteoporotic jaw bone. Despite increased bone mass, some MRONJ samples showed decreased trabecular connectivity by Euler characteristic compared to AR-treated jaw bone. These samples may indicate extensive ossification and ineffective bone mass with superficially higher bone mass without existing or even reduced mechanical stability, indicated by connectivity loss. This result might also suggest a high risk to microcrack accumulation. At some point, possibly some kind of over-ossification could lead to under-nourishment and microarchitectural weakness, creating instability, subsequently increasing vulnerability to MRONJ.

Importance of microcracks in etiology of bisphosphonate-related osteonecrosis of the jaw: a possible pathogenetic model of symptomatic and non-symptomatic osteonecrosis of the jaw based on scanning electron microscopy findings.

The aim of this study was to evaluate a possible role of microcracks in the pathogenesis of bisphosphonate-related osteonecrosis of the jaw (ONJ) and to discuss an etiological model. Bone samples from 35 patients with ONJ were analyzed. Control samples were taken from five patients with osteomyelitis (OM), ten patients with osteoradionecrosis, seven patients with osteoporosis and bisphosphonate medication without signs of ONJ, and six osteoporotic elderly patients. Samples were examined using scanning electron microscopy. In 54% of the bone samples of patients with ONJ, microcracks were seen. Inflammatory and connective tissue reactions within the microcracks were evident in 82% of the cases, indicating that these cracks were not artificial. In contrast, only 29% of samples from patients with oral bisphosphonate medication without ONJ, no sample from patients with OM, none of the osteoradionecrosis group, and only 17% from patients with osteoporosis showed microcracks. Statistically significant differences could be found between the ONJ group and the group after irradiation and the group with OM, respectively. The evidence of microcracks could be a first step in the pathogenesis of bisphosphonate-related ONJ. The accumulation of these microcracks leads to a situation that could be named "non-symptomatic ONJ". Disruptions of the mucosal integrity may then allow bacterial invasion, leading to jawbone infection with exposed bone, fistulas, and pain. This state could be called "symptomatic ONJ". Furthermore, an assumed local immunosuppression as indicated by various studies could explain the severe courses of therapy-resistant ONJ as regularly observed.

Histologic analysis of medication-related osteonecrosis of the jaw compared with antiresorptive-exposed bone and other infectious, inflammatory, and necrotic jaw diseases.

OBJECTIVE: This study characterized histologic features of medication-related osteonecrosis of the jaw (MRONJ) through analysis of tissues from patients and healthy individuals. STUDY DESIGN: Bone biopsies were collected from various infectious, inflammatory, and necrotic jaw diseases. Samples were divided into bone exposed to bisphosphonates or denosumab, as well as bisphosphonate-related osteonecrosis of the jaw (BRONJ), denosumab-related osteonecrosis of the jaw (DRONJ), and mixed necrosis, enabling us to identify features of single agent necrosis without influence from previous therapies. Hematoxylin and eosin (H&E), receptor activator of nuclear factor κ-Β ligand (RANKL), tartrate-resistant acid phosphatase (TRAP), osteoprotegerin, toluidine blue, CD14, and CD68 staining and micro-computed tomography (micro-CT) analysis were performed. Groups were compared by using analysis of variance (ANOVA). RESULTS: In total, 156 bone samples were collected from 105 patients. MRONJ variants exhibited more infectious infiltration. Bisphosphonate (P < .001) and mixed necrosis (P = .002) demonstrated more RANKL- and TRAP-positive osteoclasts. Denosumab necrosis (P = .007), and bone exposed to bisphosphonates (P = .028) in combination with denosumab (P = .022) demonstrated significantly lower numbers of osteocytes per area. CD14 and CD68 positivity was increased for BRONJ (P = .008; P < .001, respectively). MRONJ variants exhibited the widest trabecular width and decreased medullary space to bone. No diminished vascular network in MRONJ samples was observed. CONCLUSIONS: Histologic features differ among MRONJ variants, with oversuppressed bone turnover, dysfunctional bone resorption, and a disturbed osteocyte network as potential mechanisms of pathogenesis.