Beneficial Effect of Metformin on the Five-Year Survival in about 40,000 Patients with Head and Neck Cancer

INTRODUCTION

Even in times of new therapy regimes, the overall survival of patients with head and neck cancer remains low. Since the previous studies showed the beneficial effect of metformin medication on the survival of patients with cancer, our objective was to investigate if-and in which way-metformin medication affects the overall survival of patients with head and neck cancer.

METHODS

Clinical data pertaining to patients diagnosed with head and neck cancer (International Classification of Diseases 10 codes C00-C14, C31, and C32) were retrospectively retrieved from the TriNetX network (TriNetX, Cambridge, MA, USA). The initial cohort extracted from the network was stratified into two groups: patients on metformin medication (cohort I), and individuals not on metformin medication (cohort II). The matching criteria included age, gender, BMI, type 2 diabetes, and risk factors, such as nicotine and alcohol abuse/dependence. Kaplan-Meier analysis, risk analysis, and the calculation of odds and hazard ratios were conducted. Additionally, the Hemoglobin A1c values were subject to analysis.

RESULTS

Following matching, each cohort comprised 20,416 patients. Cohort I exhibited a higher five-year survival rate at 75.3%, in contrast to cohort II, which registered a rate of 69.8%. The odds ratio was 0.79 (95% CI = 0.75-0.83), and the hazard ratio was 0.78 (95% CI = 0.75-0.82).

CONCLUSION

Metformin medication may correlate with improved five-year survival rates in patients with head and neck cancer. Since potentially influencing factors such as comorbidities and the initial tumor stage were not available, the results of our retrospectively conducted study must be interpreted with caution.

Impact of the adjacent bone on pseudarthrosis in mandibular reconstruction with fibula free flaps

BACKGROUND

Mechanical and morphological factors have both been described to influence the rate of pseudarthrosis in mandibular reconstruction. By minimizing mechanical confounders, the present study aims to evaluate the impact of bone origin at the intersegmental gap on osseous union.

METHODS

Patients were screened retrospectively for undergoing multi-segment fibula free flap reconstruction of the mandible including the anterior part of the mandible and osteosynthesis using patient-specific 3D-printed titanium reconstruction plates. Percentage changes in bone volume and width at the bone interface between the fibula/fibula and fibula/mandible at the anterior intersegmental gaps within the same patient were determined using cone-beam computed tomography (CBCT). Additionally, representative samples of the intersegmental zones were assessed histologically and using micro-computed tomography (µCT).

RESULTS

The bone interface (p = 0.223) did not significantly impact the change in bone volume at the intersegmental gap. Radiotherapy (p < 0.001), time between CBCT scans (p = 0.006) and wound healing disorders (p = 0.005) were independent risk factors for osseous non-union. Preliminary analysis of the microstructure of the intersegmental bone did not indicate morphological differences between fibula-fibula and fibula-mandible intersegmental bones.

CONCLUSIONS

The bone interface at the intersegmental gap in mandibular reconstruction did not influence long-term bone healing significantly. Mechanical and clinical properties seem to be more relevant for surgical success.

Comparison of the 3D-microstructure of human alveolar and fibula bone in microvascular autologous bone transplantation: a synchrotron radiation μ-CT study

Introduction: Autologous bone transplantation is successfully used in reconstructive surgery of large/critical-sized bone defects, whereby the microvascular free fibula flap is still regarded as the gold standard for the reconstruction of such defects in the head and neck region. Here, we report the morphological and lacunar properties of patient-paired bone samples from eight patients from the jaw (AB; recipient site) and the fibula (FB; donor site) on the micron length-scale using Synchrotron µ-CT. Insights into differences and similarities between these bone structures could offer a better understanding of the underlying mechanism for successful surgical outcomes and might clear the path for optimized, nature-inspired bone scaffold designs. Methods: Spatial vessel-pore arrangements, bone morphology, fluid-simulation derived permeability tensor, osteocyte lacunar density, and lacunar morphology are compared. Results: The orientation of the vessel system indicates a homogenous vessel orientation for AB and FB. The average mineral distance (50%) to the closest vessel boundary is higher in AB than in FB (the mean is 96 μm for AB vs. 76 μm for FB; p = 0.021). Average osteocyte lacunar density is found to be higher in AB than in FB (mean 22,874 mm3 vs. 19,376 mm3 for FB; p = 0.038), which might compensate for the high distance from the mineral to the nearest vessel. No significant differences in lacunar volume are found between paired AB and FB. Discussion: A comparable vessel network and similar distribution of vessel porosity between AB and FB may allow the FB graft to exhibit a high regeneration potential when connected to AB, and this might correlate with a high osteoinductive and osteoconductive potential of FB when connected to AB. Since widely used and potent synthetic bone grafts exist, new insight into the bone structure of well-established autologous bone grafts, such as the free fibula flap, could help to improve the performance of such materials and therefore the design of 3D scaffolds.

Vestibuloplasty and its impact on the long-term survival and success of dental implants in irradiated and non-irradiated patients after head and neck tumor therapy: a retrospective study

OBJECTIVES

This study aimed to evaluate the influence of vestibuloplasty on the clinical success and survival of dental implants in head and neck tumor patients.

MATERIALS AND METHODS

A retrospective single-center study was conducted. All patients received surgical therapy of a tumor in the head or neck and underwent surgical therapy and, if necessary, radiotherapy/radiochemotherapy. Patients with compromised soft tissue conditions received vestibuloplasty using a split thickness skin graft and an implant-retained splint. Implant survival and success and the influence of vestibuloplasty, gender, radiotherapy, and localizations were evaluated.

RESULTS

A total of 247 dental implants in 49 patients (18 women and 31 men; mean age of 63.6 years) were evaluated. During the observation period, 6 implants were lost. The cumulative survival rate was 99.1% after 1 year and 3 years and 93.1% after 5 years for patients without vestibuloplasty, compared to a survival and success rate of 100% after 5 years in patients with vestibuloplasty. Additionally, patients with vestibuloplasty showed significantly lower peri-implant bone resorption rates after 5 years (mesial: p = 0.003; distal: p = 0.001).

CONCLUSION

This study demonstrates a high cumulative survival and success rate of dental implants after 5 years in head and neck tumor patients, irrespective of irradiation. Patients with vestibuloplasty showed a significantly higher rate of implant survival and significantly lower peri-implant bone resorption after 5 years.

CLINICAL RELEVANCE

Vestibuloplasty should always be considered and applied if required by the anatomical situations to achieve high implant survival/success rates in head and neck tumor patients.

Statin Medication Improves Five-Year Survival Rates in Patients with Head and Neck Cancer: A Retrospective Case-Control Study of about 100,000 Patients

INTRODUCTION

The overall survival among head and neck cancer patients is still low, even in a time of new therapy regimes. Regarding cancer patients' survival, statin use has already proven to be associated with favorable survival outcomes. Our objective was to investigate the influence of statin medication on the overall survival of head and neck cancer patients.

METHODS

Retrospective clinical data of patients diagnosed with head and neck cancer (International Classification of Diseases codes: C00-C14) were retrieved from a real-world evidence database. The initial cohort was divided into patients with statin medication, who were assigned to building cohort I, and subjects without statin medication, who were assigned to cohort II, both matched by age, gender, and risk factors (nicotine and alcohol abuse/dependence). Subsequently, Kaplan-Meier and risk analyses were performed, and odds and hazard ratios were calculated.

RESULTS

After matching, each cohort contained 48,626 patients (cohort I = females: 15,409; (31.7%), males 33,212 (68.3%); mean age ± standard deviation (SD) at diagnosis 66.3 ± 11.4 years; cohort II = females: 15,432; (31.7%), males 33,187 (68.2%); mean age ± standard deviation (SD) at diagnosis 66.4 ± 11.5 years). Five-year survival was found to be significantly higher for cohort I, with 75.19%, respectively 70.48% for cohort II. These findings were correlated significantly with a risk of death of 15.9% (cohort I) and 17.2% (cohort II); the odds ratio was 0.91 (95% CI: 0.881-0.942) and the hazard ratio 0.80 (0.777-0.827).

CONCLUSIONS

The results indicate that the five-year survival of head and neck cancer patients is significantly improved by statin medication. As this study was conducted retrospectively, our data must be interpreted with caution, especially since other potential influencing factors and the initial tumor stage were not available.

Comparison of the 3D-Microstructure Between Alveolar and Iliac Bone for Enhanced Bioinspired Bone Graft Substitutes

In oral- and maxillofacial bone augmentation surgery, non-vascularized grafts from the iliac crest demonstrate better clinical performance than alveolar bone grafts. The underlying mechanisms are not fully understood but are essential for the enhancement of bone regeneration scaffolds. Synchrotron Radiation µ-CT at a pixel size of 2.3 μm was used to characterize the gross morphology and the vascular and osteocyte lacuna porosity of patient-matched iliac crest/alveolar bone samples. The results suggest a difference in the spatial distribution of the vascular pore system. Fluid simulations reveal the permeability tensor to be more homogeneous in the iliac crest, indicating a more unidirectional fluid flow in alveolar bone. The average distance between bone mineral and the closest vessel pore boundary was found to be higher in alveolar bone. At the same time, osteocyte lacunae density is higher in alveolar bone, potentially compensating for the longer average distance between the bone mineral and vessel pores. The present study comprehensively quantified and compared the 3D microarchitecture of intraindividual human alveolar and iliac bone. The identified difference in pore network architecture may allow a bone graft from the iliac crest to exhibit higher regeneration potential due to an increased capacity to connect with the surrounding pore network of the residual bone. The results may contribute to understanding the difference in clinical performance when used as bone grafts and are essential for optimization of future scaffold materials.

Epidemiology, Injury Severity, and Pattern of Standing E-Scooter Accidents: 6-Month Experience from a German Level I Trauma Center

Background

E-scooter usage was lawfully approved in Germany in June 2019. Since then, a marked increase of e-scooter drivers has been noticed. Evidence concerning factors that may affect the severity of these injuries is limited. The study aimed to retrospectively analyze e-scooter-related injuries in a major German city.

Methods

All patients admitted to the emergency department of a level I trauma center in Berlin, Germany, between June 15, 2019, and December 15, 2019, were retrospectively reviewed. Patients involved in an e-scooter accident were included in this study, and medical reports were analyzed.

Results

In the study period, 43 patients were involved in an e-scooter accident and could be included in this study. The median age of the patients was 30 years (interquartile range [IQR], 24.50–39.50 years), with 19 (44.2%) being female patients. The median Injury Severity Score of all patients was 2.0, with the highest Abbreviated Injury Scale (AIS) of 3.00 (IQR, 2.00–3.00) and was recorded as thoracic injuries. Seven patients had extremity fractures, of which 4 had to be stabilized operatively. In 12 patients (27.9%), the accidents occurred under the influence of alcohol.

Conclusions

The majority of injuries reported in this study were associated with a relatively low AIS, possibly due to strict local speed limits. Nonetheless, e-scooter usage bears risks of sustaining severe injuries to the head, face, and extremities, particularly under the influence of alcohol or when illegally ignoring local laws.

Imaging foreign bodies in head and neck trauma: a pictorial review

Open injuries bear the risk of foreign body contamination. Commonly encountered materials include gravel debris, glass fragments, wooden splinters or metal particles. While foreign body incorporation is obvious in some injury patterns, other injuries may not display hints of being contaminated with foreign body materials. Foreign objects that have not been detected and removed bear the risk of leading to severe wound infections and chronic wound healing disorders. Besides these severe health issues, medicolegal consequences should be considered. While an accurate clinical examination is the first step for the detection of foreign body materials, choosing the appropriate radiological imaging is decisive for the detection or non-detection of the foreign material. Especially in cases of impaired wound healing over time, the existence of an undetected foreign object needs to be considered.

Here, we would like to give a practical radiological guide for the assessment of foreign objects in head and neck injuries by a special selection of patients with different injury patterns and various foreign body materials with regard to the present literature.

Impact of the Rising Number of Rentable E-scooter Accidents on Emergency Care in Berlin 6 Months After the Introduction: A Maxillofacial Perspective

Study Design

Retrospective study of all patients presented at our emergency department after an accident while riding an e-scooter between 15 June 2019 and 15 December 2019. Out of this group, we subgrouped all patients with injuries to the head and neck area.

Objective

Shared e-scooter systems have recently been introduced in many big cities worldwide and are becoming increasingly popular. This retrospective study aimed to give a detailed overview of clinical data on consequences of e-scooter accidents, with particular attention to the maxillofacial point of view.

Methods

We performed a single-center retrospective study of all patients presented at our emergency department after an accident while riding an e-scooter between June 15, 2019 and December 15, 2019.

Results

Within the observation period, 43 patients (mean age of 32 years; range: 17-64 years) suffered from an accident while riding an e-scooter. Of these, 25 patients (58%) required maxillofacial treatment whereby 9 patients (36%) suffered a fracture (56% fracture of the mandible; 33% fracture of the nasal bone; 11% fracture of the maxilla). Six patients required maxillofacial surgical treatment. Twelve patients (28%) stated to have been driving under the influence of alcohol at the time of the accident (blood alcohol level between 0.77 g/L and 2.32 g/L). None of the patients used body protection, and only one patient wore a helmet (2%).

Conclusions

With the introduction of shared e-scooter systems, health-care facilities are faced with an increasing number of accidents related to the use of e-scooters, suffering from a high percentage of injuries in the maxillofacial region. Facial injuries might be reduced by the mandatory use of a helmet with faceguard. The trauma mechanism, in particular, seems to differ from other common trauma cases and needs to be examined more closely.

A study of complaints and their relation to vertebral destruction in patients with osteoporosis

Patients with spinal osteoporosis suffer from vertebral deformation, loss of height and back pain, as well as from functional limitations and alterations of mood. So far little is known about the extent of these clinical symptoms at all and whether they are related in a predictable manner to the fractures or damages of bone structure. In the present study we investigated the relation between vertebral deformation and clinical symptoms in 70 patients with osteoporosis. Clinical data like pain, functional limitations and parameters of mood were examined by a standardized questionnaire. The numbers of vertebral fractures were determined, and the vertebral destruction was quantified using the Spine Deformity Index (SDI). The symptoms and functional limitations were graded and correlated to the SDI and the number of fractures. Our results underline a relation between the extent of vertebral deformation and the reduction in quality of life by pain, functional limitations and alterations of mood. This relationship was absent or less evident, if the number of fractures was taken into account. Besides the difficulties concerning the grading and quantification of clinical symptoms and outcome of disease, our study revealed that there is a causal relation between the extent of vertebral destruction measured by the SDI and the extent of these clinical parameters.