From the Oral Cavity to the Spine: Prevalence of Oral Cavity Infections in Patients with Pyogenic Spinal Infection.

Background incidence of pyogenic spinal infections has increased in recent years. In addition to treating the spinal infection, optimal care also includes identifying the source of the pyogenic spinal infection and the presence of other infections. The aim of this study is to elucidate the prevalence of oral cavity infection (OCI) within this patient cohort. Methods As part of a prospective study conducted from 2016 to 2021, the number of patients with dental infections was investigated by means of an orthopantomogram (OPG) and subsequent dental examination. Results The presence of an oral infection was investigated in 55 (47%) of 118 patients by an OPG, 29 (53%) of whom had a corresponding abnormality of the oral cavity. In addition to the spinal infection, patients with an oral cavity infection revealed an increased incidence of endocarditis, sepsis and brain abscess. A spinal epidural abscess, a multilevel affection of the infection, and an elevated CRP value were also found in patients with a co-existing oral cavity infection. Back pain assessed at admission and 3 months after surgery was also more pronounced in patients with an oral cavity infection. Neurological deficits were often present in patients with spinal and oral cavity infection. Conclusions The presence of an oral cavity infection has proven to be one of the important factors in the detection of the source of the pyogenic spinal infection. In addition, a pronounced spinal affection and frequent co-infections were seen in patients with an oral cavity infection.

Extent of Neck Dissection and Cervical Lymph Node Involvement in Oral Squamous Cell Carcinoma.

Introduction: Tumor resection combined with neck dissection (ND) or radiotherapy are established methods for the treatment of patients with oral squamous cell carcinoma (OSCC). However, the extent of ND can lead to postoperative complications. Therefore, for the first time, this study aims to identify lymph node involvement in OSCC performed in a bilateral systematic approach based on oncologic board meetings relying on presurgical magnetic resonance imaging (MRI) and computed tomography (CT). Materials and Methods: In a retrospective single-center study, patients with primary OSCC resection and systematic ND performed in 4 different manners (MRND III bilateral, MRND III left and SND right, MRND III right, SND left, and SND bilateral) were examined. Lymph node involvement allocated to levels was evaluated depending on primary localization and T-stage. Results: A total of 177 consecutive patients (mean age 63.64; 92 female, male 85) were enrolled in this study. A total of 38.98% showed cervical lymph node involvement, and metastases were found in levels 1-4. The distribution of positive lymph node metastases (n=190 LNs) was 39.47% in level 1, 38.95% in level 2, 10.53% in level 3, and 11.05% in level 4. Discussion: In a cohort of OSCC patients with systematic bilateral ND, levels 1 and 2 had positive lymph node involvement, and no lymph node involvement was seen at level 5. Without any clinical or imaging suspicion, ND expanding 5-level MRND should be avoided regardless of the primary tumor localization, T-stage and intraoperative proof of cervical metastases.

Neoadjuvant Chemoradiotherapy for Oral Cavity Cancer: Predictive Factors for Response and Interim Analysis of the Prospective INVERT-Trial.

Background: To study neoadjuvant chemoradiotherapy (nCRT) and potential predictive factors for response in locally advanced oral cavity cancer (LA-OCC). Methods: The INVERT trial is an ongoing single-center, prospective phase 2, proof-of-principle trial. Operable patients with stage III-IVA squamous cell carcinomas of the oral cavity were eligible and received nCRT consisting of 60 Gy with concomitant cisplatin and 5-fluorouracil. Surgery was scheduled 6-8 weeks after completion of nCRT. Explorative, multiplex immunohistochemistry (IHC) was performed on pretreatment tumor specimen, and diffusion-weighted magnetic resonance imaging (DW-MRI) was conducted prior to, during nCRT (day 15), and before surgery to identify potential predictive biomarkers and imaging features. Primary endpoint was the pathological complete response (pCR) rate. Results: Seventeen patients with stage IVA OCC were included in this interim analysis. All patients completed nCRT. One patient died from pneumonia 10 weeks after nCRT before surgery. Complete tumor resection (R0) was achieved in 16/17 patients, of whom 7 (41%, 95% CI: 18-67%) showed pCR. According to the Clavien-Dindo classification, grade 3a and 3b complications were found in 4 (25%) and 5 (31%) patients, respectively; grade 4-5 complications did not occur. Increased changes in the apparent diffusion coefficient signal intensities between MRI at day 15 of nCRT and before surgery were associated with better response (p=0.022). Higher abundances of programmed cell death protein 1 (PD1) positive cytotoxic T-cells (p=0.012), PD1+ macrophages (p=0.046), and cancer-associated fibroblasts (CAFs, p=0.036) were associated with incomplete response to nCRT. Conclusion: nCRT for LA-OCC followed by radical surgery is feasible and shows high response rates. Larger patient cohorts from randomized trials are needed to further investigate nCRT and predictive biomarkers such as changes in DW-MRI signal intensities, tumor infiltrating immune cells, and CAFs.

Multinucleated giant cells within the in vivo implantation bed of a collagen-based biomaterial determine its degradation pattern.

OBJECTIVES: The aim of the present study was to characterize the cellular reaction to a xenogeneic resorbable collagen membrane of porcine origin using a subcutaneous implantation model in Wistar rats over 30 days. MATERIALS AND METHODS: Ex vivo, liquid platelet-rich fibrin (PRF), a leukocyte and platelet-rich cell suspension, was used to evaluate the blood cell membrane interaction. The material was implanted subcutaneously in rats. Sham-operated rats without biomaterial displayed physiological wound healing (control group). Histological, immunohistological, and histomorphometric analyses were focused on the inflammatory pattern, vascularization rate, and degradation pattern. RESULTS: The membrane induced a large number of mononuclear cells over the observation period, including lymphocytes, macrophages, and fibroblasts. After 15 days, multinucleated giant cells (MNGCs) were observed on the biomaterial surface. Their number increased significantly, and they proceeded to the center of the biomaterial on day 30. These cells highly expressed CD-68, calcitonin receptor, and MMP-9, but not TRAP or integrin-ß3. Thus, the membrane lost its integrity and underwent disintegration as a consequence of the induction of MNGCs. The significant increase in MNGC number correlated with a high rate of vascularization, which was significantly higher than the control group. Physiological wound healing in the control group did not induce any MNGCs at any time point. Ex vivo blood cells from liquid-PRF did not penetrate the membrane. CONCLUSION: The present study suggests a potential role for MNGCs in biomaterial degradation and questions whether it is beneficial to accept them in clinically approved biomaterials or focus on biomaterials that induce only mononuclear cells. Thus, further studies are necessary to identify the function of biomaterial-induced MNGCs. CLINICAL RELEVANCE: Understanding the cellular reaction to biomaterials is essential to assess their suitability for specific clinical indications and outline the potential benefit of specific group of biomaterials in the respective clinical indications.