FADD amplification is associated with CD8+ T-cell exclusion and malignant progression in HNSCC.

OBJECTIVE: This study aimed to clarify the relationship between FADD amplification and overexpression and the tumor immune microenvironment. METHODS: Immunohistochemical staining and bioanalysis were used to analyze the association between FADD expression in tumor cells and cells in tumor microenvironment. RNA-seq analysis was used to detect the differences in gene expression upon FADD overexpression. Flow cytometry and multicolor immunofluorescence staining (mIHC) were used to detect the differences in CD8+ T-cell infiltration in FADD-overexpressed cells or tumor tissues. RESULTS: Overexpression of FADD significantly promoted tumor growth. Cells with high FADD expression presented high expression of CD276 and FGFBP1 and low expression of proinflammatory factors (such as IFIT1-3 and CXCL8), which reduced the percentage of CD8+ T cells and created a "cold tumor" immune microenvironment, thus promoting tumor progression. In vivo and in vitro experiment confirmed that tumor tissues with excessive FADD expression exhibited CD8+ T-cell exclusion in the microenvironment. CONCLUSION: Our preliminary investigation has discovered the association between FADD expression and the immunosuppressive microenvironment in HNSCC. Due to the high frequent amplification of the chromosomal region 11q13.3, where FADD is located, targeting FADD holds promise for improving the immune-inactive state of tumors, subsequently inhibiting HNSCC tumor progression.

Single-cell analyses reveal the metabolic heterogeneity and plasticity of the tumor microenvironment during head and neck squamous cell carcinoma progression.

Metabolic reprogramming is a hallmark of cancer. In addition to metabolic alterations in the tumor cells, multiple other metabolically active cell types in the tumor microenvironment (TME) contribute to the emergence of a tumor-specific metabolic milieu. Here, we defined the metabolic landscape of the TME during progression of head and neck squamous cell carcinoma (HNSCC) by performing single-cell RNA sequencing (scRNA-seq) on 26 human patient specimens, including normal tissue, pre-cancerous lesions, early-stage cancer, advanced-stage cancer, lymph node metastases, and recurrent tumors. The analysis revealed substantial heterogeneity at the transcriptional, developmental, metabolic, and functional levels in different cell types. SPP1+ macrophages were identified as a pro-tumor and pro-metastatic macrophage subtype with high fructose and mannose metabolism, which was further substantiated by integrative analysis and validation experiments. An inhibitor of fructose metabolism reduced the proportion of SPP1+ macrophages, reshaped the immunosuppressive TME, and suppressed tumor growth. In conclusion, this work delineated the metabolic landscape of HNSCC at a single-cell resolution and identified fructose metabolism as a key metabolic feature of a pro-tumor macrophage subpopulation.

Hydrogen Therapy Reverses Cancer-Associated Fibroblasts Phenotypes and Remodels Stromal Microenvironment to Stimulate Systematic Anti-Tumor Immunity.

Tumor microenvironment (TME) plays an important role in the tumor progression. Among TME components, cancer-associated fibroblasts (CAFs) show multiple tumor-promoting effects and can induce tumor immune evasion and drug-resistance. Regulating CAFs can be a potential strategy to augment systemic anti-tumor immunity. Here, the study observes that hydrogen treatment can alleviate intracellular reactive oxygen species of CAFs and reshape CAFs' tumor-promoting and immune-suppressive phenotypes. Accordingly, a controllable and TME-responsive hydrogen therapy based on a CaCO3 nanoparticles-coated magnesium system (Mg-CaCO3) is developed. The hydrogen therapy by Mg-CaCO3 can not only directly kill tumor cells, but also inhibit pro-tumor and immune suppressive factors in CAFs, and thus augment immune activities of CD4+ T cells. As implanted in situ, Mg-CaCO3 can significantly suppress tumor growth, turn the "cold" primary tumor into "hot", and stimulate systematic anti-tumor immunity, which is confirmed by the bilateral tumor transplantation models of "cold tumor" (4T1 cells) and "hot tumor" (MC38 cells). This hydrogen therapy system reverses immune suppressive phenotypes of CAFs, thus providing a systematic anti-tumor immune stimulating strategy by remodeling tumor stromal microenvironment.

Radiation-induced fibrosis: Mechanisms and therapeutic strategies from an immune microenvironment perspective.

Radiation-induced fibrosis (RIF) is a severe chronic complication of radiotherapy (RT) manifested by excessive extracellular matrix (ECM) components deposition within the irradiated area. The lung, heart, skin, jaw, pelvic organs and so on may be affected by RIF, which hampers body functions and quality of life. There is accumulating evidence suggesting that the immune microenvironment may play a key regulatory role in RIF. This article discussed the synergetic or antagonistic effects of immune cells and mediators in regulating RIF's development. Several potential preventative and therapeutic strategies for RIF were proposed based on the immunological mechanisms to provide clinicians with improved cognition and clinical treatment guidance.

FUT8-mediated aberrant N-glycosylation of SEMA7A promotes head and neck squamous cell carcinoma progression.

SEMA7A belongs to the Semaphorin family and is involved in the oncogenesis and tumor progression. Aberrant glycosylation has been intricately linked with immune escape and tumor growth. SEMA7A is a highly glycosylated protein with five glycosylated sites. The underlying mechanisms of SEMA7A glycosylation and its contribution to immunosuppression and tumorigenesis are unclear. Here, we identify overexpression and aberrant N-glycosylation of SEMA7A in head and neck squamous cell carcinoma, and elucidate fucosyltransferase FUT8 catalyzes aberrant core fucosylation in SEMA7A at N-linked oligosaccharides (Asn 105, 157, 258, 330, and 602) via a direct protein‒protein interaction. A glycosylated statue of SEMA7A is necessary for its intra-cellular trafficking from the cytoplasm to the cytomembrane. Cytokine EGF triggers SEMA7A N-glycosylation through increasing the binding affinity of SEMA7A toward FUT8, whereas TGF-ß1 promotes abnormal glycosylation of SEMA7A via induction of epithelial-mesenchymal transition. Aberrant N-glycosylation of SEMA7A leads to the differentiation of CD8+ T cells along a trajectory toward an exhausted state, thus shaping an immunosuppressive microenvironment and being resistant immunogenic cell death. Deglycosylation of SEMA7A significantly improves the clinical outcome of EGFR-targeted and anti-PD-L1-based immunotherapy. Finally, we also define RBM4, a splice regulator, as a downstream effector of glycosylated SEMA7A and a pivotal mediator of PD-L1 alternative splicing. These findings suggest that targeting FUT8-SEMA7A axis might be a promising strategy for improving antitumor responses in head and neck squamous cell carcinoma patients.

Macrophage heterogeneity and its interactions with stromal cells in tumour microenvironment.

Macrophages and tumour stroma cells account for the main cellular components in the tumour microenvironment (TME). Current advancements in single-cell analysis have revolutionized our understanding of macrophage diversity and macrophage-stroma interactions. Accordingly, this review describes new insight into tumour-associated macrophage (TAM) heterogeneity in terms of tumour type, phenotype, metabolism, and spatial distribution and presents the association between these factors and TAM functional states. Meanwhile, we focus on the immunomodulatory feature of TAMs and highlight the tumour-promoting effect of macrophage-tumour stroma interactions in the immunosuppressive TME. Finally, we summarize recent studies investigating macrophage-targeted therapy and discuss their therapeutic potential in improving immunotherapy by alleviating immunosuppression.

Enhanced tissue infiltration and bone regeneration through spatiotemporal delivery of bioactive factors from polyelectrolytes modified biomimetic scaffold.

Efficient healing of bone defect is closely associated with the structured and functional characters of tissue engineered scaffolds. However, the development of bone implants with rapid tissue ingrowth and favorable osteoinductive properties remains a challenge. Herein, we fabricated polyelectrolytes modified-biomimetic scaffold with macroporous and nanofibrous structures as well as simultaneous delivery of BMP-2 protein and trace element strontium. The hierarchically structured scaffold incorporated with strontium-substituted hydroxyapatite (SrHA) was coated with polyelectrolyte multilayers of chitosan/gelatin via layer-by-layer assembly technique for BMP-2 immobilization, which endowed the composite scaffold with sequential release of BMP-2 and Sr ions. The integration of SrHA improved the mechanical property of composite scaffold, while the polyelectrolytes modification strongly increased the hydrophilicity and protein binding efficiency. In addition, polyelectrolytes modified-scaffold significantly facilitated cell proliferation in vitro, as well as enhanced tissue infiltration and new microvascular formation in vivo. Furthermore, the dual-factor loaded scaffold significantly enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells. Moreover, both vascularization and new bone formation were significantly increased by the treatment of dual-factor delivery scaffold in the rat calvarial defects model, suggesting a synergistic effect on bone regeneration through spatiotemporal delivery of BMP-2 and Sr ions. Overall, this study demonstrate that the prepared biomimetic scaffold as dual-factor delivery system has great potential for bone regeneration application.

Lipid metabolism marker CD36 is associated with 18FDG-PET/CT false negative lymph nodes in head and neck squamous cell carcinoma.

Background: Lymph node metastasis frequently occurs in head and neck squamous cell carcinoma (HNSCC) patients, and [18F] fluorodeoxyglucose positron emission tomography with computed tomography (18FDG-PET/CT) examination for lymph node metastasis could result in false negativity and delay following treatment. However, the mechanism and resolution for 18FDG-PET/CT false negatives remain unclear. Our study was aim to found biomarkers for false negativity and true positivity from a metabolic perspective. Methods: Ninety-two patients diagnosed with HNSCC who underwent preoperative 18FDG-PET/CT and subsequent surgery in our institution were reviewed. Immunohistochemistry (IHC) examinations of glucose metabolism (GLUT1 and GLUT5), amino acid metabolism4 (GLS and SLC1A5), and lipid metabolism (CPT1A and CD36) markers were conducted on their primary lesion and lymph node sections. Results: We identified specific metabolic patterns of the false-negative group. Significantly, CD36 IHC score of primary lesions was higher in false-negative group than true-positive group. Moreover, we validated pro-invasive biological effects of CD36 by bioinformatics analysis as well as experiments. Conclusion: IHC examination of CD36 expression, which is a lipid metabolism marker, in primary lesions could distinguish HNSCC patients' lymph nodes false negatives in 18FDG-PET/CT.

Immune microenvironment: novel perspectives on bone regeneration disorder in osteoradionecrosis of the jaws.

Osteoradionecrosis of the jaws (ORNJ) is a severe complication that occurs after radiotherapy of head and neck malignancies. Clinically, conservative treatments and surgeries for ORNJ exhibited certain therapeutic effects, whereas the regenerative disorder of the post-radiation jaw remains a pending problem to be solved. In recent years, the recognition of the role of the immune microenvironment has led to a shift from an osteoblasts (OBs) or bone marrow mesenchymal stromal cells (BMSCs)-centered view of bone regeneration to the concept of a complicated microecosystem that supports bone regeneration. Current advances in osteoimmunology have uncovered novel targets within the immune microenvironment to help improve various regeneration therapies, notably therapies potentiating the interaction between BMSCs and immune cells. However, these researches lack a thorough understanding of the immune microenvironment and the interaction network of immune cells in the course of bone regeneration, especially for the post-operative defect of ORNJ. This review summarized the composition of the immune microenvironment during bone regeneration, how the immune microenvironment interacts with the skeletal system, and discussed existing and potential strategies aimed at targeting cellular and molecular immune microenvironment components.

Intratumoral tertiary lymphoid structures promote patient survival and immunotherapy response in head neck squamous cell carcinoma.

Tertiary lymphoid structures (TLSs) hold the potential role in the prediction of immunotherapy response in several clinical trials. TLSs in head neck squamous cell carcinoma (HNSCC) have been investigated through IHC analysis, whereas there is no TLS gene signature to evaluate the level of TLS neogenesis. We here proposed a TLS signature containing 13 chemokines and determined TLS-hi and TLS-low groups in HNSCC samples from The Cancer Genome Atlas. TLS-hi condition signified a better overall survival. A more inflamed immune infiltrative landscape was identified in the TLS-hi tumors characterized by higher proportion of T cells, TCR/BCR activation and antigen processing. High level of TLSs has a determined role in the clinical significance of T cells. Interesting discovery was that innate lymphoid cells and cancer-associated fibroblasts were positively associated with TLS neogenesis in TME of HNSCC. Furthermore, by integrated TLSs with stromal cells and score, immune cells and score, TMB and malignant cells, we proposed a novel HNSCC TME classifications (HNSCC-TCs 1-5), unravelling the counteracted role of stromal cells and score in inflamed immune landscape, which may provide a novel stromal targeted modality in HNSCC therapy. Finally, we verified that TLS statue is an ideal predictor for immune checkpoint blockade immunotherapy. Current study indicated that the TLSs serve as a novel prognostic biomarker and predictor for immunotherapy, which may provide directions to the current investigations on immunotherapeutic strategies for HNSCC.

Constrast-enhanced computed tomography radiomics predicts CD27 expression and clinical prognosis in head and neck squamous cell carcinoma.

Objective: This study aimed to construct a radiomics model that predicts the expression level of CD27 in patients with head and neck squamous cell carcinoma (HNSCC). Materials and methods: Genomic data and contrast-enhanced computed tomography (CT) images of patients with HNSCC were downloaded from the Cancer Genome Atlas and Cancer Imaging Archive for prognosis analysis, image feature extraction, and model construction. We explored the potential molecular mechanisms underlying CD27 expression and its relationship with the immune microenvironment and predicted CD27 mRNA expression in HNSCC tissues. Using non-invasive, CT-based radiomics technology, we generated a radiomics model and evaluated its correlation with the related genes and HNSCC prognosis. Results and conclusion: The expression level of CD27 in HNSCC may significantly influence the prognosis of patients with HNSCC. Radiomics based on contrast-enhanced CT is potentially effective in predicting the expression level of CD27.

A Sonication-Activated Valence-Variable Sono-Sensitizer/Catalyst for Autography Inhibition/Ferroptosis-Induced Tumor Nanotherapy.

The effective deployment of reactive oxygen species (ROS)-mediated oncotherapy in practice remains challenging, mired by uncontrollable catalytic processes, stern reaction conditions and safety concerns. Herein, we develop a copper nanodot integrating sonodynamic and catalytic effects within one active center, which responds to exogenous ultrasound (US) and endogenous H2 O2 stimuli. US irradiation induces the valence conversion from CuII to CuI catalyzing H2 O2 into ⋅OH for chemodynamic therapy. Meanwhile, valence transformation results in electron-hole pairs separation, promoting ROS generation for sonodynamic therapy. Notably, copper nanodots not only block lysosome fusion and degradation leading to autophagy flux blockage, but also interfere with the glutathione peroxidase 4 and cystine-glutamate antiporter SLC7A11 function achieving ferroptosis. Furthermore, reversible valence changes, inherent hydrophilicity and renal clearance ultrasmall size guarantee biosafety.

Plac1 Remodels the Tumor Immune Evasion Microenvironment and Predicts Therapeutic Response in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC or HNSC) is the sixth most common cancer worldwide. Placenta-specific 1 (Plac1) belongs to the cancer testis antigen family and is highly expressed in malignant cells in HNSC. However, the biological function and prognostic value of plac1 in HNSC are still unclear. In the current research, we performed a comprehensive analysis of plac1 using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) bulk RNA sequencing databases as well as a single-cell sequencing dataset. We constructed a 15-gene prognostic signature through screening plac1-related immunomodulators and validated its efficiency and accuracy in immunotherapy cohorts and a pancancer database. We found that plac1 expression level is a prognostic predictor of poor overall survival in patients with HNSC. Plac1 is associated with epithelial-mesenchymal transition and tumor invasion. Plac1 has a "dual immunosuppressive function" on tumor microenvironment. On one hand, plac1-positive cells promote extracellular matrix formation and suppress immune cell infiltration. On the other hand, plac1-positive cells enhance the interaction between dendritic cells and macrophages, which further suppresses antitumor immunity. Finally, we constructed a 15-gene prognostic signature, the efficiency and accuracy of which were validated in immunotherapy cohorts and a pancancer database. In conclusion, plac1 is a promising candidate biomarker for prognosis, a potential target for immunotherapy, and a novel point for studying the immunosuppressive mechanisms of the tumor microenvironment in HNSC.

A nonferrous ferroptosis-like strategy for antioxidant inhibition-synergized nanocatalytic tumor therapeutics.

Ferroptosis, an emerging type of cell death found in the past decades, features specifically lipid peroxidation during the cell death process commonly by iron accumulation. Unfortunately, however, the direct delivery of iron species may trigger undesired detrimental effects such as anaphylactic reactions in normal tissues. Up to date, reports on the cellular ferroptosis by using nonferrous metal elements can be rarely found. In this work, we propose a nonferrous ferroptosis-like strategy based on hybrid CoMoO4-phosphomolybdic acid nanosheet (CPMNS)­enabled lipid peroxide (LOOH) accumulation via accelerated Mo(V)-Mo(VI) transition, elevated GSH depletion for GPX4 enzyme deactivation, and ROS burst, for efficient ferroptosis and chemotherapy. Both in vitro and in vivo outcomes demonstrate the notable anticancer ferroptosis efficacy, suggesting the high feasibility of this CPMNS-enabled ferroptosis-like therapeutic concept. It is highly expected that such ferroptosis-like design in nanocatalytic medicine would be beneficial to future advances in the field of cancer-therapeutic regimens.

Salvage surgery for patients with residual/persistent diseases after improper or insufficient treatment of oral squamous cell carcinoma: can we rectify these mistakes?

BACKGROUND: Patterns of failure after treatment of oral and squamous cell carcinomas (OSCC) are diversified, with recurrences being one of the common causes. A special group of patients are sometimes encountered in the outpatient clinic for improper or insufficient initial treatment with reports of positive margins, implying residual/persistent diseases. The question of whether these patients can be surgically salvaged remain unanswered. METHODS: A retrospective study was performed between January 2013 and December 2017 for patients with residual or rapid recurrent (within 3 months) OSCCs, who received salvage surgeries in our institution. The patients with residual/persistent OSCCs were those with microscopic or macroscopic positive surgical margins, while those with rapid recurrent OSCCs were those with close or negative margins, but unabated painful symptoms right after treatment. Both clinicopathological and prognostic variables were analyzed. The focus was also directed towards lessons for possible initial mistakes, resulting in these residual/persistent diseases. RESULTS: Of 103 patients, 68 (66%) were men, with mean age of 56.3 years. The overall survival reached 60.2%. Regarding the primary OSCC status, most of our patients (n = 75, 72.8%) were diagnosed with ycT2-3 stages. Besides, most patients were found with macroscopic residual diseases (52.4%) before our salvage surgery. The sizes of the residual/persistent OSCCs were generally under 4 cm (87.3%) with minimally residual in 21 (20.4%). Among all the variables, primary T stage (p = 0.003), and residual lesion size (p < 0.001) were significantly associated with the prognosis in multivariate analysis. Though the causes for the initial surgical failure were multifactorial, most were stemmed from poor planning and unstandardized execution. CONCLUSIONS: Cases with residual/persistent OSCCs were mostly due to mistakes which could have been avoided under well-round treatment plans and careful surgical practice. Salvage surgery for cases with smaller residual/persistent OSCCs is still feasible with acceptable outcomes.

A novel era of cancer/testis antigen in cancer immunotherapy.

Immunotherapy is a regimen that is especially utilized in many advanced cancers. Tumor antigens include tumor-specific antigens and tumor-associated antigens, and they function as targets for immunotherapy, such as cancer vaccines and autologous T cells. Cancer/testis antigens (CTAs), which is a group of genes that are restrictedly expressed in malignant cells as well as some germline cells, are tumor-associated antigens. These expression characteristics make CTAs promising candidates for vaccine or T cell therapy targets. Cancer vaccines utilize cancer antigens to induce specific cellular and humoral immune responses to strengthen the body's immune system. T cell transfer therapy refers to genetically modifying T cells to express antigen-specific T cell receptors or chimeric antigen receptors, both of which can be directly activated by tumor antigens. Moreover, combined therapies are being investigated based on CTAs. Current studies have mainly focused on MAGE-A, NY-ESO-1, and IL-13Rα. And we will review clinical trials of CTA-based immunotherapies related to these three antigens. We will summarize completed trials and results and examine the future trends in immunotherapy.

Macrophage migration inhibitory factor regulates joint capsule fibrosis by promoting TGF-ß1 production in fibroblasts.

Joint capsule fibrosis caused by excessive inflammation results in post-traumatic joint contracture (PTJC). Transforming growth factor (TGF)-ß1 plays a key role in PTJC by regulating fibroblast functions, however, cytokine-induced TGF-ß1 expression in specific cell types remains poorly characterized. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine involved in inflammation- and fibrosis-associated pathophysiology. In this study, we investigated whether MIF can facilitate TGF-ß1 production from fibroblasts and regulate joint capsule fibrosis following PTJC. Our data demonstrated that MIF and TGF-ß1 significantly increased in fibroblasts of injured rat posterior joint capsules. Treatment the lesion sites with MIF inhibitor 4-Iodo-6-phenylpyrimidine (4-IPP) reduced TGF-ß1 production and relieved joint capsule inflammation and fibrosis. In vitro, MIF facilitated TGF-ß1 expression in primary joint capsule fibroblasts by activating mitogen-activated protein kinase (MAPK) (P38, ERK) signaling through coupling with membrane surface receptor CD74, which in turn affected fibroblast functions and promoted MIF production. Our results reveal a novel function of trauma-induced MIF in the occurrence and development of joint capsule fibrosis. Further investigation of the underlying mechanism may provide potential therapeutic targets for PTJC.

Neferine promotes the apoptosis of HNSCC through the accumulation of p62/SQSTM1 caused by autophagic flux inhibition.

Head and neck squamous cell carcinoma (HNSCC), one of the most common malignancies worldwide, often has a poor prognosis due to the associated metastasis and chemoresistance. Hence, the development of more effective chemotherapeutics is critical. Neferine, a bisbenzylisoquinoline alkaloid isolated from the seed embryo of Nelumbo nucifera (common name: Lotus), exerts antitumor effects by regulating apoptosis and autophagy pathways, making it a potential therapeutic option for HNSCC. In our study, it was revealed that neferine inhibited the growth and induced the apoptosis of HNSCC cells both in vitro and in vivo. Furthermore, the results revealed that neferine activated the ASK1/JNK pathway by increasing reactive oxygen species production, resulting in the subsequent induction of apoptosis and the regulation of canonical autophagy in HNSCC cells. Moreover, a novel pro­apoptotic mechanism was described for neferine via the activation of caspase­8 following the accumulation of p62, which was caused by autophagic flux inhibition. These findings provided insights into the mechanisms responsible for the anticancer effect of neferine, specifically highlighting the crosstalk that occured between apoptosis and autophagy, which was mediated by p62 in HNSCC. Hence, the neferine­induced inhibition of autophagic flux may serve as the basis for a potential adjuvant therapy for HNSCC.

Radiation-Induced Soft Tissue Injuries in Patients With Advanced Mandibular Osteoradionecrosis: A Preliminary Evaluation and Management of Various Soft Tissue Problems Around Radiation-Induced Osteonecrosis Lesions.

OBJECTIVES: Radiation-induced soft-tissue injuries (STIs) in mandibular osteoradionecrosis (ORN) are not well studied regarding their correlations with nearby bone lesions. The aim of this study is to investigate the severity of radiation-induced STIs in advanced mandibular ORN and its relationship with hard-tissue damage and postoperative outcomes. METHODS: A retrospective study was performed in our institution from January 2017 to December 2019. Aside from demographic factors, the associations between the triad ORN variables (irradiation doses, ORN stages, ORN sizes) and radiation-related STI factors, vascular characteristics, and postoperative functional recovery were assessed. In addition, the severity of STI was also compared with treatment outcomes. Such correlations were established via both univariate and multivariable analyses. RESULTS: A total number of 47 patients were included. The median follow-up reached 27 months. Nasopharyngeal cancer was the histology type among most patients (n = 21, 44.7%). The median irradiation doses reached 62 Gy (range, 40-110 Gy). For STI, the symptom scoring equaled an average of 5.4 (range from 1 to 12), indicative of the severity of STI problems. During preoperative MRI examinations, signs of hypertrophy or edema (n = 41, 87.2%) were frequently discerned. Most patients (n = 23, 48.9%) also had extensive muscular fibrosis and infection, which required further debridement and scar release. Surprisingly, most STI factors, except cervical fibrosis (p = 0.02), were not in parallel with the ORN levels. Even the intraoperative soft-tissue defect changes could not be extrapolated by the extent of ORN damage (p = 0.096). Regarding the outcomes, a low recurrence rate (n = 3, 6.9%) was reported. In terms of soft tissue-related factors, we found a strong correlation (p = 0.004) between symptom scores and recurrence. In addition, when taking trismus into consideration, both improvements in mouth-opening distance (p < 0.001) and facial contour changes (p = 0.004) were adversely affected. Correlations were also observed between the intraoperative soft-tissue defect changes and complications (p = 0.024), indicative of the importance of STI evaluation and management. CONCLUSIONS: The coexistence of hard- and soft-tissue damage in radiation-induced advanced mandibular ORN patients reminds surgeons of the significance in assessing both aspects. It is necessary to take the same active measures to evaluate and repair both severe STIs and ORN bone lesions.