Osteoradionecrosis: a new concept of its pathophysiology

Temporal Bone Osteoradionecrosis: An 18-year, Single-Institution Experience

OBJECTIVES/HYPOTHESIS

To report the largest single-institution review of temporal bone osteoradionecrosis (TBORN), and characterize the disease's natural history, prognostic factors, management, and outcomes.

STUDY DESIGN

Retrospective chart review.

METHODS

Retrospective review was conducted to identify patients with TBORN. Pertinent data were extracted. Descriptive statistics were used to summarize patient, tumor, and treatment characteristics. Multivariable analyses were conducted to explore associations between these characteristics and time to TBORN diagnosis and risk of developing diffuse disease.

RESULTS

TBORN was identified in 145 temporal bones from 128 patients. Mean age at diagnosis was 62 years, and mean time to diagnosis after radiotherapy was 10 years. Age greater than 50 years was associated with earlier diagnosis. According to the Ramsden criteria, 76% of TBs had localized and 24% had diffuse disease at initial diagnosis; 37% had diffuse disease at last follow-up. On multivariable analysis, diabetes, three-dimensional conformal radiotherapy (3D-CRT), and periauricular skin malignancy were significant risk factors for developing diffuse disease. Localized disease was successfully managed with conservative measures, whereas surgery was often necessary for diffuse disease. When TBORN spread outside the mastoid or infratemporal fossa, conservative measures were always unsuccessful.

CONCLUSIONS

TBORN occurs earlier in older patients. While diffuse disease is less common than localized disease, it occurs more frequently in patients with diabetes, history of 3D-CRT, and periauricular skin malignancies. Conservative management is appropriate for localized disease, while surgery is often necessary for diffuse disease. The prognostic factors identified helped propose a TBORN staging system and treatment guidelines which may improve patient risk stratification and disease management.

LEVEL OF EVIDENCE

IV Laryngoscope, 2021.

Bacterial spectrum analysis and antimicrobial susceptibility study of osteoradionecrosis of the jaw in Southern China

OBJECTIVE

Osteoradionecrosis of the jaw (ORNJ) is one of the most common and serious complications after radiotherapy of head and neck malignancies due to the high incidence of nasopharyngeal cancer in Southern China. Clinicians lack understanding and consensus on anti-infective treatment in ORNJ lesions. This research aims to provide evidence for rational use of antibiotics by reviewing the bacterial spectrums and antimicrobial susceptibility test of ORNJ patients.

METHODS

We collected patient who was diagnosed with ORNJ from November 2012 to June 2019 in our hospital. Exudate or bone unexposed wound surface sampling, agar plates culturing, and susceptibility testing were analyzed. Descriptive statistics were used for data presentation.

RESULTS

A total of 219 samples were collected in our retrospective study. The most common cultured bacteria were Klebsiella pneumoniae (15.10%), Pseudomonas aeruginosa (13.54%), and Staphylococcus aureus (10.94%). Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 5.21% in the whole positive samples. Ticarcillin, Ofloxacin, Vancomycin, Tigecycline, and Meropenem were more susceptible than other antibiotics to treat uncontrollable infection.

CONCLUSIONS

Our research provided objective evidence for understanding the types of local bacterial flora and drug susceptibility in ORNJ lesions and gave a guiding reference for empirical antibiotics medication.

Predictors of osteoradionecrosis following irradiated tooth extraction

Background

Tooth extraction post radiotherapy is one of the most important risk factors of osteoradionecrosis of the jawbones. The objective of this study was to determine the predictors of osteoradionecrosis (ORN) which were associated with a dental extraction post radiotherapy.

Methods

A retrospective analysis of medical records and dental panoramic tomogram (DPT) of patients with a history of head and neck radiotherapy who underwent dental extraction between August 2005 to October 2019 was conducted.

Results

Seventy-three patients fulfilled the inclusion criteria. 16 (21.9%) had ORN post dental extraction and 389 teeth were extracted. 33 sockets (8.5%) developed ORN. Univariate analyses showed significant associations with ORN for the following factors: tooth type, tooth pathology, surgical procedure, primary closure, target volume, total dose, timing of extraction post radiotherapy, bony changes at extraction site and visibility of lower and upper cortical line of mandibular canal. Using multivariate analysis, the odds of developing an ORN from a surgical procedure was 6.50 (CI 1.37–30.91, p = 0.02). Dental extraction of more than 5 years after radiotherapy and invisible upper cortical line of mandibular canal on the DPT have the odds of 0.06 (CI 0.01–0.25, p < 0.001) and 9.47 (CI 1.61–55.88, p = 0.01), respectively.

Conclusion

Extraction more than 5 years after radiotherapy, surgical removal procedure and invisible upper cortical line of mandibular canal on the DPT were the predictors of ORN.

Surgical Management of Skull Base Osteoradionecrosis in the Cancer Population - Treatment Outcomes and Predictors of Recurrence: A Case Series

BACKGROUND

Skull base osteoradionecrosis (ORN) is a challenging treatment-related complication sometimes seen in patients with cancer. Although ORN management strategies for other anatomic sites have been reported, there is a paucity of data guiding the management of skull base ORN.

OBJECTIVE

To report a single-center tertiary care series of skull base ORN and to better understand the factors affecting ORN recurrence after surgical management.

METHODS

We conducted a retrospective cohort study of patients with skull base ORN treated at our center between 2003 and 2017. Univariate and multivariate binary logistic regressions were performed to identify predictors of recurrence.

RESULTS

A total of 31 patients were included in this study. The median age at ORN diagnosis was 61.1 yr (range, 32.8-84.9 yr). Of these 31 patients, 15 (48.4%) patients were initially treated medically. All 31 patients underwent surgery. Three (14.3%) of 21 patients treated with a free flap and 4 (50.0%) of 8 patients who underwent primary closure experienced recurrence. Cox regression analysis revealed that reconstruction with local tissue closure (P = .044) and ongoing treatment for active primary cancer (P = .022) were significant predictors of recurrence. The median overall survival from index surgery for ORN treatment was 83.9 mo. At 12-mo follow-up, 78.5% of patients were alive.

CONCLUSION

In this study, we assess the outcomes of our treatment approach, surgical debridement with vascularized reconstruction, on recurrence-free survival in patients with skull base ORN. Further studies with larger cohorts are needed to assess current treatment paradigms.

Osteoradionecrosis and microvascular free flap failure managed with negative pressure wound therapy: A case report

A 56-year-old female with a history of meningioma status post subtotal resection (Simpson grade IV) and extensive radiation therapy presented with osteoradionecrosis (O.R.N.) managed previously with a microvascular free flap (MVFF). The evaluation revealed worsening O.R.N. and a scalp defect of 15 × 10 cm. The patient underwent MVFF reconstruction utilizing a free latissimus muscle flap covered by meshed split-thickness skin graft (STSG). Her surgery was complicated by delayed free flap failure and Serratia marcescens growth, which occurred sometime after discharge from the hospital. This was managed with removal of the free muscle flap and skin graft, serial debridement's, antibiotics, and replacements of a synthetic dural matrix and negative pressure wound therapy (NPWT). Once a clean wound bed was again obtained, the patient underwent fasciocutaneous anterolateral thigh (A.L.T.) MVFF reconstruction, which was complicated by left hypoglossal nerve injury, dehiscence of the flap inset, and dehiscence of the neck access incision requiring revision surgery. On the last follow-up 2 weeks after her surgery, the patient had 100% flap viability and a 2 × 1.5 cm on the left parietal aspect of the flap healing be secondary intent. We demonstrate that NPWT is successful in managing open calvarial wounds due to O.R.N.

Noncultured Minimally Processed Adipose-Derived Stem Cells Improve Radiated Fracture Healing

Adipose-derived stem cells mitigate deleterious effects of radiation on bone and enhance radiated fracture healing by replacing damaged cells and stimulating angiogenesis. However, adipose-derived stem cell harvest and delivery techniques must be refined to comply with the US Food and Drug Administration restrictions on implantation of cultured cells into human subjects prior to clinical translation. The purpose of this study is to demonstrate the preservation of efficacy of adipose-derived stem cells to remediate the injurious effects of radiation on fracture healing utilizing a novel harvest and delivery technique that avoids the need for cell culture. Forty-four Lewis rats were divided into 4 groups: fracture control (Fx), radiated fracture control (XFx), radiated fracture treated with cultured adipose-derived stem cells (ASC), and radiated fracture treated with noncultured minimally processed adipose-derived stem cells (MP-ASC). Excluding the Fx group, all rats received a fractionated human-equivalent dose of radiation. All groups underwent mandibular osteotomy with external fixation. Following sacrifice on postoperative day 40, union rate, mineralization, and biomechanical strength were compared between groups at P < 0.05 significance. Compared with Fx controls, the XFx group demonstrated decreased union rate (100% vs 20%), bone volume fraction (P = 0.003), and ultimate load (P < 0.001). Compared with XFx controls, the MP-ASC group tripled the union rate (20% vs 60%) and demonstrated statistically significant increases in both bone volume fraction (P = 0.005) and ultimate load (P = 0.025). Compared with the MP-ASC group, the ASC group showed increased union rate (60% vs 100%) and no significant difference in bone volume fraction (P = 0.936) and ultimate load (P = 0.202). Noncultured minimally processed adipose-derived stem cells demonstrate the capacity to improve irradiated fracture healing without the need for cell proliferation in culture. Further refinement of the cell harvest and delivery techniques demonstrated in this report will enhance the ability of noncultured minimally processed adipose-derived stem cells to improve union rate and bone quality, thereby optimizing clinical translation.

Radiation therapy in head and neck cancer

This review summarizes the beginning of radiotherapy, techniques of modern radiation therapy with different types, toxicities induced by radiotherapy and their management. Head and neck radiation therapy is still improving for the better management and control of the cancer and induced radiotherapy toxicities.

Retrospective Analysis of a Modified Irrigation Method for Nasopharyngeal Carcinoma Patients With Post-Radiation Nasopharyngeal Necrosis

Purpose

Post-radiation nasopharyngeal necrosis (PRNN) is one of the most serious late effects of nasopharyngeal carcinoma (NPC) after radiotherapy. Standard conservative treatments are not always effective, and this study sought to investigate the feasibility of modified nasopharyngeal irrigation in the treatment of PRNN.

Methods

Between September 2011 and September 2018, 113 NPC patients with pathologically or radiologically diagnosed PRNN were analyzed retrospectively. All patients received the traditional conservative treatments of debridement of the necrotic tissues guided by an endoscope and systematic antibiotic therapy partly guided by culture results. The patients were divided into two groups according to the irrigation method used: traditional and modified groups. Modified irrigation used an irrigation device made by our hospital, guided by endoscopy, while the patients in the traditional irrigation group used a nasopharyngeal irrigation pot to wash the nasopharynx by themselves each day.

Results

Survival was affected by ICA (internal carotid artery) exposure, necrosis grade, and re-irradiation, but only ICA exposure and re-irradiation were found to be independent prognostic factors. The modified irrigation had a significantly more positive effect on the recovery rates of patients with mild- and moderate-grade PRNN than did traditional irrigation. The 2-year overall survival (OS) of the 113 patients was 68.4%. The modified irrigation was associated with better OS in the mild- and moderate-grade groups, in the one-course radiotherapy group, and in the low-risk group (according to the 2017 system).

Conclusions

More intense modified irrigation under the physicians control may be an effective treatment for PRNN, especially mild- and moderate-grade, one-course radiotherapy, or low-risk PRNN.

Various Therapeutic Methods for the Treatment of Medication-Related Osteonecrosis of the Jaw (MRONJ) and Their Limitations: A Narrative Review on New Molecular and Cellular Therapeutic Approaches

Medication-related osteonecrosis of the jaw (MRONJ) is one of the most interesting diseases in the field of maxillofacial surgery. In addition to bisphosphonates, the use of antiresorptive and antiangiogenic agents is known to be the leading cause. However, the exact pathogenesis of MRONJ has not been established, and various hypotheses have been proposed, such as oxidative stress-related theory. As a result, a definitive treatment protocol for MRONJ has not been identified, while various therapeutic approaches are applied to manage patients with MRONJ. Although the surgical approach to treat osteomyelitis of the jaw has been proven to be most effective, there are limitations, such as recurrence and delayed healing. Many studies and clinical trials are being conducted to develop another effective therapeutic modality. The use of some materials, including platelet concentrates and bone morphogenetic proteins, showed a positive effect on MRONJ. Among them, teriparatide is currently the most promising material, and it has shown encouraging results when applied to patients with MRONJ. Furthermore, cell therapy using mesenchymal stem cells showed promising results, and it can be the new therapeutic approach for the treatment of MRONJ. This review presents various treatment methods for MRONJ and their limitations while investigating newly developed and researched molecular and cellular therapeutic approaches along with a literature review.

The Particle Radiobiology of Multipotent Mesenchymal Stromal Cells: A Key to Mitigating Radiation-Induced Tissue Toxicities in Cancer Treatment and Beyond?

Mesenchymal stromal cells (MSCs) comprise a heterogeneous population of multipotent stromal cells that have gained attention for the treatment of irradiation-induced normal tissue toxicities due to their regenerative abilities. As the vast majority of studies focused on the effects of MSCs for photon irradiation-induced toxicities, little is known about the regenerative abilities of MSCs for particle irradiation-induced tissue damage or the effects of particle irradiation on the stem cell characteristics of MSCs themselves. MSC-based therapies may help treat particle irradiation-related tissue lesions in the context of cancer radiotherapy. As the number of clinical proton therapy centers is increasing, there is a need to decidedly investigate MSC-based treatments for particle irradiation-induced sequelae. Furthermore, therapies with MSCs or MSC-derived exosomes may also become a useful tool for manned space exploration or after radiation accidents and nuclear terrorism. However, such treatments require an in-depth knowledge about the effects of particle radiation on MSCs and the effects of MSCs on particle radiation-injured tissues. Here, the existing body of evidence regarding the particle radiobiology of MSCs as well as regarding MSC-based treatments for some typical particle irradiation-induced toxicities is presented and critically discussed.

Computed Tomography Radiomics Kinetics as Early Imaging Correlates of Osteoradionecrosis in Oropharyngeal Cancer Patients

Osteoradionecrosis (ORN) is a major side-effect of radiation therapy in oropharyngeal cancer (OPC) patients. In this study, we demonstrate that early prediction of ORN is possible by analyzing the temporal evolution of mandibular subvolumes receiving radiation. For our analysis, we use computed tomography (CT) scans from 21 OPC patients treated with Intensity Modulated Radiation Therapy (IMRT) with subsequent radiographically-proven ≥ grade II ORN, at three different time points: pre-IMRT, 2-months, and 6-months post-IMRT. For each patient, radiomic features were extracted from a mandibular subvolume that developed ORN and a control subvolume that received the same dose but did not develop ORN. We used a Multivariate Functional Principal Component Analysis (MFPCA) approach to characterize the temporal trajectories of these features. The proposed MFPCA model performs the best at classifying ORN vs. Control subvolumes with an area under curve (AUC) = 0.74 [95% confidence interval (C.I.): 0.61–0.90], significantly outperforming existing approaches such as a pre-IMRT features model or a delta model based on changes at intermediate time points, i.e., at 2- and 6-month follow-up. This suggests that temporal trajectories of radiomics features derived from sequential pre- and post-RT CT scans can provide markers that are correlates of RT-induced mandibular injury, and consequently aid in earlier management of ORN.

[Predictive factors for mandibular osteoradionecrosis after irradiation of head and neck cancers]

The identification of the different risk factors for mandibular osteoradionecrosis (ORN) must be done before and after the management of patients with head and neck cancer. Various clinical criteria for this severe radiation-induced complication are related to the patient (intrinsic radiosensitivity, malnutrition associated with thin weight loss, active smoking intoxication, microcapillary involvement, precarious oral status, hyposalivation) and/or related to the disease (oral cavity, large tumor size, tumor mandibular invasion). Therapeutic risk factors are also associated with a higher risk of ORN (primary tumor surgery, concomitant radio-chemotherapy, post-irradiation dental avulsion, preventive non-observance with the absence of stomatological follow-up and daily installation of gutters fluoride and, non-observance curative healing treatments). Finally, various dosimetric studies have specified the parameters in order to target the dose values distributed in the mandible, which increases the risk of ORN. An mean mandibular dose greater than 48-54Gy and high percentages of mandibular volume receiving 40 to 60Gy appear to be discriminating in the risk of developing an ORN.

Therapeutic alternatives in the management of osteoradionecrosis of the jaws. Systematic review

Background

to systematically review the literature, comparing the healing of osteoradionecrosis (ORN) among the therapeutic alternatives: surgical, pharmacological and combined.

Material and Methods

The review was organized according to the PRISMA protocol with regards to the following PICO question: patients with ORN of the jaws (P=Patient); all interventions reported (I = intervention); between all therapies (C=Comparison); healing of lesions (O=outcome).

Results

Surgical treatment was the most common choice (46.3%) followed by pharmacological treatment, exclusively (25.9%) or combined (26.9%). Treatment exclusively by surgical intervention seems to be most effective option, with 51.2% of the lesions healed, OR for healing of 5.7 (CI95% 1.9-16.9, p=0.002). Only 1 case (0.9%) corresponded to low level laser therapy.

Conclusions

It seems clear that early intervention with conservative surgical combined with pharmacological methods improves the prognosis of ORN.

Key words:Osteoradionecrosis, radiotherapy bone necrosis, hyperbaric oxygen, pentoxifylline, teriparatide, low level laser therapy.

A Novel Treatment Concept for Advanced Stage Mandibular Osteoradionecrosis Combining Isodose Curve Visualization and Nerve Preservation: A Prospective Pilot Study

Background

Osteoradionecrosis (ORN) of the mandible is a severe complication of radiation therapy in head and neck cancer patients. Treatment of advanced stage mandibular osteoradionecrosis may consist of segmental resection and osseous reconstruction, often sacrificing the inferior alveolar nerve (IAN). New computer-assisted surgery (CAS) techniques can be used for guided IAN preservation and 3D radiotherapy isodose curve visualization for patient specific mandibular resection margins. This study introduces a novel treatment concept combining these CAS techniques for treatment of advanced stage ORN.

Methods

Our advanced stage ORN treatment concept includes consecutively: 1) determination of the mandibular resection margins using a 3D 50 Gy isodose curve visualization, 2) segmental mandibular resection with preservation of the IAN with a two-step cutting guide, and 3) 3D planned mandibular reconstruction using a hand-bent patient specific reconstruction plate. Postoperative accuracy of the mandibular reconstruction was evaluated using a guideline. Objective and subjective IAN sensory function was tested for a period of 12 months postoperatively.

Results

Five patients with advanced stage ORN were treated with our ORN treatment concept using the fibula free flap. A total of seven IANs were salvaged in two men and three women. No complications occurred and all reconstructions healed properly. Neither non-union nor recurrence of ORN was observed. Sensory function of all IANs recovered after resection up to 100 percent, including the patients with a pathologic fracture due to ORN. The accuracy evaluation showed angle deviations limited to 3.78 degrees. Two deviations of 6.42° and 7.47° were found. After an average of 11,6 months all patients received dental implants to complete oral rehabilitation.

Conclusions

Our novel ORN treatment concept shows promising results for implementation of 3D radiotherapy isodose curve visualization and IAN preservation. Sensory function of all IANs recovered after segmental mandibular resection.

Is Adjunctive Hyperbaric Oxygen Treatment Alone or with Surgery the Proper Management for Active and Persistent Osteoradionecrosis?

ABSTRACT

This study enrolled patients with stage 3 osteoradionecrosis. There were three treatment modalities: antibiotics, hyperbaric oxygen therapy (HBOT), and surgery. Complete healing was the primary outcome. Multiple logistic regression analysis demonstrated that surgery with HBOT improved wound healing better than HBOT alone.

Osteomyocutaneous Free Fibula Flap Prevents Osteoradionecrosis and Osteomyelitis in Head and Neck Cancer Reconstruction

BACKGROUND

 Osteoradionecrosis (ORN) is one of the most severe complications of free fibula reconstruction after radiotherapy. The gold standard treatment of osteomyelitis involves extensive debridement, antibiotics, and sufficiently vascularized muscle flap coverage for better circulation. Therefore, we hypothesized that free fibula flap with muscle could decrease the risk of ORN.

METHODS

 This study consisted of 85 patients who underwent reconstruction with free fibula flap in head and neck cancer by a single reconstructive surgeon at Kaohsiung Veterans General Hospital over a period of 19 years (1998-2016). Patients with postoperative adjuvant radiotherapy were included in the study and were grouped by either free fibula osteocutaneous flap or free fibula osteomyocutaneous flap (with flexor hallucis longus muscle), and the incidence of ORN was compared.

RESULTS

 Of the 85 patients, 15 were reconstructed with osteocutaneous fibula flap and 70 were with osteomyocutaneous fibula flap. The rate of ORN or osteomyelitis was significantly lower in the muscle group (18.6%, n = 13/70 vs. 46.7%, n = 7/15, p = 0.020, Chi-square test).

CONCLUSION

 Vascularized muscle transfer increases perfusion of surrounding tissues and the bone flap, thereby decreasing the incidence of osteomyelitis or osteonecrosis.

Brachytherapy of the head and neck: An University of California Los Angeles guide to morbidity reduction

The head and neck (H&N) region is among the most intricate and functional part of our anatomy. Major functional nerves and blood vessels with importance that affect the entire body emanate from the base of skull. Brachytherapy plays an important role as a single modality therapy in early cancer of the lip and oral cavity and a supplemental role in the pharynx or in advanced or recurrent disease. Morbidity in the H&N is intensely personal and disabling. Its avoidance is critical in determining the success or failure of a treatment program, and it is essential to preservation of quality of life. This article summarizes the current literature regarding morbidity related to H&N brachytherapy to aid patients and physicians to achieve optimal outcomes.

Insights into the mechanism of vascular endothelial cells on bone biology

In the skeletal system, blood vessels not only function as a conduit system for transporting gases, nutrients, metabolic waste, or cells but also provide multifunctional signal molecules regulating bone development, regeneration, and remodeling. Endothelial cells (ECs) in bone tissues, unlike in other organ tissues, are in direct contact with the pericytes of blood vessels, resulting in a closer connection with peripheral connective tissues. Close-contact ECs contribute to osteogenesis and osteoclastogenesis by secreting various cytokines in the paracrine or juxtacrine pathways. An increasing number of studies have revealed that extracellular vesicles (EVs) derived from ECs can directly regulate maturation process of osteoblasts and osteoclasts. The different pathways focus on targets at different distances, forming the basis of the intimate spatial and temporal link between bone tissue and blood vessels. Here, we provide a systematic review to elaborate on the function of ECs in bone biology and its underlying mechanisms based on three aspects: paracrine, EVs, and juxtacrine. This review proposes the possibility of a therapeutic strategy targeting blood vessels, as an adjuvant treatment for bone disorders.

Osteoradionecrosis: Exposing the Evidence Not the Bone

Osteoradionecrosis is a relatively rare but potentially morbid and costly complication of radiation therapy for head and neck cancer. Multidisciplinary diagnosis and treatment are essential. Despite evidence guiding individual aspects of care for osteoradionecrosis, there is a lack of broad consensus on the overall diagnosis and management of this condition. This study comprehensively reviews the literature, with a focus on the past 10 years, to guide evaluation and treatment.

Tumor subsites and risk of osteoradionecrosis of the jaw in patients with oral cavity cancer: a national-based cohort study

PURPOSE

The association between the tumor subsites of the oral cavity and the risk of osteoradionecrosis of the jaw (ORNJ) remains unclear. We study the correlation between oral cavity tumor subsites and the risk of ORNJ in a nationwide population-based database.

METHODS

We enrolled 16,701 adult patients with oral cavity cancers who were treated with radiotherapy between 2000 and 2013. The subsites of the oral tumor, treatments of oral cavity cancers, and the timing of tooth extraction were examined for their association with ORNJ in oral cancer patients.

RESULTS

903 patients (5.40%) developed ORNJ. Of the relevant variables, pre-RT mandible surgery, tooth extraction either before or after RT, and tumor sites were associated with the risk of ORNJ. The adjusted HRs for ORNJ in the mouth floor, gums, retromolar, and buccal cancer were 2.056 (1.490-2.837), 1.909 (1.552-2.349), 1.683 (1.105-2.562), and 1.303 (1.111-1.528), respectively, compared with the risk of tongue cancer. There was no significant difference in the risk of ORNJ between the pre-RT extraction group, the during-RT extraction group, and the post-RT extraction (less than 6 months) group; the post-RT extraction (more than 6 months) group had a significantly higher risk of ORNJ.

CONCLUSIONS

This study demonstrated that oral cavity tumor subsite is an independent risk factor of ORNJ after RT. Post-RT extraction (less than 6 months) group did not carry a significantly higher risk of ORNJ compared with pre-RT extraction group or during RT extraction group.

Four Lessons Learned from Complications in Head and Neck Microvascular Reconstructions and Prevention Strategies

Free flap reconstruction in the head and neck region is a complex field in which patient comorbidities, radiation therapy, tumor recurrence, and variability of clinical scenarios make some cases particularly challenging and prone to devastating complications. Despite low free flap failure rates, the impact of flap failure has enormous consequences for the patients.

METHODS

Acknowledging and predicting high risk intra- and postoperative situations and having planned strategies on how to deal with them can decrease their rate and improve the patient's reconstructive journey.

RESULTS

Herein, the authors present 4 examples of significant complications in complex microvascular head and neck cancer reconstruction, encountered for the last 10 years: compression and kinking of the vascular pedicle, lack of planning of external skin coverage in osteoradionecrosis, management of the vessel-depleted neck, and vascular donor site morbidity after fibula harvest.

CONCLUSION

The authors reflect on the causes and propose preventative strategies in each peri-operative stage.

The use of pentoxifylline, tocopherol and clodronate in the management of osteoradionecrosis of the jaws

AIMS

Medical management of osteoradionecrosis (ORN) via pentoxifylline, tocopherol (PENTO) and clodronate (PENTOCLO) has shown both promise and early positive outcomes. We aimed to determine clinical outcomes for patients with established ORN managed solely via PENTO or PENTOCLO.

METHODS

The study retrospectively reviewed and collected data from the medical records of 169 patients diagnosed with ORN and treated via medical management. Patients that received any additional interventions such as surgery or hyperbaric oxygen were not included.

RESULTS

Medical management led to healed ORN in 54.4% (n = 92/169) of patients after an average of 12.9 months. Outcome comparison between PENTO and PENTOCLO identified the former regime to be significantly superior (p = 0.0001). There is an inverse relationship with increasing ORN severity and healing with medical management (p < 0.0001) with oropharyngeal cancer (p = 0.0347) patients responding favourably via this approach. Infection had a critical role in the final outcome with those healing requiring 1.3 antibiotic prescriptions, while those that had disease progression requiring 4.3 prescriptions.

CONCLUSION

Medical management is a viable treatment option for ORN. It appears to be most effective in Notani I and non-infected ORN. When healing was not achieved the regime was able to stabilise the condition.

ODONTOLOGICAL EFFECTS OF IONIZING RADIATION (review)

BACKGROUND

Odontological effects of ionizing radiation (IR) as a result of radiotherapy, the consequences of accidents at nuclear power plants and industry, individual occupational exposure, etc. deserve significant attention interns of radiation medicine and radiation safety.

OBJECTIVE

to analyze and summarize clinical and experimental data on the odontological radiation effects.

MATERIALS AND METHODS

OBJECT

the pathological changes in the hard tissues of teeth, pulp, periodontium, mucousmembranes of the mouth and jaws due to exposure to IR.

METHOD

search in the PubMed / MEDLINE, Google Scholarabstract medical and biological databases, scientific libraries of the relevant sources of scientific information.

RESULTS

Radiobiological effects of IR due to its direct and indirect action are manifested throughout the period ofodontogenesis and formation of the facial skeleton. Experimental and clinical data (in children and adults) indicatethe increased risk of dental caries, reduction of pain threshold and vascularization of tooth pulp along with its fibrosis and atrophy, periodontal dysfunction, which predispose to a high probability of tooth loss. Abnormalities in theactivity of osteoblasts and cementoblasts of dental periosteum and osteoblasts of alveolar process in combinationwith circulatory disorders due to endothelial cell death, hyalinization, thrombosis and vascular obliteration increasethe risk of jaw osteoradionecrosis. Children who have undergone a prenatal exposure to IR as a result of theChornobyl NPP accident have a premature change of teeth. Deterioration of periodontal tissues and early development of acute and complicated dental caries are typical for children and adults affected by the Chornobyl disaster.

CONCLUSIONS

Summarized data on the effects of radiation exposure under different conditions on teeth primordia(i.e. immature teeth), their formation and eruption in experimental and clinical settings, as well as on the odontological radiation effects in adults are summarized. Condition of the teeth in the Chornobyl NPP accident survivorsis described. Understanding and taking into account the radiobiological odontological effects is necessary in thelight of planning, preparing, and conducting local radiation therapy and developing the standards of radiation safety and measures to protect professionals and the public in the event of possible radiation accidents at the nuclearpower plants and industry facilities.

Osteoradionecrosis of the Midface and Mandible: Pathogenesis and Management

Radiation therapy is an important and commonly used treatment modality for head and neck cancers. Osteoradionecrosis (ORN) is a potential debilitating complication of treatment, which most commonly affects the mandible. Management strategies are tailored to the severity of disease. Medical management including oral rinses, irrigations, antibiotics, and pharmacological treatments is viable for mild-to-moderate ORN. More severe disease is best addressed with a combination of medical management and surgical intervention aimed at aggressively removing devitalized tissue until bleeding bone is encountered and reconstructing the soft tissue and bone defect. Reconstruction with either regional vascularized flaps or vascularized osteocutaneous free flaps in case of larger full-thickness bone defects (greater than 6 cm) or anterior mandible (medial to mental foramen) is most appropriate. Maxillary ORN complications can present with a wide range of functional problems and facial disfigurement. Life-threatening and time-sensitive problems should be treated first, such as skull base bone coverage or correction of severe ectropion, to avoid blindness from exposure keratopathy. Then, less time-sensitive issues can be addressed next, such as nasal obstruction, velopharyngeal insufficiency, and chronic tearing. It may require a combination of specialists from different disciplines to address various issues that can arise from maxillary ORN.

The Role of Hyperbaric Oxygen in Head and Neck Reconstruction and Facial Cosmetic Surgery

Hyperbaric oxygen (HBO) is a treatment modality with the primary mechanism of therapy being the delivery of oxygen to hypoxic tissues. A review of HBO applications in the field of head and neck reconstruction and facial cosmetic surgery is provided. HBO can be useful in the management of radiation sequelae and treatment of compromised flaps and grafts. It may also have application in tissue compromise following cosmetic surgery and dermal fillers. We provide evidence from the available literature as well as highlight our experience in using HBO in head and neck reconstruction.

Radiation Necrosis of the Lateral Skull Base and Temporal Bone

Radiation therapy plays a critical role in the treatment of malignancies involving the head and neck. Although the therapeutic effects of ionizing radiation are achieved, normal tissues are also susceptible to injury and significant long-term sequelae. Osteoradionecrosis of the temporal bone (ORNTB) is among the many complications that can arise after therapy. ORNTB is a debilitating and potentially lethal condition that continues to challenge patients and treating physicians. Herein, we review the pathophysiology, presentation, work-up, and management of ORNTB.

Medication-related osteonecrosis and osteoradionecrosis of the jaws: Update and current management

Medication related osteonecrosis of the jaws (MRONJ) and osteoradionecrosis of the jaws (ORNJ) are two different diseases of quite similar appearance. MRONJ is mainly due to antiresorptive or antiangiogenic drug therapy and ORNJ to radiotherapy. The present work aimed at presenting and comparing the current knowledge on MRONJ and ORNJ. They both present as an exposure of necrotic bone and differ in some clinical or radiological characteristics, clinical course and mostly in treatment. They share similar risk factors. A tooth extraction is more frequently found as a triggering factor in MRONJ. The frequency of a maxillary localisation seems higher for MRONJ. On computed tomographic images, a periosteal reaction seems characteristic of MRONJ. More frequent pathological fractures seem to occur in ORNJ. It is mandatory, for ORNJ diagnosis, to exclude a residual or recurrent tumour using histological examination. Both MRONJ and ORNJ are challenging to treat and cannot be managed similarly. For both, it would still be worth to optimise awareness within the medical community, patients' oral hygiene and dental cares to improve their prevention and make their incidences decrease. Conservative therapy is more frequently achieved for MRONJ than ORNJ and surgical resection is more often performed for ORNJ. For both diseases, the last treatment possible in refractory cases is a surgical extensive resection with free flap reconstruction. A MRONJ classification is widely used today, whereas no consensus exists to date for ORNJ classification. We propose a classification that could play this role.

Oral management strategies for radiotherapy of head and neck cancer

Radiotherapy, often with concomitant chemotherapy, has a significant role in the management of head and neck cancer, however, radiotherapy induces adverse events include oral mucositis, hyposalivation, loss of taste, dental caries, osteoradionecrosis, and trismus, all of which have an impact on patients' quality of life. Therefore, it is necessary to implement oral management strategies prior to the initiation of radiotherapy in patients with head and neck cancer. Since 2014, the National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology (NCCN Guidelines) have enumerated the "Principles of Dental Evaluation and Management (DENT-A)" in the section on head and neck cancers, however, oral management was not explained in detail. Oral management has not been achieved a consensus protocol. The aim of this literature is to show that oral management strategy include removal infected teeth before the start of radiotherapy to prevent osteoradionecrosis, oral care for preventing severe oral mucositis to support patient complete radiotherapy during radiotherapy, and prevent of dental caries followed by osteoradionecrosis after radiotherapy.

Integrating Finite Element Death Technique and Bone Remodeling Theory to Predict Screw Loosening Affected by Radiation Treatment after Mandibular Reconstruction Surgery

This study developed a numerical simulation to understand bone mechanical behavior and micro-crack propagation around a fixation screw with severe mandibular defects. A mandible finite element (FE) model was constructed in a rabbit with a right unilateral body defect. The reconstruction implant was designed to be fixed using six screws distributed on the distal and mesial sides. The element death technique provided in FE analysis was combined with bone remodeling theory to simulate bone necrosis around the fixation screw in which the strain value reached the overload threshold. A total of 20 iterations were performed to observe the micro-crack propagation pattern for each screw according to the high strain locations occurring in each result from consecutive iterations. A parallel in vivo animal study was performed to validate the FE simulation by placing specific metal 3D printing reconstruction implants in rabbits to compare the differences in bone remodeling caused by radiation treatment after surgery. The results showed that strain values of the surrounding distal bone fixation screws were much larger than those at the mesial side. With the increase in the number of iteration analyses, the micro-crack prorogation trend for the distal fixation screws can be represented by the number and element death locations during the iteration analysis process. The corresponding micro-movement began to increase gradually and induced screw loosening after iteration calculation. The strained bone results showed that relatively high bone loss (damage) existed around the distal fixation screws under radiation treatment. This study concluded that the FE simulation developed in this study can provide a better predictive diagnosis method for understanding fixation screw loosening and advanced implant development before surgery.

Hyperbaric oxygen for radiation-induced cystitis: A long-term follow-up

INTRODUCTION AND OBJECTIVES

Bladder complications may be seen in up to 12% of patients treated with pelvic irradiation. Hyperbaric oxygen therapy (HBOT) is an option for the management of radiation-induced hemorrhagic cystitis (RIHC). The aim of this study was to evaluate the efficacy of HBOT in radiation cystitis and to identify the predictive factors for a successful outcome.

MATERIAL AND METHODS

We retrospectively reviewed 105 patients diagnosed with RIHC which were treated with HBOT between 2007 and 2016 in our institution. Patients received 100% oxygen in a multiplace hyperbaric chamber at 2.4atm for 80minutes. All patients fulfilled a questionnaire documenting symptom severity pre-HBOT and at the end of the follow-up period.

RESULTS

After a median of 40 HBOT sessions, there was success rate of 92,4% in the control of hematuria. During our follow-up period (median of 63 months) 24,7% patients presented with recurrence of hematuria. The mean score of the questionnaire-assessed variables: dysuria, urinary frequency and hematuria, was significantly lower after the follow-up period (P<.05). Our data shows that the sooner HBOT is delivered after the first episode of hematuria, better response rates are achieved and lower recurrences concerning hematuria were registered (P<.05). No serious complications were observed.

CONCLUSIONS

Our results support the safety and long-term benefits of HBOT on RIHC and other distressful bladder symptoms, which represents an expected improvement of quality of life in our patients.

Complications of Dentoalveolar Surgery

This article explores how to prevent and manage complications of dentoalveolar surgery. Many complications are avoidable. Surgical skills and knowledge of anatomy play an important role in prevention of complications. Prevention starts with detailed history and physical examination of the patient. Key to perioperative management of patients is risk assessment. Without a proper history and physical examination, the clinician is unable to assess the risk of performing surgery and anesthesia for each patient. Some illnesses and medications increase the risk of complications. The following complications are discussed: alveolar osteitis, displacement, fracture, hemorrhage, infection, nonhealing wound, oroantral communication, swelling, and trismus.

Exosome secreted by human gingival fibroblasts in radiation therapy inhibits osteogenic differentiation of bone mesenchymal stem cells by transferring miR-23a

Radiation-induced fibrosis is recently established as a main reason for osteoradionecrosis of the jaw (ORNJ), anti-eradiation fibrosis drugs achieve satisfactory therapeutic effects. However, the molecular mechanism remain to be fully elucidated. In this study, we found the inhibitory effect of irradiation activated gingival fibroblasts on osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs). Moreover, irradiation-activated-fibroblasts significantly increased miR‑23a expression in hBMSCs. Decreased miR‑23a enhanced osteogenic differentiation of BMSCs, and elevated miR‑23a inhibited this process via directly targeting CXCL12. Finally, exosome released from irradiation-activated-fibroblasts inhibited osteogenic differentiation of BMSCs, and these exosome mediated delivery of miR-23a and further regulated miR-23a/CXCL12 axis in hBMSCs. Therefore, our findings suggest that by transferring miR-23a, exosome secreted by human gingival fibroblasts in radiation therapy serves a vital role in osteogenic differentiation of hBMSCs, which may provide novel clinical treatments for ORNJ.

Use of dentures, receipt of information, quality of life, and oral function following radiotherapy for head and neck cancer

BACKGROUND

Teeth with a poor prognosis are often extracted prior to radiotherapy for head and neck cancer (HNC) in order to help prevent the need for dental treatment after radiotherapy that might in turn lead to the development of osteoradionecrosis. However, the details and impact of replacing missing teeth after radiotherapy for HNC have received little attention, especially from the patients' perspective.

AIMS

This study aimed to assess the use, satisfaction, and impact of denture use following radiotherapy for HNC. The study also sought to determine patients' satisfaction with information about replacing their missing teeth postradiotherapy. Finally, this study also aimed to assess interest in replacing missing teeth for those who had not done so.

METHODS

A structured, validated, and reliable questionnaire was sent to HNC patients who had received radiotherapy and had missing teeth at the time of discharge. In addition to demographic details and self-reported oral hygiene, the questionnaire included questions on use of (or interest in) dentures, satisfaction with dentures, satisfaction with information about replacing missing teeth, QoL as measured by two questions from the short version of WHOQoL-BREF, and oral functioning as measured by BCSQ-H&N. Demographic details and clinical details were extracted from the hospital records.

RESULTS

N = 80 (24%) returned a completed questionnaire. Participants had an average of 12 missing teeth (SD = 8.05). Most (n = 60, 75%) had not replaced their missing teeth. Of these, 35 (58%) were very or extremely interested in doing so. For HNC survivors who wore dentures, there was variable satisfaction and a number of side-effects of wearing dentures. Satisfaction with information about replacing missing teeth was low. There was no statistical difference in QoL or oral functioning between participants who wore dentures and participants who did not wear dentures. However, those with dentures reported fewer problems with carrying out daily routines as measured by the oral functioning tool.

CONCLUSIONS

QoL and oral functioning were similar regardless of denture use, highlighting reduced oral function in both those with and without dentures. In those who had not replaced their missing teeth, there was substantial interest in doing so and thus may be an unmet need. The dental team could offer HNC survivors more support after radiotherapy and following denture provision to improve information about denture use and increase satisfaction with dentures.

Development of a standardized mucositis and osteoradionecrosis animal model using external radiation

Objectives

Although the side effects of radiation therapy vary from mucositis to osteomyelitis depending on the dose of radiation therapy, to date, an experimental animal model has not yet been proposed. The aim of this study was to develop an animal model for assessing complications of irradiated bone, especially to quantify the dose of radiation needed to develop a rat model.

Materials and Methods

Sixteen Sprague-Dawley rats aged seven weeks with a mean weight of 267.59 g were used. Atraumatic extraction of a right mandibular first molar was performed. At one week after the extraction, the rats were randomized into four groups and received a single dose of external radiation administered to the right lower jaw at a level of 14, 16, 18, or 20 Gy, respectively. Clinical alopecia with body weight changes were compared and bony volumetric analysis with micro-computed tomography (CT), histologic analysis with H&E were performed.

Results

The progression of the skin alopecia was different depending on the irradiation dose. Micro-CT parameters including bone volume, bone volume/tissue volume, bone mineral density, and trabecular spaces, showed no significant differences. The progression of osteoradionecrosis (ORN) along with that of inflammation, fibrosis, and bone resorption, was found with increased osteoclast or fibrosis in the radiated group. As the radiation dose increases, osteoclast numbers begin to decrease and osteoclast tends to increase. Osteoclasts respond more sensitively to the radiation dose, and osteoblasts are degraded at doses above 18 Gy.

Conclusion

A standardized animal model clinically comparable to ORN of the jaw is a valuable tool that can be used to examine the pathophysiology of the disease and trial any potential treatment modalities. We present a methodology for the use of an experimental rat model that incorporates a guideline regarding radiation dose.

Regeneration of mandibular osteoradionecrosis with autologous cross-linked serum albumin scaffold

Osteoradionecrosis is one of the most severe complications of radiotherapy administered for head and neck tumors. We present the first two cases of advanced and refractory mandibular osteoradionecrosis treated by application of a novel autologous cross-linked 3D serum matrix. Patients were followed clinically and radiographically up to 24 months. Complete wound healing and intact mucosal cover were achieved in both cases. At 12 months, the radiographic values showed an almost complete regeneration of the bone defect, which continued a favourable progression increased to the maximum by 24 months after surgery. The use of an autologous serum-derived scaffold proved to be a quick, predictable, cost-effective and safe adjunct to the conservative surgical treatment of this pathology.

Neck stiffness after transoral pharyngolaryngeal surgery for squamous cell carcinoma

INTRODUCTION

Pyogenic spondylodiscitis is a rare, destructive intervertebral disc infection.

CASE SUMMARY

We describe a case of C2-C3 pyogenic spondylodiscitis after transoral surgery of the posterior pharyngeal wall in a 64-year-old man with a history of oropharyngeal squamous cell carcinoma (SCC) treated by neck irradiation (45Gy). Ten years after initial treatment, he underwent total laryngectomy for laryngeal SCC, together with transoral resection of carcinoma in situ (CIS) of the posterior pharyngeal wall followed by BioDesign® tissue repair graft. Five months later, C2-C3 spondylodiscitis was diagnosed with the formation of a fistula between the posterior pharyngeal wall and the intervertebral disc. Antibiotic therapy was administered for a total duration of 3 months (multi-susceptible Escherichia coli). Eight months after the diagnosis of spondylodiscitis, the patient died from carotid artery rupture following another course of radiotherapy for lymph node recurrence.

DISCUSSION

Larger-scale studies are necessary to evaluate the prevalence and risk factors of radiation-induced spondylodiscitis that currently remain poorly elucidated. The best treatment strategy (choice and duration of antibiotic therapy) and the optimal frequency of follow-up must be determined and the value of preventive measures (biomaterial, flap repair) needs to be evaluated.

Development of a Rat Model of Mandibular Irradiation Sequelae for Preclinical Studies of Bone Repair

Repairing mandibular bone defects after radiotherapy of the upper aerodigestive tract is clinically challenging. Although bone tissue engineering has recently generated a number of innovative treatment approaches for osteoradionecrosis (ORN), these modalities must be evaluated preclinically in a relevant, reproducible, animal model. The objective of this study was to evaluate a novel rat model of mandibular irradiation sequelae, with a focus on the adverse effects of radiotherapy on bone structure, intraosseous vascularization, and bone regeneration. Rats were irradiated with a single 80 Gy dose to the jaws. Three weeks after irradiation, mandibular bone defects of different sizes (0, 1, 3, or 5 mm) were produced in each hemimandible. Five weeks after the surgical procedure, the animals were euthanized. Explanted mandibular samples were qualitatively and quantitatively assessed for bone formation, bone structure, and intraosseous vascular volume by using micro-computed tomography, scanning electron microscopy, and histology. Twenty irradiated hemimandibles and 20 nonirradiated hemimandibles were included in the study. The bone and vessel volumes were significantly lower in the irradiated group. The extent of bone remodeling was inversely related to the defect size. In the irradiated group, scanning electron microscopy revealed a large number of polycyclic gaps consistent with periosteocytic lysis (described as being pathognomonic for ORN). This feature was correlated with elevated osteoclastic activity in a histological assessment. In the irradiated areas, the critical-sized defect was 3 mm. Hence, our rat model of mandibular irradiation sequelae showed hypovascularization and osteopenia. Impact statement Repairing mandibular bone defects after radiotherapy of the upper aerodigestive tract is clinically challenging. Novel tissue engineering approaches for healing irradiated bone must first be assessed in animal models. The current rat model of mandibular irradiation sequelae is based on tooth extraction after radiotherapy. However, the mucosal sequelae of radiotherapy often prevent the retention of tissue-engineered biomaterials within the bone defect. We used a submandibular approach to create a new rat model of mandibular irradiation sequelae, which enables the stable retention of biomaterials within the bone defect and should thus facilitate the assessment of bone regeneration.

Quantitative Dynamic Contrast-Enhanced MRI Identifies Radiation-Induced Vascular Damage in Patients With Advanced Osteoradionecrosis: Results of a Prospective Study

PURPOSE

We aim to characterize the quantitative dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters associated with advanced mandibular osteoradionecrosis (ORN) compared with the contralateral normal mandible.

METHODS AND MATERIALS

Patients with a diagnosis of advanced ORN after curative-intent radiation treatment of head and neck cancer were prospectively enrolled after institutional review board approval and study-specific informed consent were obtained. Quantitative maps generated with the Tofts and extended Tofts pharmacokinetic models were used for analysis. Manual segmentation of advanced ORN 3-dimensional volume was done using anatomic sequences to create ORN volumes of interest (VOIs). Subsequently, normal mandibular VOIs were segmented on the contralateral healthy mandible of similar volume and anatomic location to create control VOIs. Finally, anatomic sequences were coregistered to DCE sequences, and contours were propagated to the respective parameter maps.

RESULTS

Thirty patients were included. The median time to ORN diagnosis after completion of IMRT was 38 months (range, 6-184 months), whereas median time to ORN progression to advanced grade after initial diagnosis was 5.6 months (range, 0-128 months). There were statistically significant higher K^trans and V_e in ORN-VOIs compared with controls (0.23 vs 0.07 min^-1, and 0.34 vs 0.15; P < .0001 for both). The average relative increase of K^trans in ORN-VOIs was 3.2-fold higher than healthy mandibular control VOIs. Moreover, the corresponding rise of V_e in ORN-VOIs was 2.7-fold higher than in the controls. Using combined K^trans and V_e parameters, 27 patients (90%) had at least a 200% increase of either of the studied parameters in the ORN-VOIs compared with their healthy mandible VOIs.

CONCLUSIONS

Our results confirm that there is a quantitatively significant higher degree of leakiness in the mandibular vasculature as measured using DCE-MRI parameters of areas with advanced ORN versus healthy mandible.

Fascio-cutaneous-free flaps as primary reconstruction in salvage total laryngectomy

INTRODUCTION

Salvage total laryngectomy (STL) is the most common treatment for recurrent laryngeal cancer after (chemo)-radiotherapy [(C)RT]. In this scenario, a higher rate of local wound complications, such as pharyngo-cutaneous fistula (PCF) and pharyngo-esophageal stenosis (PES), is generally expected. The aim of the present study is to evaluate outcomes using a standardized reconstructive protocol.

METHODS

Between 2009 and 2019, patients undergoing STL after (C)RT were collected at two referral hospitals with the objective of evaluating surgical outcomes using a standardized reconstructive policy based on the use of fascio-cutaneous free flaps as inlay patch grafts and a long-lasting salivary bypass stent.

RESULTS

Fifty-five patients (mean age, 66 years; male-to-female ratio, 8:1) were included in the study. Previous treatments were RT in 22 (40%) patients, CRT in 21 (38.2%), and partial laryngeal surgery followed by adjuvant (C)RT in 12 (21.8%). Reconstruction was accomplished by radial forearm and anterolateral thigh free flaps in 16 (29.1%) and 39 (70.9%) patients, respectively. Flap success rate was 98.2%. Concerning postoperative complications, we encountered 3 PCFs (5.4%) and 1 PES (1.8%).

CONCLUSION

The standardized reconstructive protocol analyzed herein granted significantly lower rates of PCF and PES after STL compared with data available in the literature.

External fixation greatly improves outcomes in the surgical treatment of osteoradionecrosis of the jaws without affecting quality of life: a five-year retrospective study

Osteoradionecrosis of the jaw can be treated using both conservative treatment and surgery. External fixation may be used to bridge large resection defects after sequestrectomy for stabilisation and before secondary mandibular reconstruction. We designed a retrospective analysis of 70 patients with osteoradionecrosis treated between the years 2014 and 2018, and found that the use of external fixation greatly improves their outcomes. Patients were grouped according to Notani's classification: those who had Notani I disease were treated surgically but without external fixation; and those with Notani II and Notani III disease were eligible for external fixation. In those with Notani II disease, there was a significant reduction in the number of pathological fractures that occurred with external fixation. In those with Notani III disease, the success rate of primary sequestrectomy was only 1:14; however, those treated with external fixation all successfully healed after their first operation. It was hypothesised that although external fixation would improve outcome, it would come at a detriment to their quality of life (QoL). However, in a subset of these patients, we showed that in addition to increasing successful healing, patients' QoL with the external fixator was no worse than when they had an active osteonecrotic lesion. The treatment of osteoradionecrosis is cumbersome and advanced stages are associated with more complications. The use of an external fixator significantly reduces the probability of pathological fractures and increases the rate of successful healing in patients after mandibular resection. It does this without greatly interfering with patients' lives, while improving their condition sufficiently to allow for subsequent mandibular reconstruction.

A Retrospective Cohort and Systematic Review of Non-Operative Management of Exposed Calvaria Post-Radiotherapy

Scalp defects with exposed calvaria that have previously been irradiated present a unique reconstructive challenge. Patients with previously radiated scalp defects often have few reconstructive options due to poor health or personal choice. The aim of this study was to evaluate the results of non-operative management for patients with prior radiotherapy to the scalp who developed exposed calvaria. The outcomes of interest were major and minor complications related to exposed calvaria with a time frame of follow-up of greater than one year or death from any cause. A retrospective chart review was performed to identify patients with prior radiotherapy and surgery for skin cancer to the scalp who subsequently developed exposed calvaria. Data from four surgeons from 2008 to 2019 was collected. Next, a systematic review of PubMed, EMBASE, Cochrane Library, and CINAHL was conducted to identify articles in which non-operative management was utilized for exposed calvaria post-radiotherapy. Nineteen patients were identified who received radiotherapy either before developing recurrent malignancy requiring operation or requiring radiation postoperatively because of close or involved margins and who subsequently developed exposed calvaria. Six of these patients had an additional attempt at local flap or skin grafting that failed. All patients had an American Society of Anesthesiologists score of three or four. All were managed with local wound care. Ten patients had near-complete healing with wound care alone. Eight patients are still alive from one to six years after the presentation. One patient, who remains alive, developed an intracranial abscess requiring long-term antibiotics but was medically compromised by concomitant myelodysplastic syndrome, mantle cell lymphoma on chemotherapy, atrial fibrillation on anticoagulation, and heart failure. Three patients developed new malignancies requiring re-operation with watchful waiting. Two of the three cases resulted in failure to control disease, but control of malignancy occurred in one case with resection of recurrent cancer and exposed bone.  The systematic review of the literature yielded three studies that met the inclusion criteria. None of the studies encountered cases of meningitis, encephalitis, or death due to the non-operative treatment of exposed calvaria post radiation. Coverage of the calvaria with well-vascularized tissue is the reconstructive goal in the majority of circumstances. This case series and systematic review found that non-operative management of exposed calvaria post-radiotherapy can be an option for patients who are either not candidates for aggressive surgical treatment or who refuse surgery.

Denture use and dental risk factors associated developing osteoradionecrosis after head and neck radiotherapy: A retrospective analysis of hospital records

OBJECTIVES

This study aimed to assess the association between denture use and occurrence of osteoradionecrosis (ORN) following radiotherapy for head and neck cancer (HNC).

MATERIALS AND METHODS

Medical records of 439 HNC patients treated with radiotherapy at Guy's & St Thomas' NHS Foundation Trust (London, UK) (2014-2019) who had missing teeth at the time of discharge were reviewed. Descriptive statistics were used to summarise the participant characteristics and outcome measures. Logistic regression analysis was used to identify factors associated with occurrence of ORN.

RESULTS

Patients had an average of 14 missing teeth and 39 % wore dentures. Twenty-two (5 %) developed ORN. Out of 22 who developed ORN, 11 (50 %) wore dentures. Of these, 5 patients developed ORN in areas contacted by dentures. Denture use was not significantly associated with the occurrence of ORN (OR = 1.94; 95%CI = 0.79-4.81; p-value = 0.150). Longer duration of radiotherapy (OR =1.03; 95%CI = 1.00-1.06; p-value= 0.048) and more missing teeth in the lower anterior area (OR = 1.11; 95%CI = 1.01-1.22; p-value = 0.024) were significantly associated with the development of ORN.

CONCLUSIONS

Within the limitations of this single-centre study in which few patients developed ORN, denture use may not be a risk factor for ORN following radiotherapy for HNC. This is likely to be the case if dentures are well-fitting and not causing sores or irritation.

CLINICAL SIGNIFICANCE

Replacement of the missing teeth with dentures in HNC patients post-radiotherapy may be a suitable choice for many HNC survivors. However, a powered study in a large cohort that includes clinical evaluation of dentures and the quality of fit alongside denture wearing experience would be useful to further assess the impact of denture use on the development of ORN.

Tooth extraction before radiotherapy is a risk factor for developing osteoradionecrosis of the jaws: A systematic review

OBJECTIVES

The aim of this systematic review was to estimate the osteoradionecrosis rate in patients with head and neck cancer due to teeth extraction performed before radiotherapy and to identify possible risk factors.

MATERIAL AND METHODS

PRISMA protocol was used to evaluate and present the results. PubMed, Scopus and Web of Science were used as search engines: English full-length papers of clinical studies, in peer-reviewed journals, were investigated. Cumulative meta-analysis was performed with a random effects model (PROSPERO registration code: CRD42018079986).

RESULTS

Among 2,020 records screened, 8 were included in this review. Sixteen of 494 patients who underwent tooth extraction before radiotherapy developed osteoradionecrosis, with an osteoradionecrosis incidence of 2.2% (95% Confidence of Interval = 0.6-3.9, p < .185, I²  = 3,044%). All cases were reported in the mandible. No other clinical risk factor for osteoradionecrosis was detected.

CONCLUSIONS

Even if it is generally recommended to remove oral foci before radiotherapy, this systematic review confirmed that teeth extractions before radiotherapy represent a risk factor for osteoradionecrosis; the considerable amount of missing data prevented us from identifying other possible risk factors for osteoradionecrosis onset. Major efforts should be done to perform sounder methodological clinical investigations.

Dental prevention of maxillo-mandibular osteoradionecrosis: A ten-year retrospective study

INTRODUCTION

Osteoradionecrosis (ORN) remains a frequent complication of radiotherapy in head and neck cancer. As ORN management is often complex, it is essential to focus on its prevention, mainly by dental prophylaxis. The objectives of this study were to evaluate a dental preventive approach based on ORN data and to highlight individual risk factors statistically associated with time-to-ORN.

MATERIALS AND METHODS

A retrospective study (January 2004-December 2013) included 415 patients with head and neck cancer who received radiotherapy in their treatment with at least 50 Grays on maxillo-mandibular bones. Pre-radiotherapy dental assessment (clinical and radiological) and prevention (with standardised extraction protocol) were performed.

RESULTS

The ORN rate was 7.5%, with a dental origin in 35.5% of cases, mainly represented by dental infection in exclusive mandibular locations. More than 90% of patients were partially or completely dentate, and more than 70% had poor oral hygiene. Dental extractions were performed in 67.9% of patients before radiotherapy and in 42.9% after radiotherapy. Statistically significant risk factors associated with time-to-ORN were addictions (tobacco and alcohol), diabetes, oropharyngeal tumour location, combination of surgery followed by radiotherapy and post-radiotherapy dental extractions.

DISCUSSION AND CONCLUSION

Considering that ORN implies severe disabilities and complex management, the rate of 7.5% is unacceptable. A better dental prevention could reduce this rate by one-third. Dental extractions could be systematic in high-dose irradiation mandibular areas in patients presenting with poor oral hygiene and/or statistically significant risk factors for the occurrence of ORN. Moreover, favourable oral condition after radiotherapy should be maintained.

Bone microarchitecture and turnover in the irradiated human mandible

OBJECTIVES

The aim of this study was to assess the microarchitecture and turnover in irradiated cancellous mandibular bone and the relation with radiation dose, to elucidate the effects of radiotherapy on the mandible.

PATIENTS AND METHODS

Mandibular cancellous bone biopsies were taken from irradiated patients and controls. Micro-CT scanning was performed to analyze microstructural bone parameters. Bone turnover was assessed by histomorphometry. Local radiation dose at the biopsy site (Dmax) was estimated from radiotherapy plans.

RESULTS

Twenty-seven irradiated patients and 35 controls were included. Osteoid volume (Osteoid Volume/Bone Volume, OV/BV) [0.066/0.168 (median/interquartile range (IQR), OV/BV; %), P < 0.001], osteoid surface (Osteoid Surface/Bone Surface, OS/BS) [0.772/2.17 (median/IQR, OS/BS; %), P < 0.001] and osteoclasts number (Osteoclasts per millimetre bone surface, Ocl/mmBS; mm²) [0.026/0.123 (median/IQR, Ocl/mmBS; mm²), P < 0.001] were decreased; trabecular number (Tb.N) was lower [1.63/0.63 (median/IQR, Tb.N; 1/mm^-1), P = 0.012] and trabecular separation (Tb.Sp) [0.626/0.24 (median/IQR, Tb.Sp; μm), P = 0.038] was higher in irradiated mandibular bone. With higher Dmax, trabecular number increases (Spearman's correlation R = 0.470, P = 0.018) and trabecular separation decreases (Spearman's correlation R = -0.526, P = 0.007). Bone mineral density (BMD, milligrams hydroxyappetite per cubic centimetre, mgHA/cm³) [1016/99 (median/IQR, BMD; mgHA/cm³), P = 0.03] and trabecular separation [0.739/0.21 (median/IQR, Tb.Sp; μm), P = 0.005] are higher whereas connectivity density (Conn Dens) [3.94/6.71 (median/IQR, Conn Dens), P = 0.047] and trabecular number [1.48/0.44 (median/IQR, Tb.N; 1/mm^-1), P = 0.002] are lower in Dmax ≤50 Gy compared to controls.

CONCLUSIONS

Radiotherapy dramatically impairs bone turnover in the mandible. Deterioration in microarchitecture only affects bone irradiated with a Dmax of <50 Gy. The 50 Gy value seems to be a critical threshold to where the effects of the radiation is more detrimental.

Hyperbaric oxygen therapy for radiation-induced tissue injury following sarcoma treatment: A retrospective analysis of a Dutch cohort

Background and objectives

Sarcomas are commonly managed by surgical resection combined with radiotherapy. Sarcoma treatment is frequently complicated by chronic wounds and late radiation tissue injury (LRTI). This study aims to gain insight in the use and results of hyperbaric oxygen therapy (HBOT) for radiation-induced complications following sarcoma treatment.

Methods

All sarcoma patients treated between 2006 and 2017 in one of the five centers of the Institute for Hyperbaric Oxygen in the Netherlands were included for retrospective analysis.

Results

Thirty patients were included, 18 (60.0%) patients were treated for chronic wounds and 12 (40.0%) for LRTI. Two patients with chronic wounds were excluded from analysis as HBOT was discontinued within five sessions. In 11 of 16 (68.8%) patients treated for chronic wounds, improved wound healing was seen. Nine of 12 (75.0%) patients treated for LRTI reported a decline in pain. Reduction of fibrosis was seen in five of eight patients (62.5%) treated for LRTI.

Conclusions

HBOT is safe and beneficial for treating chronic wounds and LRTI in the sarcoma population. Awaiting further prospective results, we recommend referring to HBOT centers more actively in patients experiencing impaired wound healing or symptoms of delayed radiation-induced tissue injury following multimodality sarcoma treatment.