The efficacy of positioning stents in preventing Oral complications after head and neck radiotherapy: a systematic literature review

Post-radiation xerostomia therapy with allogeneic mesenchymal stromal stem cells in patients with head and neck cancer: study protocol for phase I clinical trial

BACKGROUND

Xerostomia is a common side effect of radiotherapy in patients with head and neck tumors that negatively affects quality of life. There is no known effective standard treatment for xerostomia. Here, we present the study protocol used to evaluate the safety and preliminary efficacy of allogeneic mesenchymal stromal stem cells (MSCs) derived from umbilical cord tissue.

PATIENTS AND METHODS

Ten oropharyngeal cancer patients with post-radiation xerostomia and no evidence of disease recurrence 2 or more years after (chemo)irradiation (intervention group) and 10 healthy volunteers (control group) will be enrolled in this nonrandomized, open-label, phase I exploratory study. MSCs from umbilical cord tissue will be inserted under ultrasound guidance into both parotid glands and both submandibular glands of the patients. Toxicity of the procedure will be assessed according to CTCAE v5.0 criteria at days 0, 1, 5, 28, and 120. Efficacy will be assessed by measuring salivary flow and analyzing its composition, scintigraphic evaluation of MSC grafting, retention, and migration, and questionnaires measuring subjective xerostomia and quality of life. In addition, the radiological, functional, and morphological characteristics of the salivary tissue will be assessed before, at 4 weeks, and at 4 months after the procedure. In the control group subjects, only salivary flow rate and salivary composition will be determined.

DISCUSSION

The use of allogeneic MSCs from umbilical cord tissue represents an innovative approach for the treatment of xerostomia after radiation. Due to the noninvasive collection procedure, flexibility of cryobanking, and biological advantages, xerostomia therapy using allogeneic MSCs from umbilical cord tissue may have an advantage over other similar therapies.

Oral health in patients with different sites of head and neck squamous cell carcinoma is not different

Oral health might not only act as risk factor for head and neck squamous cell carcinoma (HNSCC), but might also have a predictive value for the patients' survival. Currently, information on the effect of oral health on survival of patients with different sites of HNSCC is lacking. This single-center retrospective study aimed to compare oral health in patients with different sites of HNSCC and to analyse whether oral health is associated with survival in the different subsets of HNSCC patients. Dental records of HNSCC patients referred for dental assessment prior to radio(chemo)therapy were included. Patient-related parameters (age at time of diagnosis, sex, tobacco exposure, alcohol consumption, HPV status), treatment data (primary treatment, intent), performance status, tumor demographics (anatomical site, TNM staging), and oral health parameters (DMFT, periodontal health, teeth with/without root canal treatment and with/without periodontitis apicalis) were obtained. Oral health parameters were compared between different anatomical sites. Survival of all HNSCC patients and of individual subsets was assessed using Kaplan-Meier statistics, and the effect of tumor demographics, patient-related parameters, and oral health on survival was analysed by cox regression analyses (α = 5%). 371 patients with HNSCC (oral: n = 86, oropharyngeal: n = 174, hypopharyngeal: n = 59, laryngeal: n = 15, other: n = 37) were included. Oral health parameters did not differ between subsets (padj.≥0.199). Five-year cumulative survival of HNSCC patients amounted to 78.6%. Only for HNSCC originating in the oral cavity and oropharynx, survival was associated with the treatment intent (p = 0.015) or performance status (p = 0.007) in the multivariable analyses, respectively. Within the limitations of this study, oral health was not different between different subsets and had no significant effect on survival of HNSCC patients.

Current management of xerostomia in head and neck cancer patients

Radiotherapy (RT) continues to play a key role in the management of head and neck cancer (HNC). Xerostomia remains a principal detriment to the quality of life (QoL) for 80 % of surviving patients receiving head and neck radiation. Radiation-induced injury to the salivary glands is dose-dependent, and thus efforts have been focused on decreasing radiation to the salivary glands. Decreased saliva production reduces both short-term and long-term quality of life in head and neck survivors by impacting on taste and contributing to dysphagia. Several radioprotective agents to the salivary gland have been investigated. Although not widely practiced, surgical transfer of the submandibular gland prior to RT is the mainstay of surgical options in preventing xerostomia. This review focuses on the strategies to improve xerostomia following radiation therapy in head and neck cancers.

Digital fabrication of customized intraoral appliances for head and neck radiotherapy

Introduction

The radiotherapy received by head and neck cancer patients commonly has adverse effects on oral tissue and the muscles of mastication. This short communication describes the digital fabrication of intraoral appliances for radiotherapy and muscle exercises.

Methods

Three patients diagnosed with tongue squamous carcinoma were treatment-planned for radiotherapy using different radiation techniques. The patients were referred for oral scanning and digital bite records, and the appliance was collaboratively designed by a radiation oncologist, dentist, and laboratory technician. The appliance covered the occlusal surface of the remaining teeth with a 1-mm engagement. The lingual plate was 2-mm below the occlusal plane, and extended 4-mm distally, and the jaws were opened by 20-mm. The appliances were printed overnight using a rigid and biocompatible 3D printing material.

Results

Requiring minimal chair-time, the appliance was easily inserted and adjusted to comfortably fit in the mouth. The patients were trained to insert it themselves. The tongue was at a pre-determined position during daily radiotherapy, and the healthy tissues were separated from the radiation field. The patients had mild adverse effects on their oral mucosa. Additionally, the appliances were used for muscle exercises after the radiation courses to prevent trismus.

Conclusions

The interprofessional collaboration to fabricate customized intraoral appliances using digital workflow to maximize patients' benefits is feasible.

Clinical significance

The use of intraoral appliances is potentially increased when the fabrication process is facilitated. Using an intraoral appliance precisely targets the tumor are for better treatment outcomes, and the healthy adjacent tissues will be preserved to maintain the patient's quality of life.

Consideration of mouth opening when using positioning stents during radiotherapy for tongue cancer: a retrospective study

Background

The aim was to clarify the range of mouth opening required to minimize the development of oral mucositis on the palate while using a positioning stent during radiotherapy in patients with tongue cancer. A positioning stent is used to reduce the severity of oral mucositis; however, requirements for fabricating the device have not been standardized. In particular, the range of mouth opening required while using a stent to prevent radiation-induced oral mucositis has not been determined.

Materials and methods

We retrospectively analyzed medical records and computed tomography (CT) images of nine patients who had undergone radiotherapy for tongue cancer. Irradiation dose for the palate and range of mouth opening while using the positioning stent was calculated from CT images and the radiotherapy treatment planning program.

Results

The irradiation dose presented as medians and interquartile range (IQR) for the palate was 1.6 (IQR: 1.1-2.2) Gy with the use of the positioning stent and 37.2 (IQR: 17.5-44.1) Gy without the use of the positioning stent. The range of mouth opening was 19-37 [mean ± standard deviation (SD): 26 ± 5.6] mm, and it correlated with the attenuation amount of irradiation dose to the palate (r = 0.673, p = 0.0467). Regression equation was y = 0.21x + 19.

Conclusions

Our study may be useful for deriving the relationship between the attenuation amount of irradiation of the palate with the positioning stent and the amount of mouth opening required for this attenuation.

Evaluation of radiodensity and dimensional stability of polymeric materials used for oral stents during external beam radiotherapy of head and neck carcinomas

Purpose

Intraoral stents protect the healthy tissues from ionizing radiation during external beam radiotherapy reducing mucositis, hyposalivation and osteoradionecrosis. This study investigated the radiodensity and dimensional stability of polymeric materials for suitability in construction of intraoral stents and aimed to provide clinical guidelines.

Methods

Specimens were fabricated using 4 material types namely, resin composite (ProTemp-PRO), polymethylmethacrylate (PMMA) (Enamel Temp Plus-ETP, Palapress-PAL, TAB 2000-TAB), polycaprolactone (Orfit-ORF) and silicone (Adisil-ADI, Lab Putty-LAB, Memosil2-MEM, Optosil-OPT, President Plus-PRE, Siolaplast A-SIA). They were randomly assigned to measure their radiodensity in Hounsfield Units (HU) (12x12x11mm³) (N_radiodensity = 66; n = 6) using a computer tomograph (CBCT, Toshiba Aquillon LB scanner) at baseline and after 6 weeks. The scanning protocol was applied with and without single energy metal artifact reduction (SEMAR) scans using a slice thickness of 1 and 5 mm. The same materials have been tested for their dimensional stability (µm³) at baseline, 1, 6, 12, 24 h, 3 and 6 weeks (14 × 4 × 2 mm³) (N_dimension = 55; n = 5 per material) using stereolithography (STL) files generated by a lab scanner (L2i, Imetric4D, Courgenay, Switzerland) and analyzed using a matching software (Geomagic ControlX 2020, 3D Systems). Data were analyzed using a paired t-test (alpha = 0.05).

Results

Radiodensity values (HU) were significantly affected by the material classification (p < 0.05). Polycaprolactone (43.6) presented significantly lower HU values followed by PMMA (91.3-414.9) than those of silicone materials (292.8-874.5). In terms of dimensional stability (µm³), PMMA materials (Δ:1.53-2.68) and resin composite (Δ:2.89) were significantly more dimensionally stable compared to those of silicone materials (Δ:13.64-6.63) and polycaprolactone (Δ:-0.76) and (p < 0.05).

Conclusion

For fabricating intraoral stents, when reduced radiodensity values are required polycaprolactone could be recommended as it fulfils the requirements for reduced radiodensity and dimensional stability. Among all silicone materials, OPT and MEM can be recommended based on the low HU and dimensional stability.

Development of a customisable 3D-printed intra-oral stent for head-and-neck radiotherapy

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Advanced radiotherapy techniques have improved head-and-neck treatments.

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More improvements are possible with intra-oral stents stabilising sensitive anatomy.

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MRI imaging shows new modular 3D printed stents provide stable displacement.

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Modular stents achieve positive outcomes within standard treatment workflow.

Intra-oral stents (including mouth-pieces and bite blocks) can be used to displace adjacent non-involved oral tissue and reduce radiation side effects from radiotherapy treatments for head-and-neck cancer. In this study, a modular and customisable 3D printed intra-oral stent was designed, fabricated and evaluated, to utilise the advantages of the 3D printing process without the interruption of clinical workflow associated with printing time. The stent design used a central mouth-opening and tongue-depressing main piece, with optional cheek displacement pieces in three different sizes, plus an anchor point for moulding silicone to fit individual patients’ teeth. A magnetic resonance imaging (MRI) study of one healthy participant demonstrated the tissue displacement effects of the stent, while providing a best-case indication of its comfort.

State of Rehabilitation Research in the Head and Neck Cancer Population: Functional Impact vs. Impairment-Focused Outcomes

PURPOSE OF REVIEW

Management of head and neck cancer (HNC) typically involves a morbid combination of surgery, radiation, and systemic therapy. As the number of HNC survivors grows, there is growing interest in rehabilitation strategies to manage HNC-related comorbidity. In this review, we summarize the current state of HNC rehabilitation research.

RECENT FINDINGS

We have organized our review using the World Health Organization's International Classification of Function (ICF) model of impairment, activity, and participation. Specifically, we describe the current research on rehabilitation strategies to prevent and treat impairments including dysphagia, xerostomia, dysgeusia, dysosmia, odynophagia, trismus, first bite syndrome, dysarthria, dysphonia, lymphedema, shoulder syndrome, cervicalgia, cervical dystonia and dropped head syndrome, deconditioning, and fatigue. We also discuss the broader impact of HNC-related impairment by exploring the state of rehabilitation literature on activity, participation, psychosocial distress, and suicidality in HNC survivors. We demonstrate that research in HNC rehabilitation continues to focus primarily on impairment-driven interventions. There remains a dearth of HNC rehabilitation studies directly examining the impact of rehabilitation interventions on outcomes related to activity and participation. More high-quality interventional studies and reviews are needed to guide prevention and treatment of functional loss in HNC survivors.

Osteosarcoma of the jaws: An overview of the pathophysiological mechanisms

Osteosarcoma (OS) is the most common cancer of bone. Jaw osteosarcoma (JOS) is rare and it differs from long-bone OS (LBOS) in terms of the time of onset (two decades later), lower metastatic spread, and better survival. OS is characterized by the proliferation of osteoblastic precursor cells and the production of osteoid or immature bone. OS arises from a combination of genetic aberrations and a favourable microenvironment. This local microenvironment includes bone cells, blood vessels, stromal cells, and immune infiltrates, all of which may constitute potential targets for anti-cancer drugs. Differences in the clinical and biological behaviour of JOS versus LBOS are likely to at least in part be due to differences in the microenvironment between the two sites. The present review provides a brief overview of the known pathophysiological parameters involved in JOS.