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

The incidence of osteoradionecrosis of the jaws in oral cavity cancer patients treated with intensity-modulated radiotherapy: a systematic review and meta-analysis

OBJECTIVE

A systematic review with meta-analysis was conducted to define the incidence of osteoradionecrosis (ORN) in patients with oral cavity cancer (OCC) treated with intensity-modulated radiotherapy (IMRT), and to identify the risk factors influencing its development.

STUDY DESIGN

Six databases were searched systematically. A meta-analysis was performed to determine overall, spontaneous, and dental extraction-attributed incidences of ORN. The Grading of Recommendations Assessment, Development, and Evaluation tool evaluated evidence certainty.

RESULTS

Out of 11 eligible studies, 6 underwent meta-analysis for the overall aggregated ORN incidence in OCC patients receiving IMRT, resulting in an incidence rate of 8% (95% CI: 6%-11%). Regarding development reasons, 2 studies were assessed, revealing an incidence of 36% (95% CI: 1%-98%) for spontaneous ORN, and 17% (95% CI: 5%-44%) ensued from dental extraction exclusively pre-RT. All rates had very low certainty of evidence. Factors significantly correlated with ORN development included postoperative RT use (78%), employment of therapeutic doses above 50 Gy, and mandibular involvement (80.5%).

CONCLUSION

The findings suggest that IMRT alone is not sufficient to decrease ORN rates in OCC patients, underscoring the importance of precisely identifying the involved risk factors. However, further detailed primary studies will be necessary.

Osteoradionecrosis Rates After Head and Neck Radiation Therapy: Beyond the Numbers

PURPOSE

Osteoradionecrosis (ORN) is a severe late complication of head and neck radiation therapy shown to have profound negative effect on the quality of life of cancer survivors. Over the past few decades, improvements in radiation delivery techniques have resulted in a decrease in the incidence of ORN. However, even with modern radiation therapy techniques, ORN remains an important clinical concern. In recent literature, there is a wide range of reported ORN rates from 0% to as high as 20%. With such a high level of variability in the reported incidence of ORN, oncologists often encounter difficulties estimating the risk of this serious radiation therapy toxicity.

METHODS AND MATERIALS

In this review, the authors present a summary of the factors that contribute to the high level of variability in the reported incidence of ORN.

RESULTS

Variable definition, variable grading, and heterogeneity of both study inclusion criteria and treatment parameters can each significantly influence the reporting of ORN rates.

CONCLUSIONS

Given numerous factors can affect the reported incidence of ORN, a thorough understanding of the clinical context behind the reported ORN rates is needed to comprehend the true risk of this important radiation therapy toxicity.

Osteoradionecrosis - an old problem with new consequences

PURPOSE OF REVIEW

Osteoradionecrosis (ORN) is a devasting complication of radiation therapy (RT), especially in head and neck cancers (HNC), and is still poorly understood. The aim of this review is to report its incidence and consider the risk factors associated with ORN to highlight prevention strategies to decrease its incidence.

RECENT FINDINGS

The average incidence of ORN is between 2% and 23%, with incidence decreasing in more recent years with the introduction of modern RT technology and better oral health care. Smoking, diabetes mellitus, oropharyngeal and oral cavity cancers, pre- and post-RT dental extractions and a total radiation dose of over 60 Gy were all identified as risk factors for ORN. In prevention, strategies were mainly structured around minimising risk factors or targeting possible mechanisms of ORN's pathophysiology.

SUMMARY

At present, the controversy surrounding the risk factors and pathogenesis of ORN makes it difficult to establish a set of prevention guidelines for its incidence. In order to achieve this, more research examining its aetiology must be conducted as well as a universal staging system within which ORN may be classified.

Tooth extraction within 2 weeks before radiotherapy and osteoradionecrosis: A nationwide cohort study

OBJECTIVES

The theory of at least 2-week waiting period between tooth extraction and head and neck radiotherapy could reduce osteoradionecrosis remains controversial. Thus, this study examined the theory and associated factors.

MATERIALS AND METHODS

Data were retrieved from the National Health Insurance Research Database, Taiwan Cancer Registry Database, and Cause of Death Statistics. We included 24,353 patients with head and neck cancer who received radiotherapy from 2011 to 2017 and were followed up until 2019. The patients were divided into three groups: those undergoing tooth removal 2-8 weeks before radiotherapy, those undergoing tooth removal within 2 weeks before radiotherapy, and others. Confounding factors were clinical information, physical conditions, and risky habits. We used the Cox regression model to assess osteoradionecrosis risk.

RESULTS

No significant difference in osteoradionecrosis risk was observed between those undergoing tooth extraction within 2 weeks before radiotherapy and the other groups. An irradiation dose of ≥60 Gy, chemotherapy, tumor excision, post-radiotherapy tooth extraction, mandibulectomy, hyperlipidemia, and oral cavity as the tumor subsite were significantly positively associated with osteoradionecrosis risk.

CONCLUSION

A waiting period of ≥2 weeks between tooth extraction and radiotherapy did not significantly reduce osteoradionecrosis risk.

An umbrella review exploring the effect of radiotherapy for head and neck cancer patients on the frequency of jaws osteoradionecrosis

OBJECTIVE

Efforts have been made to reduce epidemiological indicators of osteoradionecrosis in patients with head and neck cancer over recent years. This umbrella review aims to synthesize the information of the systematic reviews/meta-analyses investigating the effect of radiotherapy in patients with head and neck cancer on the frequency of osteoradionecrosis and to identify and analyze the gaps in current scientific literature.

MATERIAL AND METHODS

A systematic review of systematic reviews with and without meta-analysis of intervention studies was conducted. Qualitative analysis of the reviews and their quality evaluation were performed.

RESULTS

A total of 152 articles were obtained, and ten of them were selected for the final analysis, where six were systematic reviews and four were meta-analysis. According to the guide Assessing the Methodological Quality of Systematic Reviews (Amstar), eight articles included were of high quality and two of medium quality. These descriptive systematic reviews/meta-analyses included a total of 25 randomized clinical trials, showing that radiotherapy has positive effects on the frequency of osteoradionecrosis. Even though a reduction in the incidence of osteoradionecrosis was observed back in the history, in systematic reviews with meta-analysis, overall effect estimators were not significant.

CONCLUSIONS

Differential findings are not enough to demonstrate that there is a significant reduction in the frequency of osteoradionecrosis in patients with head and neck cancer treated by radiation. Possible explanations are related to factors such as the type of studies analyzed, indicator of irradiated complication considered, and specific variables included in the analysis. Many systematic reviews did not address publication bias and did identify gaps in knowledge that require further clarification.

Association between tooth extraction during radiotherapy and the risk of osteoradionecrosis in patients with head and neck cancers

PURPOSE

It is commonly recommended that tooth extraction should be performed prior to radiotherapy (RT) in patients with head neck cancer to prevent osteoradionecrosis (ORN). However, doctors still occasionally encounter patients who require tooth extraction during RT. This study aimed to determine the risk of ORN in patients who undergo tooth extraction during RT.

METHODS

Data were collected from Taiwan's National Health Insurance Research Database. We retrospectively enrolled 24,412 patients with head and neck cancer treated with radiotherapy between 2011 and 2017. The associations between ORN and demographic characteristics, timing of tooth extraction, and treatments were examined using univariate and multivariable Cox proportional hazards regression models.

RESULTS

A total of 24,412 head and neck cancer patients were enrolled; 133 patients underwent tooth extraction during RT and 24,279 patients did not undergo tooth extraction during RT. Tooth extraction during RT was not associated with a significantly higher risk of ORN (hazard ratio [HR] = 1.303, P = 0.4862). Tumor site, RT dose ≥ 60 Gy, age < 55 y/o, mandibulectomy, chronic periodontitis, and chemotherapy were significantly associated with a higher risk of ORN.

CONCLUSION

The risk of ORN in head and neck cancer is not significantly different between patients who undergo tooth extraction during RT and patients who do not undergo tooth extraction during RT.

To extract or not extract teeth prior to head and neck radiotherapy? A systematic review and meta-analysis

PURPOSE

Teeth with poor prognosis are generally recommended to be extracted prior to head and neck radiotherapy (RT) to reduce the risk of developing osteoradionecrosis (ORN), although controversies have been reported. The present systematic review aimed to determine whether tooth extraction prior to head and neck RT may be associated with a reduced risk of developing ORN compared to dental extraction during or after RT.

METHODS

The review protocol was registered in PROSPERO (CRD42021241631). The review was reported according to the PRISMA checklist and involved a comprehensive search of PubMed, Scopus, Embase, Cochrane Library, LILACS, and Web of Science, in addition to the gray literature. The selection of studies was performed in two phases by two reviewers independently. The risk of bias of individual studies was analyzed using the Joanna Briggs Institute checklist for cross-sectional studies, and the certainty of evidence was assessed using the GRADE tool.

RESULTS

Twenty-eight observational studies were included in the qualitative synthesis, which showed substantial heterogeneity regarding the association between the timing of tooth extraction and ORN development. Twenty-seven of 28 studies were pooled in a meta-analysis that demonstrated a significant association between an increased risk of ORN and post-RT tooth extraction (odds ratio: 1.98; 95% CI: 1.17-3.35; p = 0.01).

CONCLUSION

It was confirmed with moderate certainty that dental extractions should be performed prior to the start of head and neck RT to reduce the risk of ORN.

Osteoradionecrosis after postoperative radiotherapy for oral cavity cancer: A retrospective cohort study

OBJECTIVE

Osteoradionecrosis (ORN) is a severe late complication after radiotherapy but current knowledge on ORN risks in the setting of postoperative radiotherapy (PORT) is limited. We studied the incidence and risk factors of ORN in patients with oral cavity cancers (OCC, treated with PORT.

PATIENTS AND METHODS

A retrospective cohort study was conducted including OCC patients (mainly squamous cell) treated with postoperative intensity modulated radiotherapy between 2010 and 2018 with > 1 year disease-free survival. Cumulative incidences of ORN were computed using the Kaplan Meier method. Clinical and dosimetric risk factors for mandibular ORN were evaluated using Cox regression models.

RESULTS

Within our cohort (N = 227, median follow-up 49 months) we observed 46 cases of ORN, mainly in the mandible (n = 41). The cumulative incidence of mandibular ORN was 15.9 % (SE 2.5 %) at three years and 19.8 % (SE 3.0 %) at five years. At univariable analysis, smoking, mandibular mandibulotomy or segment resection, mean dose to the mandible, and mandible volume (%) ≥ 60 Gy (V60) were significantly associated with increased ORN risks. At multivariable analysis, smoking (HR 2.13, 95 %CI 1.12-4.06) and V60 (HR 1.02 per 1 % increase, 95 %CI 1.01-1.04) remained predictive factors. For active smokers with a high V60 ≥ 40 % we observed rapid ORN development with a 1-year incidence of 29 % vs 6 % for others (p < 0.01).

CONCLUSION

OCC Patients treated with PORT are at high risk for mandibular ORN. We identified the mandibular volume receiving ≥ 60 Gy as the dominant risk factor, especially in active smokers. Limiting high-dose volumes at treatment planning may decrease ORN risks.

Progression and postoperative complications of osteoradionecrosis of the jaw: a 20-year retrospective study of 124 non-nasopharyngeal cancer cases and meta-analysis

BACKGROUND

To assess the contributing risk factors for the progression of, and the postoperative poor prognosis associated with, osteoradionecrosis of jaw (ORNJ) following non-nasopharyngeal cancer treatment in head and neck.

METHODS

A retrospective study of 124 non-nasopharyngeal carcinoma patients in head and neck treated at one institution between 2001 and 2020 was conducted. A cumulative meta-analysis was conducted according to PRISMA protocol and the electronic search was performed on the following search engines: PubMed, Embase, and Web of Science. After assessing surgery with jaw lesions as a risk factor for the occurrence of ORNJ, 124 cases were categorized into two groups according to the "BS" classification, after which jaw lesions, chemotherapy, flap reconstruction and onset time of ORNJ were analyzed through the chi-square test and t-test to demonstrate the potential association between them and the progression of ORNJ. Postoperative outcomes of wound healing, occlusal disorders, and nerve injury were statistically analyzed.

RESULTS

With the statistically significant results of the meta-analysis (odds ratio = 3.07, 95% CI: 1.84-5.13, p < 0.0001), the chi-square test and t-test were used to validate our hypotheses and identified that surgery with jaw lesions could aggravate the progression and accelerate the appearance of ORNJ. Patients who underwent chemotherapy tended to suffer from severe-to-advanced osteonecrosis but did not shorten the onset time of ORNJ. Flap reconstruction presented obvious advantages in wound healing (p < 0.001) and disordered occlusion (p < 0.005). The mean onset time of ORNJ in non-nasopharyngeal cancer patients (4.5 years) was less than that in patients with nasopharyngeal cancer (NPC) (6.8 years).

CONCLUSIONS

Iatrogenic jaw lesions are evaluated as a significant risk factor in the occurrence and progression of ORNJ in non-nasopharyngeal carcinoma patients who tend to have more severe and earlier osteonecrosis after radiotherapy than NPC patients. Flap reconstruction is a better choice for protecting the remaining bone tissue and reducing postoperative complications of ORNJ.

Oral Health Management and Rehabilitation for Patients with Oral Cancer: A Narrative Review

Surgery is the current first choice for oral cancer treatment. Intensity-modulated radiation therapy, molecular targeted drugs, and immune checkpoint inhibitors are still used as adjuvant therapy for advanced cancer. In addition, postoperative rehabilitation and multidisciplinary treatment have also been developed in recent years. Multidisciplinary team approaches and supportive care in oral cancer treatment reportedly shorten the time to treatment and improve outcomes. Although there is enough evidence confirming the role of oral and maxillofacial surgeons, dentists, and dental hygienists in supportive care in oral cancer treatment, there are very few systematic studies. In particular, oral health management is a concept that encompasses oral function management, oral hygiene management, and oral care during oral cancer treatment. We provide a narrative review focusing on oral health management from a multidisciplinary and supportive care perspective, applicable in oral cancer treatment.

Dental Evaluation Prior to Cancer Therapy

A comprehensive oral examination and dental care prior to the start of cancer therapy is the standard of care in many cancer centers. This is because good oral health will likely minimize the undesirable complications such as opportunistic infections during cancer therapy. As the considerations differ between anti-neoplastic regimens, this chapter discusses the indications and rationale when planning and executing a treatment plan for patients undergoing various cancer therapies.