Analysis of the critical dose of radiation therapy in the incidence of Osteoradionecrosis in head and neck cancer patients: a case series

Risk factors associated with the development of osteoradionecrosis (ORN) in Head and Neck cancer patients in Ireland: A 10-year retrospective review

BACKGROUND AND PURPOSES

To assess osteoradionecrosis (ORN) incidence in a population of Irish Head and Neck cancer (HNC) patients, and assess precipitating factors that may contribute to ORN development to aid prevention.

MATERIALS AND METHODS

Review of 1050 HNC patients attending the Dental Oncology Clinic, CUDSH between 2010 and 2021 identified 47 cases of ORN. Medical, dental and radiotherapy records of these forty-seven patients were retrospectively reviewed. Patient-, tumour-, and treatment-related variables were investigated in association with osteoradionecrosis development. Analysis conducted using SPSS, Pearson's Chi-square test (p < 0.05), and ordinal regression model.

RESULTS

ORN incidence was 4.4 %. Median time from radiotherapy (RT) to ORN development was 9.5 months (range 1-98.5 months). ORN development within the mandibular surgical site was significant (p <.001), presenting at a higher Notani grade (p =.002), in mid-mandibular body region (p =.028), at radiation doses ≥ 60 Gy (p =.035), due to induced causes (p =.029), and without resolution (p =.019).

CONCLUSION

This is the first retrospective study of ORN in HNC patients in Ireland over 10-year period. ORN incidence was extremely low (4.4%). As patients reported high smoking/alcohol use and poor dental attendance pre-diagnosis, this suggests intensive dental intervention pre/post-diagnosis contributed to low ORN rates. Mandibular surgery pre-RT increased risk of developing ORN at the surgical site. Therefore, we recommend future treatment planning should contour the surgical site, designating it an organ at risk (OAR), assigning a dose constraint, where oncologically possible, with emphasis on reducing the hot-spot to this region; findings reinforce importance of life-long expert dental care to reduce ORN incidence.

Retrospective study evaluating dental side effects of radiotherapy in patients treated for head and neck cancer

INTRODUCTION

Head and neck cancer squamous cell carcinoma (HNSCC) is the seventh most common cancer worldwide with around 600,000 new diagnosis each year. Nowadays, in locally advanced disease, radiotherapy (RT) play an important role, this with or without chemotherapy in organ preservation strategies. More specific for early stage localized disease, RT (or surgery) seems to give similar results on locoregional control (LRC) and choice is made according to the organ preservation issue. Despite the fact that technical improvements have been made to optimize the radiation dose delivery and minimize the normal tissue toxicity, RT is associated with potential early and late toxicities. Osteoradionecrosis of the jaw (ORNJ), especially seen after teeth extraction, is one of the associated toxicities and can significantly impair the patient's quality of life. Because of the fear of developing ORNJ, one is very reluctant to extract or place a dental implant post-radiotherapy, especially in high irradiation dose zones (>40 Gy). Hence, it is important to define teeth at risk of future extraction before initiating RT and to handle those in high-risk irradiation zones. In order to optimise extractions, we created a predictive model of the expected irradiation dose, and thus the need for extraction, to the teeth bearing bones. The aim of this study is to validate our model and to define the potential relationship between the radiation dose received by each tooth and the dental complications observed.

MATERIAL AND METHODS

Between March 2012 and March 2018, patients with HNSCC treated by intensity modulated RT were retrospectively analysed. The mean irradiation dose for each tooth was generated on the administered treatment plan by contouring each tooth separately on each dosimetric scan section using dedicated software (Eclipse, Varian). In order to validate our predictive model, we compared the actual generated/administered teeth irradiation doses with the irradiation doses predicted by our model.

RESULTS

Our predictive model was accurate in 69.6% of the cases. In 12.5% of cases the predicted dose was higher than the calculated dose and lower in 17,8% of the cases. A correct- or over-estimation (is the latter being clinically less worrying than an underestimated dose) was achieved in 82% of cases. For the 18% of cases underfitting, the mean margin of error was 5.7 Gy. No statistically significant association was found between the development of caries and doses to the teeth, doses to the parotid glands or dental hygiene. However, a significant association between dental irradiation at more than 40 Gy and the occurrence of dental fractures (p = 0.0002) were demonstrated.

CONCLUSIONS

Our predictive model seems to be 82% accurate for dose prediction, hence might be helpful for optimizing/minimizing prophylactic extractions. Indeed, following our model, professionals could decide not to extract damaged teeth in areas not at risk of ORNJ, lowering morbidity during and after RT. Contrary to the literature, no relationship was found between the occurrence of dental caries and parotid irradiation and the patient's oral hygiene. However, for the first time, a highly significant correlation between the occurrence of dental fracture and dental irradiation at more than 40 Gy was observed.

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.

Advances and Controversies in the Management of Osteoradionecrosis After Head and Neck Cancer Treatment: A Narrative Review

Osteoradionecrosis (ORN) is a painful and debilitating serious late complication following treatment for head and neck cancer (HNC) often requiring surgical resection of the jaw and complex multidisciplinary management. An important aggravating factor for mandibular ORN is surgical trauma, commonly dental extractions or implant placement following head and neck radiotherapy. The evidence on the treatment protocols ranges from conservative management to more radical surgical strategies including the use of hyperbaric oxygen therapy. The available evidence on the preventive approaches for ORN includes prophylactic dental care prior to radiotherapy, the use of hyperbaric oxygen (HBO) treatment and prophylactic antibiotics for post-radiotherapy extractions. However, the efficacy of hyperbaric oxygen therapy has been questioned recently signifying poor understanding of the pathophysiology of the condition and therapies targeting the fibroatrophic process have become a focus of ORN treatment. Implementing recent IMRT radiation techniques has also shown evidence to reduce the incidence of ORN. This review provides an insight into the variations in definition and classification of the ORN, the controversies in its pathophysiology and the advances in the prevention and management.

Unforeseen Outcomes Post Treatment for Radiation Induced Trismus: A Case Report

Post radiotherapy radiation trismus presents significant concerns for a patient’s quality of life and for the clinical monitoring for recurrence of head and neck oncology. Current treatments include scar band release surgery that has been shown to be safe and effective. We present a case with a rare, post-operative complication of difficulty of mouth closure that can pose a significant impact on quality of life that should be considered.

Conservative orthodontic treatment for severe pathologic migration following total glossectomy: A case report

Glossectomy combined with radiotherapy causes different levels of tongue function disorders and leads to severe malocclusion, with poor periodontal status in cancer survivors. Although affected patients require regular access to orthodontic care, special considerations are crucial for treatment planning. This case report describes the satisfactory orthodontic management for the correction of severe dental crowding in a 43-year-old female 6 years after treatment for tongue cancer with total glossectomy combined with radiotherapy, to envision the possibility of orthodontic care for oral cancer survivors. Extraction was performed to correct dental crowding and establish proper occlusion following alignment, after considering the possibility of osteoradionecrosis. Orthodontic mini-implants were used to provide skeletal anchorage required for closure of the extraction space and intrusion of the anterior teeth. The dental crowding was corrected, and Class I occlusal relationship was established after 36 months of treatment. The treatment outcome was sustained after 15 months of retention, and long-term follow-up was recommended.

BDJ Open (2019-2020) and the advantages of open access publishing

BDJ Open is the open access sister journal to the British Dental Journal, and this paper aims to explore the various different articles that BDJ Open has published between 2019 and 2020, in order to highlight which areas authors felt were important to publish open access. Furthermore, this article will investigate the advantages of open access publishing to both authors and readers, as well as the scientific community in general, and will examine how open access publishing has allowed the BDJ Portfolio to publish a wide range of research, both in terms of topic and geography.

Examines papers published in BDJ Open between 2019 and 2020 to highlight which areas researchers felt were important to publish open access.

Discusses the advantages of open access publishing to authors, readers and the scientific community.

Explores how open access publishing has allowed the BDJ Portfolio to publish a far wider range of research both geographically and subject-wise.