Timing of development of osteoradionecrosis post head and neck radiotherapy: does a safe time interval exist for dental extraction?

INTRODUCTION: Risk factors for developing osteoradionecrosis (ORN) are well known, but less is known about factors influencing the interval between radiotherapy and the onset of ORN. Also, it is unknown whether there is any specific period post-radiotherapy with a reduced probability of ORN when irradiated teeth require extraction. PURPOSE: The primary aim of this study was to identify factors influencing the interval in developing ORN in the following subgroups of patients: (1) patients who spontaneously developed ORN, (2) surgical-intervention-related ORN with a particular focus on patients after mandibulectomy. The secondary aim was to attempt to identify a possible time for safer dental intervention after primary treatment. MATERIALS AND METHODS: The authors retrospectively analysed 1608 head and neck cancer (HNC) patients treated in a single centre. Time intervals were measured from the end of radiotherapy to the development of ORN and further analysed in the subgroups listed above. RESULTS: In all, 141 patients (8.8%) developed intra-oral ORN. Median time from radiotherapy to ORN development in the whole cohort was 9 months. Median interval for spontaneous ORN was 8 months, 6.5 months for intervention-related ORN, and 15 months for patients post-mandibulectomy. In patients who required dental extraction preradiotherapy, median interval of ORN onset was 5 months. CONCLUSION: In our study, a slightly higher proportion of patients with intervention developed ORN earlier in comparison with spontaneous ORN. The period from 12-18 months after radiotherapy was identified as having the highest probability of developing ORN in patients after mandibulectomy. A time for safer dental intervention after primary treatment was not identified.

Metastatic spinal cord compression: the Spinal Instability Neoplastic Score and early surgical intervention.

OBJECTIVES: To evaluate the value of Spinal Instability Neoplastic Score (SINS) in patients with spine metastasis who subsequently developed or did not develop metastatic spinal cord compression (MSCC). METHODS: In this single institutional retrospective descriptive observational study, of 589 patients with MSCC who were referred for radiotherapy, 34 patients (with 41 compression sites) met the inclusion criteria: availability of diagnostic MRI spine pre-development of MSCC (MRI-1) and at the time of MSCC development (MRI-2) (CordGroup).For comparison, NoCordGroup consisted of 152 patients (160 sites) treated with radiotherapy to spinal metastases. SINS was compared between the two groups. RESULTS: In CordGroup, the median interval between MRI-1 and MRI-2 was 11 weeks. The median SINS was 8 (range: 4-14) and 9 (range: 7-14) on MRI-1 and MRI-2, respectively. In NoCordGroup, the median SINS was 6 (range: 4-10). CONCLUSIONS: Our study showed a trend in difference in SINS value between the two groups. This difference should be a subject of future prospective research in this patient population with poor survival.

Dental loss after radiotherapy for head and neck cancer.

Introduction In radiotherapy (RT) for head and neck cancer (HNC), dental morbidity is significant and it may result in loss of the dentition following treatment.Aims The aim of this clinical study is to identify the incidence of tooth loss over time and correlate this to the RT dose and various risk factors in patients with HNC treated with radical RT.Design A retrospective observational study.Materials and methods The records of 1,118 patients with HNC treated with radical or adjuvant RT from January 2010 to December 2019 were analysed. After applying strict inclusion criteria, 78 patients with 1,566 individual tooth data were selected. RT dose mapping was performed for each tooth.Results A total of 253 teeth (16.2%) were extracted. The following risk factors were significant: gender (p = 0.0001), xerostomia (p <0.0001), RT dose (p <0.0001) and smoking (p <0.0001). Non-significant factors were age, RT delivery technique and the addition of cisplatin.Conclusion Detailed RT dose mapping was used to identify RT dose as a risk factor for dental loss. Careful pre-RT dental treatment and minimisation of RT dose to teeth and salivary glands is required to prevent or reduce the loss of dentition.