Dose-volume correlates of mandibular osteoradionecrosis in Oropharynx cancer patients receiving intensity-modulated radiotherapy: Results from a case-matched comparison

Abstract

Purpose To determine dosimetric parameters associated with Osteoradionecrosis (ORN) in oropharyngeal cancer (OPC) patients in the IMRT era. Material and Methods Subsequent to institutional review board approval, we identified ORN in OPC patients treated with IMRT from 2002–2013. 1:2 case-control matching was implemented. Mandibular dose-volume histograms (DVH) were extracted. Dosimetric parameters were compared using non-parametric stats. Recursive partitioning analysis (RPA) was done to identify DVH correlates of ORN. Results 68 ORN cases and 131 controls were matched. Median follow-up was 41 months and median time to development of ORN was 16 months. Mandibular mean dose was significantly higher in the ORN cohort (48.1 vs 43.6 Gy, p < 0.0001). However, the maximum dose was not statistically different. DVH bins from V35 to V73 were all significantly higher in the ORN cohort compared with controls (p< 0.0006). Two DVH parameters were identified in RPA analysis, V43 and V58. The majority (81%) of ORN cases were observed with both V44≥42% and V58≥25%. Conclusions Our data demonstrate that a wide range of DVH parameters in the intermediate and high beam path were all significantly higher in ORN patients. Mandibular V44<42% and V58<25% represent reasonable DVH constraints for IMRT plan acceptability, when tumor coverage is not compromised.

Radiotherapy Controversies and Prospective in Head and Neck Cancer: A Literature-Based Critical Review

“…Consequently, it remains unclear which dosimetric parameters should be considered to minimize the ORN risk [24] . A recent case-matched comparison of only IMRT treated patients, showed that all doses in the intermediate and high range were more likely to be elevated in the ORN patients compared to asymptomatic controls [25] . These findings suggested that, to reduce ORN incidence, in IMRT treatment planning, whenever feasible, several volumetric constraints should be utilized, rather than a single point-dose maximum as in the pre-IMRT era.…”

Patients with head and neck cancers' oral health knowledge, oral health‐related quality of life, oral health status, and adherence to advice on discharge to primary dental care: A prospective observational study

“…Peterson et al reported the prevalence of established ORN as 7% with conventional radiotherapy and 5% with IMRT. A recent case‐matched comparison study of only IMRT treated oropharyngeal cancer patients showed that individuals in the ORN group had received higher doses of radiotherapy compared to asymptomatic controls . In our study, although all recruited patients were treated with IMRT, five (17%) and two (7%) patients had an established and new ORN, respectively.…”

“…A recent case-matched comparison study of only IMRT treated oropharyngeal cancer patients showed that individuals in the ORN group had received higher doses of radiotherapy compared to asymptomatic controls. 26 In our study, although all recruited patients were treated with IMRT, five (17%) and two (7%) patients had an established and new ORN, respectively. All seven participants with the ORN had cancer localized to the oral cavity where the mandible would have been included and would have received the maximum dose.…”

The Efficacy of a Custom-Made Mouthpiece With Spacer to Reduce Osteoradionecrosis in Carbon-Ion Radiation Therapy for Tongue-Base Tumor

“…With regard to photon RT, high-dose irradiation to the mandible has been reported previously as a risk factor for ORN. 11 , 12 The MD Anderson Head and Neck Cancer Symptom Working Group 12 reported the dosimetric parameters associated with ORN in 199 patients with oropharyngeal cancer treated with photon RT. In the study, the mandibular mean dose was significantly higher in the ORN cohort compared with the non-ORN cohort (48.1 vs 43.6 Gy; P < .0001).…”