Racial differences in bone density variation in head and neck cancer patients with osteoradionecrosis: A pilot study.

OBJECTIVES

This study aimed to assess pre- and post-radiation therapy mandibular bone densities in head and neck cancer patients with osteoradionecrosis and factors associated with decreased bone densities.

METHODS

Retrospective pilot study (2007-2017) of osteoradionecrosis patients after 66- to 70-gray radiation therapy. Cortical and cancellous mandibular bone densities ipsilateral/contralateral to tumour were measured on pre-radiation therapy and at three-month and one-year post-radiation therapy positron emission tomography/computed tomography. Two-way analysis of variance and linear regression were used as exploratory analyses, given the pilot nature of the study.

RESULTS

Sixteen of 67 head and neck cancer patients had osteoradionecrosis (41-67 years of age; nine African Americans, seven Caucasians). Bone density did not significantly change from baseline within either racial group. African Americans had higher bone densities than Caucasians (pre-radiation therapy ipsilateral cortical: 1044 ± 229.8 vs. 965.6± 278.7 Hounsfield units). At one year, African Americans had higher contralateral cortical (+35.5 per cent; p = 0.008) and cancellous (+109.4 per cent; p = 0.028) bone densities. Multivariable models showed lower contralateral cortical (p = 0.039) and cancellous (p = 0.005) bone densities in Caucasians.

CONCLUSION

In this small pilot study, mandibular bone densities appeared higher in African Americans, with a greater post-radiation therapy reduction observed in Caucasians; these findings are exploratory and require validation in larger cohorts.