Computed tomography bone density variations in oncological patients undergoing antiresorptive medication

BACKGROUND: The purpose of this study was to compare jaw and cervical vertebrae bone density in computed tomography (CT) analyses of oncological patients undergoing antiresorptive medication with control patients, aiming to find information that may assist the radiologist and clinician in predicting risks and monitoring osteonecrosis in the jaw. MATERIAL AND METHODS: Thirty-one patients treated with zoledronic acid and 37 control were included in the study. Two areas in regions of interest were chosen and standardized, one in the lower portion of the mandible and another in the axial cervical vertebra (C2) of patients undergoing antiresorptive drug treatment (experimental group) and the control group. Density analysis was performed using Hounsfield scale grayscale values obtained from multislice CT exams. Interclass correlation coefficient test (ICC) was performed to assess reproducibility and repeatability. The test of normality of the samples was demonstrated using the Shapiro-Wilk test and the comparison performed using Mann-Whitney U non-parametric test. RESULTS: When compared to patients in the control group, patients undergoing antiresorptive medication depicted an increase in bone density in both jaw bone (p=0.021) and cervical vertebrae (p=0.002). The same pattern could be observed in patients who used the medication on a monthly basis for analysis of jaw bone (p=0.021), the cervical vertebrae (p=0.002), and the cervical vertebrae of the patients who used the medication on a quarterly basis (p=0.003). CONCLUSIONS: CT can be a potentially useful method for detecting alterations associated with antiresorptive therapy, serving as a possible tool in the prediction of the disease progression. Key words:Bone density, computed tomography, bisphosphonate osteonecrosis, jaw, cervical vertebrae.