Assessment of denosumab treatment efficiency in patients with giant cell tumor of bone using CT and MRI (own results and literature review)

Relevance. Giant cell tumor of the bone is most common in people of working age, which determines the high social significance of successful treatment of this category of patients. The main method of treatment is surgical. Currently, the targeted drug denosumab has appeared, the criteria for evaluating the effectiveness of therapy for which, according to the data of radiation methods, are not clearly defined.Target. To analyze and compare the possibilities of CT and MRI in evaluating the effectiveness of denosumab therapy for giant cell tumors.Materials and methods. The data of CT and MRI of 19 patients with giant cell tumor of tubular bones on the background of denosumab therapy were analyzed.Results. Before treatment, the extraosseous component was determined in 57.9 % (n = 11), after – 31.6 % (n = 6). The decrease occurred in 100 %, the disappearance – in 45 % (n = 11) of cases. The thickness of the extraosseous component before treatment ranged from 4 to 43 mm (Me = 15 mm), after treatment it ranged from 0 to 30 mm (Me = 8 mm). The decrease occurred in the range from 4 to 14 mm (M ± SD = 7 ± 4 mm). In 100 % of cases, a sclerotic rim appeared, the thickness of which after treatment ranged from 1 to 5 mm (Me = 3 mm). In the structure of the tumor, fibrosis occurred in 95 % (n = 18), a decrease in the cystic component occurred in 82 % (n = 9) of cases. Perifocal changes decreased in 100 % of cases. In 100 %, the average tumor density increased. The mean tumor density before treatment ranged from 27 to 65 HU (M ± SD = 42 ± 11 HU), after treatment it ranged from 69 to 500 HU (Me = 150 HU). The increase in density occurred in the range from 41 to 454 HU (Me = 101 HU). All differences are statistically significant (p < 0.05).Conclusions. Evaluation of effectiveness with the definition of quantitative and qualitative indicators is possible according to the data of both CT and MRI; with CT, changes are recorded longer, and more indicators available for quantitative measurement are determined.