Postoperative Outcomes with and without Neoadjuvant Denosumab in Grade-III Giant Cell Tumor of the Proximal Femur: A Comparative Retrospective Study.

OBJECTIVE

To retrospectively compare the impact of using neoadjuvant denosumab for Campanacci grade-III giant cell tumor (GCT) of the proximal femur involving the hip joint.

METHODS

We retrospectively reviewed 18 cases of Campanacci grade-III GCT of the proximal femur receiving surgery between January 2014 and December 2019 from our hospital. One group of 10 patients received weekly neoadjuvant denosumab 120 mg for 4 weeks, while the other group of 8 patients did not receive denosumab before surgery. Two patients were subjected to intralesional curettage while the others received resection and hip arthroplasty. Comparisons were made using unpaired -test and Fisher's exact test. Functional outcomes were assessed by revised Musculoskeletal Tumor Society (MSTS) score and Harris Hip Score (HHS) at 6 weeks, 6 months, and 12 months of follow-up, as well as incidence of recurrence.

RESULTS

The comparison of the mean MSTS scores of the denosumab and non-denosumab groups was as follows: 24.0 ± 6.5 versus 20.0 ± 6.0 (  = 0.04) at 6 weeks respectively; 26.0 ± 5.0 versus 23.0 ± 0.67 (  = 0.04) at 6 months respectively; and 28.8 ± 1.7 versus 29.5 ± 0.33 (  = 0.35) at 12 months respectively. The comparison of HHSs between the denosumab and non-denosumab groups was as follows: 61.02 ± 7.36 versus 48.52 ± 3.97 (  = 0.03) at 6 weeks respectively; 81.1 ± 2.97 versus 79.15 ± 3.24 (  = 0.82) at 6 months respectively; and 89.84 ± 3.75 versus 90.05 ± 3.00 (  = 0.38) at 12 months respectively. There was no recurrence.

CONCLUSION

Denosumab was clinically effective in improving the short-term functional outcomes, but long-term functional outcomes remained similar between the groups. We did not find an increased recurrence rate in the denosumab group.