Osteosarcoma is the most common form of bone cancer in children and adolescents, occurring most often between the ages of 10 and 19. Unfortunately, the disease often returns after treatment. In that case, treatment with chemotherapy (ifosfamide and etoposide; IE) usually follows.
The purpose of this study was to see if adding lenvatinib to IE chemotherapy improves outcomes. Lenvatinib is a so-called tyrosine kinase inhibitor (TKI). Evidence suggests that a combination of a TKI with chemotherapy could work well in recurrent osteosarcoma.
International study
Between March 2020 and November 2021, 81 children and young adults (2-25 years old) entered the study. All had relapsed or refractory osteosarcoma, that is, the disease had returned or failed to respond to previous treatment. Half of the study participants received the standard treatment with chemotherapy (IE); the other half received lenvatinib in addition to chemotherapy.
The study was conducted in 18 different countries in Europe, Asia and the Pacific, and North America. From the Princess Máxima Center, two children participated.
Small difference
In the group that received lenvatinib and chemotherapy, the tumor took slightly longer to start growing again: an average of 6.5 months compared to an average of 5.5 months in those who received chemotherapy alone. But this small difference was not statistically significant, so the possibility of coincidence cannot be ruled out. Children who had not previously been treated with ifosfamide, or who had received only one previous treatment, appeared to benefit from lenvatinib slightly more. However, these subgroups were too small for any conclusions to be drawn.
In both groups, most study participants experienced side effects, such as decreased thyroid function, anemia and nausea. These side effects were the same as was previously seen with IE chemotherapy and lenvatinib.
Valuable information
This is one of the few international studies in children and young adults with recurrent osteosarcoma. International cooperation is important to allow for sufficient numbers of children to participate in a study. The study provided valuable information for clinical practice and future study design. Future research should look at even larger groups of patients to further determine the role of TKIs in the treatment of relapsed osteosarcoma.