Effective treatment of anlotinib in giant delayed pulmonary metastasis of osteosarcoma: a case report and literature review

: Tumor relapse and pulmonary metastasis, especially unresectable lesions, are the major cause of poor prognosis patients with osteosarcoma. Anlotinib, a novel small-molecule tyrosine kinase inhibitor (TKI), has been proved to have desirable anti-tumor effects via blocking VEGFR2 PDGFRβ phosphorylation in several tumors, including non-small cell lung cancer soft tissue sarcoma. In this study, we presented case giant delayed metastasis osteosarcoma which was effectively treated by anlotinib. CT scan patient showed neoplasm size 1,366 cm3 left lung, clinically diagnosed as Due refusing chemotherapy not eligible for surgery neoplasm, anlotinib recommended. As result, tumor volume decreased more than 82% during 24-week administration, from 247 cm3. Unfortunately, disease progression observed at 27-week. Although argon-helium cryoablation (AHC) performed followed apatinib dead 16 weeks after progression. The progression-free survival (PFS) overall since administration 27 43 weeks, respectively. toxicity included hypertension, fatigue hand-foot skin syndrome grade 1–2, were controllable well tolerated. Meanwhile, immunohistochemical staining that expression significantly whole exon sequencing revealed c-MYC duplicated, potentially associated resistance. Anlotinib had promising efficiency treatment metastatic However, potential mechanism resistance subsequent therapy still challengeable needed further investigation.