Isolated diaphragmatic metastasis from periosteal osteosarcoma of the humerus: A case report

Abstract

Background: Isolated diaphragmatic metastasis is rarely associated with periosteal osteosarcoma. Case presentation: A 24-year-old female patient was found to have periosteal osteosarcoma of the right humerus 11 years ago. Computed tomography showed a mass in her left chest in 2018, and thoracotomy was performed to remove the tumour. The tumour showed the same characteristics as the original periosteal osteosarcoma. Genetic analysis of the tumour sample showed a TP53 point mutation and CCNE1 gene copy number variants. Conclusions: We believe this is the first case report of haematogenous metastasis to the diaphragm of periosteal osteosarcoma, and an investigation of the genetic factors may help to unravel the underlying cause of periosteal osteosarcoma.