Osteosarcoma after bone marrow transplantation

Area of Science:

• Pediatric Oncology
• Hematology
• Bone Marrow Transplantation

Background:

• Hematopoietic stem cell transplantation (HSCT) is a curative therapy for various hematologic malignancies and genetic disorders.
• Long-term survivors of HSCT are at risk for secondary malignancies.
• Osteosarcoma is a rare bone cancer, and its occurrence post-HSCT requires careful evaluation.

Observation:

• Three pediatric patients developed secondary osteosarcoma in the tibia years after HSCT for acute lymphoblastic leukemia, Diamond-Blackfan anemia, and congenital amegakaryocytic thrombocytopenia.
• A literature review identified 10 cases of post-HSCT osteosarcoma, with 8 patients having received myeloablative total body irradiation.
• The tibia was the primary site in 60% of post-HSCT osteosarcoma cases, differing from the typical femur predilection in de novo osteosarcoma.

Findings:

• The mean interval from HSCT to osteosarcoma diagnosis was 6 years and 4 months, with a mean age of 14 years and 5 months at diagnosis.
• All three presented cases and at least seven of the reviewed cases are alive and disease-free after treatment with chemotherapy and surgery.
• Total body irradiation prior to HSCT appears to be a significant risk factor for developing secondary osteosarcoma.

Implications:

• Osteosarcoma should be included in the long-term surveillance protocols for patients who have undergone HSCT.
• Awareness of this potential complication can lead to earlier diagnosis and improved outcomes for HSCT survivors.
• Further research is warranted to elucidate the specific mechanisms linking HSCT, particularly TBI, to osteosarcoma development.