Osteosarcoma can rarely occur as a subsequent malignant neoplasm after cancer therapy. Children who underwent treatment for cancer and received an allogeneic hematopoietic cell transplant are at a higher risk to develop secondary malignancies. Radiation is also a known risk factor, but estimating the quantitative risk is difficult due to the rarity of the condition and long latency period between primary and secondary cancer. In this report, we present 3 patients diagnosed with leukemia as young children who received hematopoietic cell transplants with total body irradiation as part of the conditioning regimen, and later went on to develop secondary osteosarcoma.

Donor cell leukemia is a rare complication following hematopoietic stem cell transplant (HSCT). There are currently few reports in children and only rare, reported cases of donor-derived myelodysplastic syndrome/acute myeloid leukemia in patients with an underlying germline GATA2 mutation. Most reported cases are myeloid in origin and occur following related HSCT. We present a 3-year-old female who developed a donor-derived B-cell acute lymphoblastic leukemia 2 years post unrelated HSCT for GATA2 germline mutation.

Asparaginase, a critical component of current pediatric acute leukemia treatment protocols, is associated with a number of serious side effects, one of which is pancreatitis. Pancreatitis can result in significant morbidity and mortality from necrosis, pseudocyst formation, hemorrhage, systemic inflammation, intestinal perforation, and sepsis. Another rare complication of pancreatitis is posterior reversible encephalopathy syndrome, likely mediated by systemic inflammation secondary to pancreatic autodigestion and proinflammatory cytokine-mediated vascular endothelial damage. Here, we review this association in the literature and report 2 pediatric patients with leukemia who developed posterior reversible encephalopathy syndrome in the setting of asparaginase-associated pancreatitis.