Multicenter real-world experience of the clinical efficacy and tolerance of pazopanib in high-risk pediatric solid tumors (PazoPed).

Pazopanib, a receptor tyrosine kinase inhibitor, exhibits anti-tumor activity in adult bone and soft-tissue sarcomas (STS), but has not yet been approved for pediatric tumors. The primary objective was to evaluate pazopanib efficacy when used alone or in combination with topotecan. This real-world multicenter retrospective study included patients with solid tumors, aged 25 years or less at the time of initial diagnosis, treated with pazopanib outside of a clinical trial. Nineteen patients were eligible for efficacy analysis: 14 bone tumors and 5 STS. At pazopanib initiation, the median age was 16.9 years, 18 patients had metastatic disease with a median of 2 prior therapeutic lines. With 6.2 months of median follow-up, no objective response was observed, but 10 patients (52.6%) had stable disease at 8 weeks and the 6-month disease control rate was 26.3%. The median progression free (PFS) and overall survival (OS) were 3.0 months and 6.2 months, respectively. Multivariate analysis showed an inverse relationship between the number of prior treatment lines and PFS and OS (hazard ratio = 1.73 (p = 0.04) and 1.76 (p = 0.03), respectively). Our study showed a potential tumor control activity of pazopanib in pediatric bone and soft tissue sarcomas. Further studies are warranted to determine the optimal timing and condition for pazopanib introduction to maximize the effect.

Right atrial catheter "ghost" removal by cardiac surgery: A pediatric case series report.

Fibrin sheath formation around long-term indwelling central venous catheters is common and usually benign. Fibrin sheath can persist after catheter removal and rarely leads to complications. This is a report of three pediatric oncology patients that required cardiac surgery for cardiac embolization of a "ghost" catheter several years after catheter removal. One case required tricuspid valve replacement for complete tricuspid valve destruction and two had erosion through the atrial wall. The severity of these rare complications mandates follow-up of "ghost" catheters in pediatric oncology patients.

Very Early Diagnosis and Management of Congenital Erythropoietic Porphyria.

Congenital erythropoietic porphyria (CEP), a rare form of porphyria, is caused by a defect in the heme biosynthesis pathway of the enzyme uroporphyrinogen III synthase (UROS). Uroporphyrinogen III synthase deficiency leads to an accumulation of nonphysiological porphyrins in bone marrow, red blood cells, skin, bones, teeth, and spleen. Consequently, the exposure to sunlight causes severe photosensitivity, long-term intravascular hemolysis, and eventually, irreversible mutilating deformities. Several supportive therapies such as strict sun avoidance, physical sunblocks, red blood cells transfusions, hydroxyurea, and splenectomy are commonly used in the management of CEP. Currently, the only available curative treatment of CEP is hematopoietic stem cell transplantation (HSCT). In this article, we present a young girl in which precocious genetic testing enabled early diagnosis and allowed curative treatment with HSCT for CEP at the age of 3 months of age, that is, the youngest reported case thus far.

Bisphosphonates in Langerhans Cell Histiocytosis: An International Retrospective Case Series.

BACKGROUND: Bone is the most common organ of involvement in patients with Langerhans cell histiocytosis (LCH), which is often painful and associated with significant morbidity from pathological fractures. Current first-line treatments include chemotherapy and steroids that are effective but often associated with adverse effects, whereas the disease may reactivate despite an initial response to first-line agents. Bisphosphonates are osteoclast inhibitors that have shown to be helpful in treating bone lesions of LCH. To date, there are no large international studies to describe their role in treating bone lesions of LCH. METHOD: We conducted a multicenter retrospective review of 13 patients with histologically proven LCH, who had received bisphosphonates either at diagnosis or at disease reactivation. RESULTS: Ten patients (77%) had a single system bone disease, and 3 (23%) had bone lesions as part of multisystem disease. Median follow-up time post-bisphosphonate therapy was 4.6 years (range, 0.8 to 8.2 years). Treatment with bisphosphonates was associated with significant pain relief in almost all patients. Twelve (92%) achieved resolution of active bone lesions, and 10 out of them had no active disease for a median of 3.5 years (range, 0.8 to 5 years). One patient did not respond. No major adverse effects were reported in this series. CONCLUSION: Bisphosphonates are well-tolerated drugs that can significantly improve bone pain and induce remission in active bone LCH. Future prospective studies evaluating the role of bisphosphonates in LCH are warranted.