Central nervous system thrombosis in pediatric acute lymphoblastic leukemia in Turkey: A multicenter study.

BACKGROUND: In patients with acute lymphoblastic leukemia (ALL), the risk of thromboembolism increases due to hemostatic changes secondary to the primary disease and due to treatment-related factors. In this multicenter study, we aimed to research the frequency of central nervous system (CNS) thrombosis occurring during treatment, hereditary and acquired risk factors, clinical and laboratory features of patients with thrombosis, treatment approaches, and thrombosis-related mortality and morbidity rates in pediatric ALL patients. PROCEDURE: Pediatric patients who developed CNS thrombosis during ALL treatment from 2010 to 2021 were analyzed retrospectively in 25 different Pediatric Hematology Oncology centers in Türkiye. The demographic characteristics of the patients, symptoms associated with thrombosis, the stage of the leukemia treatment during thrombosis, the anticoagulant therapy applied for thrombosis, and the final status of the patients recorded through electronic medical records were determined. RESULTS: Data from 70 patients with CNS thrombosis during treatment, out of 3968 pediatric patients with ALL, were reviewed. The incidence of CNS thrombosis was 1.8% (venous: 1.5 %; arterial: 0.03%). Among patients with CNS thrombosis, 47 had the event in the first 2 months. Low molecular weight heparin (LMWH) was the most commonly used treatment with a median of 6 months (min-max: 3-28 months). No treatment-related complications occurred. Chronic thrombosis findings occurred in four patients (6%). In five (7%) patients who developed cerebral vein thrombosis, neurological sequelae (epilepsy and neurological deficit) remained. One patient died related to thrombosis, and the mortality rate was 1.4%. CONCLUSION: Cerebral venous thrombosis and, less frequently, cerebral arterial thrombosis may develop in patients with ALL. The incidence of CNS thrombosis is higher during induction therapy than during other courses of treatment. Therefore, patients receiving induction therapy should be monitored carefully for clinical findings suggestive of CNS thrombosis.

Twenty children with non-Wilms renal tumors from a reference center in Central Anatolia, Turkey

Background/aim: Non-Wilms renal tumors (NWRTs) are rarely encountered in children. The aim of this study is to determine the treatment strategies, prognosis, outcomes, and survival of children with NWRTs at Erciyes University in Kayseri, Turkey. Materials and methods: Medical records of all patients (n = 20) treated for NWRTs over a 23-year period (1995­2018) were reviewed retrospectively. Results: There was male predominance (female/male: 7/13); the median age at diagnosis was 3.2 years old (0.1­13.5 years old). The major histological groups included mesoblastic nephroma (MBN), (n: 5, 25%), malignant rhabdoid tumor (MRT), (n: 5, 25%), renal cell carcinoma, (n: 3, 15%), inflammatory myofibroblastic tumor (n: 2, 10%), multilocular cystic renal tumors (n: 2, 10%), metanephric adenoma (n: 1, 5%), renal neuroblastoma (n: 1, 5%), and bilateral renal Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) (n: 1, 5%). All of the patients with NWRTs had radical nephrectomy except the child with bilateral renal ES/PNET. Six children died because of progressive disease; the mortality rate was 30% (n: 6). Conclusion: We have made the first report of bilateral renal involvement of ES/PNET in the English medical literature. Physicians dealing with pediatric renal masses should be alert to the high mortality rate in children with MRT, MBN, and ES/PNET and they should design substantial management plans for NWRTs.

Cranial metastatic alveolar rhabdomyosarcoma mimicking hematological malignancy in an adolescent boy.

BACKGROUND: Widespread alveolar rhabdomyosarcoma (ARMS) with bone marrow involvement and with an unknown primary tumor, especially presenting with acute tumor lysis syndrome can be easily misdiagnosed as a hematological malignancy. Furthermore, brain metastasis of ARMS is rare seen in children. CASE REPORT: Herein, we report a 14-year-old boy presenting with acute tumor lysis syndrome due to bone marrow invasion of ARMS, who was diagnosed after abdominal paraaortic lymph node biopsy. Despite radiological and nuclear medicine imaging, the primary tumor site could not be found. He was treated with vincristine, topotecan, and cyclophosphamide for 42 weeks. Six months after the completion of treatment, he suffered from severe headache, blurred vision, right hemiplegia, and severe bone pain. Cranial magnetic resonance imaging showed multiple hemorrhagic infarctions. Brain biopsy showed brain metastasis with PAX3-FKHR fusion transcript. CONCLUSION: The clinicians must be vigilant about solely brain metastasis in ARMS without additional metastasis.