Musculoskeletal complications following total body irradiation in hematopoietic stem cell transplant patients.

Total body irradiation (TBI) is commonly used in conditioning regimens for allogeneic hematopoietic stem cell transplantation (HSCT) to treat benign and malignant disease. Though life-saving, these therapies place patients at risk for important side effects, including musculoskeletal complications such as short stature, osteonecrosis, slipped capital femoral epiphysis, and the development of benign and malignant bone tumors. With an increasing number of HSCT survivors, there is a growing need for awareness of the musculoskeletal complications of HSCT and TBI.

Diagnosis of Beckwith-Wiedemann syndrome in children presenting with Wilms tumor.

Beckwith-Wiedemann syndrome (BWS) is a genetic syndrome associated with overgrowth and cancer predisposition, including predisposition to Wilms tumor (WT). Patients with BWS and BWS spectrum are screened from birth to age 7 years for BWS-associated cancers. However, in some cases a BWS-associated cancer may be the first recognized manifestation of the syndrome. We describe 12 patients diagnosed with BWS after presenting with a WT. We discuss the features of BWS in these patients and hypothesize that earlier detection of BWS by attention to its subtler manifestations could lead to earlier detection of children at risk for associated malignancies.

Management of Refractory Pediatric Kaposiform Hemangioendothelioma With Sirolimus and Aspirin.

Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor characterized by aggressive local invasion and a syndrome of platelet trapping known as Kasabach-Merritt phenomenon that, through deposition of platelet derived growth factors, may perpetuate the growth of the tumor. Although many cases of KHE are successfully treated with local control or low-intensity chemotherapy, some cases are often refractory even to aggressive treatment. Herein, we describe a patient with a refractory, recurrent KHE despite multiple attempts at local control and intensive chemotherapy, that ultimately was successfully treated with rationally designed and low-intensity combination therapy of sirolimus and aspirin.

Ectopic production of ß-hCG by osteosarcoma: a case report and review of the literature.

Ectopic production of ß-human chorionic gonadotropin (ß-hCG) by nontrophoblastic tumors has been reported but mostly in carcinomas. We report a case of an adolescent female patient with a epithelioid osteosarcoma that was discovered to secrete ß-hCG after routine pregnancy testing. Immunohistochemical staining of her primary tumor biopsy demonstrated immunoreactivity for ß-hCG. Levels of serum ß-hCG were monitored throughout her therapy and demonstrated normalization with effective systemic therapy and local control. She remains disease free 6 months off therapy, with undetectable hormone levels. A review of the available literature on ß-hCG production by sarcomas is also presented.

Ewing's sarcoma.

Progress in the treatment of Ewing's sarcoma, the second most common bone tumour in children and adolescents, has improved survival from about 10% in the period before chemotherapy was introduced to about 75% today for patients with localised tumours. However, patients with metastases still fare badly, and the therapy carries short-term and long-term toxicities. Multidisciplinary care is indispensable for these patients. Molecular techniques and new imaging modalities are affecting the diagnosis and classification of patients with Ewing's sarcoma. Cooperative group studies have led to chemotherapy regimens using the same drugs (vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide), although the exact regimens differ in Europe and North America. The EWS-ETS family of gene fusions and their downstream effects in Ewing's sarcomas provide opportunities for new approaches to treatment. These include the inhibition of the fusion gene or its protein product, and pathways related to IGF1 and mTOR. Inhibition of tyrosine kinases, exploitation of non-apoptotic cell death, and interference with angiogenesis are promising new approaches. With many new approaches and relatively few patients, it will be challenging to integrate new and established treatments through clinical trials.

Serial transcriptome analysis and cross-species integration identifies centromere-associated protein E as a novel neuroblastoma target.

Cancer genomic studies that rely on analysis of biopsies from primary tumors may not fully identify the molecular events associated with tumor progression. We hypothesized that characterizing the transcriptome during tumor progression in the TH-MYCN transgenic model would identify oncogenic drivers that would be targetable therapeutically. We quantified expression of 32,381 murine genes in nine hyperplastic ganglia harvested at three time points and four tumor cohorts of progressively larger size in mice homozygous for the TH-MYCN transgene. We found 93 genes that showed a linearly increasing or decreasing pattern of expression from the preneoplastic ganglia to end stage tumors. Cross-species integration identified 24 genes that were highly expressed in human MYCN-amplified neuroblastomas. The genes prioritized were not exclusively driven by increasing Myc transactivation or proliferative rate. We prioritized three targets [centromere-associated protein E (Cenpe), Gpr49, and inosine monophosphate dehydrogenase type II] with previously determined roles in cancer. Using siRNA knockdown in human neuroblastoma cell lines, we further prioritized CENPE due to inhibition of cellular proliferation. Targeting CENPE with the small molecular inhibitor GSK923295 showed inhibition of in vitro proliferation of 19 neuroblastoma cell lines (median IC(50), 41 nmol/L; range, 27-266 nmol/L) and delayed tumor growth in three xenograft models (P values ranged from P < 0.0001 to P = 0.018). We provide preclinical validation that serial transcriptome analysis of a transgenic mouse model followed by cross-species integration is a useful method to identify therapeutic targets and identify CENPE as a novel therapeutic candidate in neuroblastoma.

Use of rituximab in conjunction with immunosuppressive chemotherapy as a novel therapy for Epstein Barr virus-associated hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis is a rare, life-threatening complication of Epstein Barr virus (EBV) infection. Current treatments are directed at reducing virus-induced immune dysregulation. Addition of agents that eliminate EBV-infected B cells may improve therapeutic efficacy. On the basis of the observations that the anti-CD-20 monoclonal antibody rituximab reduces disease burden in individuals with EBV-associated lymphoproliferative disorders, we treated a patient with severe EBV-hemophagocytic lymphohistiocytosis using a combination of rituximab and chemotherapy. This patient demonstrated a rapid clinical response and an 18-fold reduction in EBV viral load within 24 hours of receiving rituximab. He remains free of disease 8 months after completing treatment.