Nutritional status of children and young adults with Ewing sarcoma or osteosarcoma at diagnosis and during multimodality therapy.

OBJECTIVE: Objective of our study was to evaluate the nutritional status and growth of children and adolescents with common malignancies of the musculoskeletal system at diagnosis, and undergoing multimodality therapy. METHODS: A retrospective analysis of data from 2001 to 2009 was conducted. Hospital charts were used as a source of clinical data. Primary endpoint of the analyses was to identify variations in anthropometric parameters at diagnosis and during the first 2 years of follow-up in children and adolescents with osteosarcoma or Ewing sarcoma. Factors contributing to disorders of growth in this population were sought. RESULTS: A total of 139 children were registered, 62 with Ewing sarcoma and 77 with osteosarcoma. At diagnosis 72.7% of all patients were classified as adequately nourished (BMI 5th to <85th percentiles). During treatment all anthropometric parameters were markedly reduced (P < 0.001) in both groups with extreme changes in body weight from -30% to +44%. This was pronounced in children affected by osteosarcoma (P < 0.05). During follow-up, recovery of body weight was noted in both groups. Height Z-scores remained low (P < 0.001) in comparison to the general population. After the observation period 43.4% of the children with osteosarcoma and 25.5% of the patients with Ewing sarcoma demonstrated an altered body mass. CONCLUSIONS: Pediatric patients with Ewing sarcoma or osteosarcoma are at an increased risk for developing malnutrition, in the form of either over- or underweight during multimodality therapy. Early recognition of abnormal body mass is required to prevent and to treat long-term comorbidities caused by malnutrition.

The tyrosine kinase c-Abl promotes proliferation and is expressed in atypical teratoid and malignant rhabdoid tumors.

BACKGROUND: Atypical teratoid/rhaboid tumors (AT/RTs) and extracranial malignant rhabdoid tumors are highly malignant neoplasms with a dismal prognosis. These tumors predominantly affect infants and targeted, adjuvant treatment approaches would be highly desirable. METHODS: In the current study, the authors investigated the expression and functional role of tyrosine kinases in 2 malignant rhabdoid tumor cell lines (A204 and G401) and in a series of 5 AT/RTs and 18 malignant rhabdoid tumors (13 rhabdoid tumors of the kidney and 5 extrarenal rhabdoid tumors). RESULTS: Both cell lines consistently expressed the tyrosine kinase c-Abl, which promoted proliferation as assessed by small interfering RNA knockdown. Blockage of c-Abl using the tyrosine kinase inhibitor imatinib resulted in reduced cellular growth in both cell lines. Furthermore, c-Abl was expressed in all rhabdoid tumors, whereas expression of platelet-derived growth factor receptor subtypes alpha and beta was infrequent and c-Kit expression was absent. CONCLUSIONS: The current data pointed toward a role for c-Abl in the biology of malignant rhabdoid tumors and provided a rationale for the investigation of tyrosine kinase inhibitors that target c-Abl for the treatment of these aggressive tumors.