Radiolabeled Octreotide in Treating Children With Advanced or Refractory Solid Tumors

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed malignant neoplasm * Not amenable to standard therapy or has failed existing first- and second-line therapies * Tumor positive for somatostatin receptors by OctreoScan within the past 4 weeks * At least 1 measurable lesion * Lesions that have been previously irradiated must demonstrate progression since radiation * At least 1 measurable somatostatin receptor-positive lesion that has not been irradiated within the past 4 weeks AND has not had full craniospinal radiation within the past 3 months * Bone marrow with at least 40% cellularity OR at least 20% cellularity with one million CD34+ stem cells/kg stored * No diffuse bone marrow involvement by OctreoScan scintigraphy PATIENT CHARACTERISTICS: Age * 2 to 25 Performance status * COG 0-2 OR * Karnofsky 60-100% OR * Lansky 60-100% Life expectancy * 2-12 months Hematopoietic * See Disease Characteristics * Absolute neutrophil count at least 1,000/mm\^3 * Platelet count at least 100,000/mm\^3 Hepatic * Bilirubin less than 1.5 times normal * AST and ALT less than 2.5 times upper limit of normal Renal * Creatinine no greater than 1 mg/dL (children less than 5 years of age) * Creatinine less than 1.2 mg/dL (children 5 to 10 years of age) * Creatinine less than 1.7 mg/dL (children over 10 years of age) AND * Glomerular filtration rate at least 80 mL/min/m\^2 Cardiovascular * Shortening fraction at least 28% by echocardiogram * Ejection fracti…