To further explore some more aggressive subtypes in pediatric cancer already under study in OCG, CGCI is partnering with TARGET initiative to support extensive sequencing analysis of three hard to treat childhood cancers: refractory to treatment cases of acute myeloid leukemia and two rare kidney tumors; clear cell sarcoma of the kidney (CCSK) and rhabdoid tumor. CCSK is a rare, aggressive kidney tumor that usually occurs in children younger than 3 years of age and little is known about the biology of this disease. There are 13 patient cases in the CCSK dataset, each with gene expression, methylation and comprehensive next-generation sequencing to include whole genome sequencing of tumor/normal pairs and mRNA-seq. All cases can be sorted according to data type via the Case Matrix on the TARGET Data Matrix. Please visit the TARGET website, http://ocg.cancer.gov/programs/target, for additional information on this and other TARGET genomics projects. Please see the TARGET Publication Guidelines at the OCG website for updated details on sharing of any TARGET substudy data.