TARGET’s Study of Osteosarcoma
About Osteosarcoma
Osteosarcoma (OS) is the most common type of bone cancer in children and adolescents. It is most frequently diagnosed in adolescent patients experiencing periods of rapid growth. As with other childhood cancers being studied by Therapeutically Applicable Research to Generate Effective Treatments (TARGET), improvements in survival outcomes for OS have plateaued despite attempts in refining the standard treatment protocol.
Additionally, patients endure rigorous therapy regimens regardless of whether the disease is localized or metastatic. Thus, targeted therapies have the potential to enhance the survival and quality of life of patients with this disease. Learn more about osteosarcoma and current treatment strategies.
As of September 1, 2019, NCI has removed restrictions limiting investigators from publishing broad results using OS data from the TARGET initiative. OS datasets are available without restrictions on their use in publications or presentations.
TARGET’s Osteosarcoma (OS) Project
TARGET investigators are analyzing tumors from pediatric patients to identify biomarkers that correlate with poor clinical outcome or new therapeutic approaches to treat childhood OS. The tissues used in this study were collected from patients enrolled in Children's Oncology Group (COG) biology studies and clinical trials and through collaborations with The Hospital for Sick Children (SickKids) in Toronto (Ontario, Canada), Chiba Cancer Center (Chiba, Japan), and the Pediatric Oncology Institute (Sao Paolo, Brazil).
The TARGET OS project has produced comprehensive genomic profiles of ~90 clinically annotated patient cases within the discovery dataset. Each fully characterized TARGET OS case includes data from nucleic acid samples extracted from tumor and normal tissues as follows:
- primary tumor sample collected at the time of diagnosis
- normal tissue sample from peripheral blood (case-matched)
Additional cases with partial molecular characterization and/or sequencing data are available to the research community.
Tissues and clinical data used for the TARGET OS project were obtained from patients enrolled on biology studies and clinical trials managed through COG and through a collaboration with SickKids. Patient samples with full characterization were chosen based on the following criteria:
- tumor cellularity of >50% in tumor specimens and tumor necrosis of <50%
- high-quality nucleic acids in amounts adequate to complete comprehensive genomic profiling
The TARGET OS project team used a variety of sequencing approaches to confirm candidate variants identified in the discovery sample cohort as somatic. These verified variants are being made available as open-access data, and some initial results are available in this oncoprint of initial integrated analyses.
An “oncoprint” diagram showing the recurring combinations of mutations found in the 89 osteosarcoma samples characterized by TARGET.
Some sequence mutations identified in the discovery cohort, along with some previously published variants, are being further analyzed in a validation cohort made up of more than 180 additional cases. This validation effort is being performed in an unbiased cohort that was randomly selected based on tissue availability from patients enrolled on COG protocols or studies run through additional collaborative efforts (including international cohorts from Canada, Japan, and Brazil), which allows for determination of the frequency of these changes across a broader spectrum of OS subtypes.