SALT LAKE CITYA new study of the genetic makeup, or genome, of Ewing sarcoma, a rare cancer that strikes children, teenagers, and young adults, has produced multiple discoveries: a previously unknown sarcoma subtype, genetic factors related to long-term survival, and identification of a genetic change between the primary and metastatic stages of the disease that could lead to better, more targeted treatment.
Researchers from Huntsman Cancer Institute (HCI) at the University of Utah used a new, advanced technology called molecular inversion probes (MIPs) to analyze DNA changes in the genome of Ewing sarcoma tumors. The report appears today in the online issue of the journal Cancer Genetics.
New Subtype of Ewing Sarcoma
According to the study's principal investigator, Joshua Schiffman, M.D., associate professor of pediatrics at the University of Utah and an HCI investigator, up to 10 percent of the tumor samples revealed that DNA in a specific region of the genome was missing, including a gene called SMARCB1. The same deletion had been described before in another aggressive and deadly sarcoma called a rhabdoid tumor. Pathologists double-checked the diagnosis on these samples and determined that they were not misdiagnosed rhabdoid tumors, but were indeed Ewing sarcoma that also had this rhabdoid characteristic.
"Discovering this new subset of Ewing sarcoma is especially important because the patients with this deletion were among the long-term survivors," said Schiffman. "It opens up questions about the biology of this tumor and whether patients with this type of cancer need different treatment."
Genome Factors Correlate with Long-Term Survival
The researchers also looked at the relationship between the Ewing sarcoma genome and patient outcomes and found factors in eight areas of the genome correlated in varying degrees with long-term survival after diagnosis. They compared the samples
|Contact: Linda Aagard|
University of Utah Health Sciences