DNA, RNA sequencing of 500 patients reveals potential treatment targets, deeper understanding of metastatic cancer.
The average metastatic cancer has more genetic mutations than are seen in early stage tumors, a new study finds. What that means: To make precision medicine a reality in cancer care, you need a real–time, comprehensive approach that looks at the metastatic tumors and sequences to a level of detail beyond most commercial tests.

In one of the largest and most comprehensive efforts to examine the genetic and molecular landscape of advanced cancer, researchers at the University of Michigan Comprehensive Cancer Center sequenced the DNA and RNA of 500 patients with metastatic cancer.

The results were published in the journal Nature.

Three things make this analysis unique:

• Researchers obtained fresh biopsies for most patients, extracting samples from the metastatic tumors, rather than the primary tumor.
• They sequenced both DNA and RNA.
• They compared the cancerous tissue to the patient’s normal DNA.

“This is a more comprehensive approach than most commercially available clinical sequencing programs. Our results suggest value on several levels to this more detailed approach,” says senior study author Arul Chinnaiyan, MD, PhD, director of the Michigan Center for Translational Pathology.

The data reflects the first 500 patients with solid tumors to enroll in the Michigan Oncology Sequencing Program, a research protocol that began in 2010, sequencing the DNA and RNA of metastatic cancers and normal tissue to identify alterations that could help drive treatment. The program includes a precision medicine tumor board in which experts discuss each case. Mi–ONCOSEQ was among the first comprehensive clinical sequencing programs offered for cancer patients.

The patients represented in the paper spanned more than 30 types of cancer, with metastases in 22 different organs. It includes only adults with solid tumors, although Mi–ONCOSEQ is available to patients with blood cancers and to children.