Genome sequencing of tumors biopsied from women with invasive breast cancer

December 23, 2015

Similar types of genome-sequencing studies are being considered for other types of malignancies, such as colorectal cancer and potentially lung cancer, Dr. Mardis said.

"Genome sequencing is a rapidly changing field. Only about three years ago, it took us eight months to sequence through a whole cancer genome in a leukemia patient. In the next couple of months, we will be doing tumor and normal genomic analysis in about a week. So you can get an idea of the rate of accumulation of data and the dramatic upsweep in terms of our capacity to perform whole genome sequencing in just the last couple of years," Dr. Mardis said.

Sequencing an entire genome tends to be costly and time-consuming. However, spot testing for the presence of a small number of genes can be performed quickly and cost-effectively, she said. "Sequence typing of specific genes is very doable in the current laboratory testing paradigm using a fairly small amount of DNA from a core biopsy. In the next few months, new technologies are coming online that will allow a genetic assay to be completed in less than a day. So you would have very fast turnaround, and the cost of the assay would be fairly low. Only time will tell whether we have to use the entire genome to make predictions about a patient's aromatase inhibitor profile or whether we can get away with a focused, gene-by-gene approach," she said.

Source American College of Surgeons Oncology Group (ACOSOG)