A New Technique Aims to Ensure That Surgeons Completely Remove Cancer
Researchers have developed a technique to allow breast-cancer surgeons to determine during an operation whether all cancerous tissue has been removed.
Of the quarter-million women diagnosed with breast cancer every year in the United States, about 180,000 undergo surgery to remove the cancerous tissue while preserving as much healthy breast tissue as possible.
However, there’s no accurate method to tell during surgery whether all of the cancerous tissue has been successfully removed. The gold-standard analysis takes a day or more, much too long for a surgeon to wait before wrapping up an operation. As a result, about a quarter of women who undergo lumpectomies receive word later that they will need a second surgery because a portion of the tumor was left behind.
Now, researchers at Washington University School of Medicine in St. Louis and California Institute of Technology report that they have developed a technology to scan a tumor sample and produce images detailed and accurate enough to be used to check whether a tumor has been completely removed.
Called photoacoustic imaging, the new technology takes less time than standard analysis techniques. But more work is needed before it is fast enough to be used during an operation.
The research was published May 17 in Science Advances.
“This is a proof of concept that we can use photoacoustic imaging on breast tissue and get images that look similar to traditional staining methods without any sort of tissue processing,” Deborah Novack, MD, PhD, an associate professor of medicine, and of pathology and immunology, and a co-senior author on the study, said in a news release from Washington University.
The researchers are working on improvements that they expect will bring the time needed to scan a specimen down to 10 minutes, fast enough to be used during an operation. The current gold-standard method of analysis, which is based on preserving the tissue and then staining it to make the cells easier to see, hasn’t gotten any faster since it was first developed in the mid-20th century.
For solid tumors in most parts of the body, doctors use a technique known as a frozen section to do a quick check of the excised lump during the surgery. They look for a thin rim of normal cells around the tumor. Malignant cells at the margins suggest the surgeon missed some of the tumor, increasing the chances that the disease will recur.
But frozen sections don’t work well on fatty specimens like those from the breast, so the surgeon must finish a breast lumpectomy without knowing for sure how successful it was.
“Right now, we don’t have a good method to assess margins during breast cancer surgeries,” said Rebecca Aft, MD, PhD, a professor of surgery and a co-senior author on the study. Aft, a breast-cancer surgeon, treats patients at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine.