Physicians at the Dartmouth-Hitchcock Norris Cotton Cancer Center in New Hampshire have collaborated with engineers from Dartmouth's Thayer School of Engineering to develop a new imaging-based approach to breast-conserving surgery that simplifies the procedure for women whose breast cancer is too small to be felt.
By combining magnetic resonance imaging (MRI) before surgery with optical scanning during surgery, they are able to accurately locate small breast cancer tumors for removal. The researchers’ findings, "Supine Breast MRI and 3D Optical Scanning: A Novel Approach to Improve Tumor Localization for Breast Conserving Surgery," were recently published in Annals of Surgical Oncology.
"We have developed a technique that gives the surgeon, at the time of surgery, a 3-D picture of where the cancer is in the breast using MRI," Richard Barth, M.D., section chief, general surgery, associate professor of surgery, Geisel School of Medicine, Dartmouth said in a statement."This is the first time that optical scanning and MRI have been combined to localize breast cancer."
Currently, a wire is inserted into the breast before surgery to mark these small tumors. This technique requires a separate procedure, which can be uncomfortable for the patient and is not very accurate—cancer cells are left behind about 30 to 40 percent of the time, and additional surgery is needed to remove remaining cancer.
Barth says that this new method of locating breast tumors uses a pre-operative MRI as a map of the tumor and an optical scan to identify the tumor's size, shape, and location. Combined, the two create an interactive 3-D image on a computer screen. Conceptually it is similar to a car's GPS. The uploaded maps would be the MRI, and the optical scan provides the "you are here" arrow for the surgeon. This more accurate picture of the tumor location and its edges allows for a more precise surgical excision.
Barth will soon be initiating a randomized prospective study of patients with non-palpable breast cancer to test whether the new method of localization with optical scanning and supine MRI results in a lower rate of positive margins than the old wire localization method, according to officials.