This test is indicated in nearly all breast cancers and is appropriate in both lumpectomy and mastectomy patients. The procedure starts on the day of your surgery with a visit to the nuclear medicine or radiology department where an injection of radioactive tracer called technetium sulphur colloid is performed by a physician.
At the time of surgery, after you are asleep, a vital blue dye may be injected around the tumor bed. These two traces act as a road map for your surgeon to find those first lymph nodes in the chain. When the sentinel lymph node is found, a frozen section (quick diagnosis) is performed. Once the sentinel lymph node is identified, your surgeon will feel for other lymph nodes in your armpit that may have tumor in them. Lymph nodes filled completely with cancer cells may not have the ability to pick up the radioactive tracer and blue dye, therefore this is an important part of the process.
If the frozen section reveals spread of cancer cells to the lymph nodes, additional lymph nodes may be removed at the time. If the frozen section is negative for spread of the cancer, then no further lymph node surgery is performed at that time. At your postoperative visit, you will discuss your final pathology, which will include the results of your margins of tumor resection and the final staining of the lymph nodes for tiny areas of tumor spread.