Lymphoseek injection, manufactured by Navidea Biopharmaceuticals, was first approved in March 2013 for lymphatic mapping procedures of patients diagnosed with breast cancer or melanoma. Doctors inject it to patients to trace the lymph nodes that drain the primary tumor. Tracing the lymph nodes could help doctors decide whether to perform a surgery to remove the tumor or not.

"For some patients with head and neck cancer, removal and pathological examination of lymph nodes draining a primary tumor is an important diagnostic evaluation," said Libero Marzella, M.D., Ph.D., director of the Division of Medical Imaging Products in the FDA's Center for Drug Evaluation and Research, in a news release. "To use Lymphoseek, doctors inject the drug into the tumor area and later, using a handheld radiation detector, find the sentinel lymph nodes that have taken up Lymphoseek's radioactivity."

The researchers tested Lymphoseek on 85 patients with head and neck cancer. The participants were divided into groups: the first group underwent surgical removal of lymph nodes as they were identified malignant by Lymphoseek, the other underwent the same procedure as identified by current tumor location and surgical practice. Both removed tumors were subjected to pathological examination and both showed malignant, thus proving the accuracy of Lymphoseek.

According to the National Cancer Institute, about three percent of all cancers in the United States in the head and neck are caused by alcohol and tobacco use. The current diagnosis procedures used by oncologists include examination under anaesthesia, x-rays and other imaging procedures, and laboratory tests. Lymphoseek will be the latest addition to the procedures that could be performed to stage or identify the extent of the disease.