PathologyMelanoma-containing lymph nodes were detected in 34 (22.1%) patients; Lymphoseek identified all 45 melanoma-positive lymph nodes found in the 34 patients. Four of these 34 node-positive patients were detected exclusively by Lymphoseek. Blue dye detected 36 of the 45 melanoma-positive lymph nodes, but no melanoma-positive lymph nodes were detected exclusively by VBD. Safety Lymphoseek was well tolerated in the trials, with no serious adverse reactions ascribed to the radiopharmaceutical. About Lymphoseek ® Lymphoseek ® (technetium Tc 99m tilmanocept) Injection is a novel, receptor-targeted, small-molecule radiopharmaceutical used in lymphatic mapping procedures that are performed to help stage breast cancer and melanoma. Lymphoseek is designed to identify the lymph nodes that drain from a primary tumor, which have the highest probability of harboring cancer, in patients with breast cancer or melanoma. Lymphatic mapping is a procedure in which lymph nodes that may contain tumor metastases are identified and biopsied to determine if cancer has spread beyond the primary tumor. Accurate staging of cancer is critical, as it guides therapy decisions and determines patient prognosis and risk of recurrence. According to the American Cancer Society, approximately 229,000 new cases of breast cancer and 76,000 new cases of melanoma are expected to be diagnosed in the United States in 2012. About Lymphatic Mapping Lymphatic mapping is a procedure designed to guide lymph node dissection and biopsy procedures. It consists of Intraoperative Lymphatic Mapping (ILM) often accompanied by lymphoscintigraphy. Lymphoscintigraphy is an imaging procedure routinely performed pre-operatively to provide guidance on the location of lymph nodes to be biopsied. ILM is a surgical procedure in which lymph nodes draining the area around a tumor are identified and biopsied to determine if cancer has spread to the lymph nodes. These nodes, commonly referred to as “Sentinel Lymph Nodes,” are removed and analyzed for the presence of malignant cells. Lymphatic Mapping provides an accurate staging procedure that can help ensure optimal surgical and therapeutic choices, including the avoidance of the morbidity of a complete lymph node dissection for patients in whom the Sentinel Lymph Nodes were found to be free of cancer.