Dye Can See Cancer Clearly

Cancer in the lymph nodes accurately detected with newly approved imaging dye

(RxWiki News) Once cancer is detected, the next steps often involve defining the disease. Doctors do what’s called “staging” to determine the extent of the disease. An important part of staging is to learn if the cancer has started to spread.

A new imaging dye helps doctors see if cancer has spread to the lymph nodes.

This new dye – called Technetium Tc-99m tilmanocept – does a better job of identifying involved lymph nodes than existing dyes.

"Find out the stage of your cancer."

When cancer starts to travel from its original site, the first place it usually goes is the lymph nodes – specifically to the ones closest to the tumor, called sentinel lymph nodes.

Lymph nodes are a complex network of vessels that are part of the immune system. These vessels carry cells that fight off disease. Lymph nodes can also carry cancer cells to other areas of the body.

For staging, the sentinel nodes are removed to see if the cancer is on the move. A blue dye is currently used to indicate the nodes that contain cancer.

Physician scientists at the University of California San Diego (UCSD) School of Medicine developed tilmanocept, which was approved by the US Food and Drug Administration on March 13, as a way to improve the imaging of cancerous lymph nodes.

"The molecule, developed at UC San Diego School of Medicine, offers surgeons a new tool to accurately detect and stage melanoma and breast cancers while in the operating room," said David R. Vera, PhD, inventor of the medication, who is a professor in the UCSD Department of Radiology.

Tilmanocept, also known as Lymphoseek, is a radioactive medication (radiopharmaceutical). The radiation acts like a marker and shows where the cancer is located.

For the study, researchers injected both the standard blue dye and tilmanocept into the tumor area of 148 patients who had both melanoma (skin cancer) and breast cancer.

A handheld radiation detector was used to identify the lymph nodes that had taken in the radiation, indicating the presence of cancer.

Tilmanocept correctly identified 94 percent of the cancers compared to the blue dye which found 76 percent.

"Tilmanocept's ability to identify more cancer containing nodes will lead to better post-operative care for patients, especially those patients who had more than one positive sentinel node,” said lead investigator, Lead investigator, Anne Wallace, MD, professor of surgery at UCSD School of Medicine, chief of plastic surgery at UCSD Health System and director of the Breast Care Unit at UCSD Moores Cancer Center.

"Given these results, this agent is safe and provides a modern radiopharmaceutical for future advances in sentinel lymph node mapping," the authors wrote.

Results of the Phase III clinical trial were published in the March issue of Annals of Surgical Oncology. The study was supported by Navidea Biopharmaceuticals, Inc., the manufacturer of Lymphoseek. Dr. Vera is the inventor of the medication. No other authors disclosed conflicts of interest.

Review Date: 
April 1, 2013