Physicians are now testing the use of fluorescent dye to know during surgery which cells are cancerous or not. If the light is turned off in the surgery room, body parts will shine which indicates where cancer cells exist.

Often, during surgery, there is a chance that the surgeon left behind cancer cells or some lurked behind undetected. It is because it is difficult for physicians to distinguish between the cancerous cell and the healthy cell, NBC reported.

Bionic vision

By using dyes during surgery, the cancer cells will light up which is a signal for the surgeon to cut it off. Dr. Sunil Singhal, at the University of Pennsylvania, compared the dyes to doctors having bionic vision.

There are two dyes in late-stage trials that are with the US Food and Drug Administration for approval. One of the dyes was developed by Johnson & Johnson which invested $40 million.

The inspiration behind the fluorescent came to Singhal 10 years ago when he was thinking about a student who died after her lung cancer returned. Singhal thought he had removed all of the cancerous cells from her lungs.

While gazing at fluorescent decals, he thought to himself that it would be cool if doctors can make cells light up so people would no longer die from unseen tumors. He used a dye called ICG on Ryan Cicozzi, a 45-year-old highway worker from Deptford, New Jersey. Singhal found hidden cancer near the heart of the patient and in a lung.

ICG has long been used for different medical purposes. When big doses of ICG were given by IV one day before the surgery, it collected in cancer cells and lit up when exposed to near-infrared light. Singhal called it TumorGlow and he has been testing it for lung, brain, and other tumor types.

At On Target Laboratories, based in Purdue research park in Indiana, Singhal is testing a dye which binds to a protein more common in cancer cells. A late-stage study is being conducted for ovarian cancer and a mid-stage one for lung cancer.

Singhal said that after they started using the dye, they soon noticed smaller nodules they did not see before. Because of the dye, they can alter the incisions based on the location and type of tumor and begin making an incision directly over the tumor. Before the dye, they had to make some generic decisions, Singhal said, Tech Times reported.

Rate of success

According to one trial, the dye highlighted 56 of 59 lung cancers seen on scans before the operation. Nine more that were not visible ahead of time were spotted.

The dye is expected to benefit about 80,000 Americans who have surgery for suspicious lung spots every year. It can show that cancer is confined to a small node, and then the surgeon can remove a wedge instead of a whole lobe and preserve more breathing capacity, Marty Low, the chief of On Target, said.

Although there is no price set for the dye, since it is cheap to manufacture, the cost should fit within the rates that hospitals negotiate with insurers for surgeries.

Dr. Len Lichtenfeld, from the American Cancer Society, said that dyes may hold promise for breast cancer patients. He estimated that up to one-third of women had a lump removed near a second operation because margins were not clear. It turned out later than an edge of the removed tissue was later found to harbor cancer.

Dr. Barbara Smith, a breast surgeon at Massachusetts General Hospital, leads a late-stage study of Lumicell's system in 400 breast cancer patients. All of the cells were cancerous, as verified by tissue tests later, in an earlier study of 60 women.

Smith noted that MarginProbe, a device now sold in the market, uses different technology to study the surface of the tissue that has been taken out. But it cannot pinpoint in the breast where the residual disease lurks.

Other types of cancer

The Fred Hutchison Cancer Research Center and Seattle Children's Hospital patented Tumor Paint, a combo product that has a molecule which binds to cancer and a dye to make it glow. Blaze Bioscience is testing Tumor Paint, Dr. Jim Olson, the co-founder of the research center, said.

He said that with Tumor Paint, surgeons can see it down to a few dozen cells or a few hundred cells. Using the combo product, early-stage studies have been held for skin, brain, and breast cancers in adults and brain tumors in children, the Associated Press reported.

Meanwhile, Avelas Biosciences is working on a dye attached to a molecule that can carry it into tumor cells. There are now early studies being conducted on breast cancer patients. Avelas plans to do more studies for colon, head and neck, ovarian, and other types of cancer.

Carmine Stengone, the president of Avelas, noted that cancer drugs have had a lot of attention, while ways to improve surgery had far less. It was just a very overlooked area even if there was a high medical need, she said.

[researchpaper 리서치페이퍼= Vittorio Hernandez 기자]