Experimental 'iKnife' Tells Surgeon Whether Tissue Is Cancerous
WEDNESDAY July 17, 2013 -- An experimental surgical "knife" can accurately identify cancerous tissue as a surgeon cuts through it, creating the potential for shorter cancer surgeries that remove all traces of tumor, according to a study co-written by the device's developers.
The "iKnife" uses electricity to cauterize surgical incisions as they are made, and then samples the resulting smoke to determine whether the tissue being cut is healthy or cancerous.
The iKnife accurately identified cancerous and healthy tissue 97 percent of the time in recent human trials, according to the study published July 17 in the journal Science Translational Medicine.
However, one cancer expert said it's too soon to tell if the device will make a difference in real-world practice and whether it would be worth the hefty cost.
The new technology analyzes the smoke from cauterized incisions and compares the results to a database of nearly 3,000 tissue-specific "signatures."
It can be difficult for cancer surgeons to tell if they've completely removed a tumor. They currently must send tissue samples to a pathologist and then wait 20 to 30 minutes -- with the patient still under anesthesia -- to see if they have successfully removed all cancer cells, according to background information in the study.
By comparison, diagnosis using the iKnife takes up to three seconds, said study co-author Zoltan Takats, a researcher with computational and systems medicine in the department of surgery and cancer at Imperial College London.
"We believe using this technology, since there is no waiting time, can significantly reduce the amount of time the patient spends in the operating theater," Takats said. "We also can hopefully decrease the local tumor recurrence rate, which in cases like breast cancer can be as high as 30 percent."
Researchers developed and tested the technology with funding from the European Research Council and the National Institute for Health Research in Great Britain, Takats said. They have since formed a company, MediMass, funded by venture capital to further develop and market the iKnife.
The trials reported in the new study involved 81 patients undergoing cancer surgery at three Hungarian hospitals. The iKnife's readings were compared to post-surgery analysis of the same tissue samples to determine the device's accuracy.
Capital equipment costs for the iKnife will be more than $380,000 per unit, said Jeremy Nicholson, a co-researcher of Takats' at Imperial College London.
However, the researchers contend that the iKnife ultimately could save money by allowing hospitals to downsize their pathology departments and by reducing staff time spent in surgery.
"The cost per patient will probably be quite small in comparison with the overall patient journey, and if the patient treatment is better with lower cancer recurrence then there is a very large saving to the health service," Nicholson said.
The next step in research will be clinical trials with the iKnife "where we are giving real-time feedback to the surgeon and they can make decisions based on that feedback," Takats said.
Takats estimates the new technology could be approved and available for use within two to three years.
Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society, called the science behind the iKnife "fascinating." But, he added that more research will be needed before it can be considered a sound investment for hospitals.
"The real question everybody's going to ask is can this be translated directly to clinical practice," Lichtenfeld said. "The answer is possibly, but there's a lot of work that has to be done before that happens, and it would have to demonstrate a clear benefit to the patient and the health-care system before it would happen. It's still quite a ways from actually showing up in an operating room at a local hospital."
Lichtenfeld pointed to robotic surgery technology meant to improve results for prostate cancer patients. Many hospitals purchased robots but the expected improvements have not panned out, he said.
"People are only now asking if they make enough of a difference to justify the cost of the robot," he said. "We can't get into that situation again. We need to have scientific research before we have widespread adoption of new technology."
The American Cancer society explains how a cancer diagnosis is made.
Posted: July 2013