New tool could aid breast cancer surgery
ADELAIDE, Australia: Australian researchers have developed an optical fibre probe that can distinguish between breast cancer tissue and normal tissue — potentially allowing surgeons to be much more precise when removing cancerous tissue. The device could help prevent follow-up surgery, currently required by 15 to 20 per cent of breast cancer surgery patients, when all the cancer is not removed.
Researchers at the University of Adelaide in the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), the Institute for Photonics and Advanced Sensing and the Schools of Physical Sciences and Medicine describe that the optic probe works by detecting the difference in pH levels between the two types of tissue. The research was conducted in collaboration with the Breast, Endocrine and Surgical Oncology Unit at the Royal Adelaide Hospital.
“We have designed and tested a fibre-tip pH probe that is very sensitive for the differentiation between healthy and cancerous tissue with an extremely simple — so far experimental — setup that is fully portable,” says project leader, Dr Erik Schartner, postdoctoral researcher at the CNBP at the University of Adelaide. “Because it is cost-effective to do measurements in this manner, compared to many other medical technologies, we see a clear scope for this technology in operating theatres.”
Current surgical techniques to remove cancer lack a reliable method of identifying tissue types during surgery, relying on the experience and judgement of the surgeon to decide how much tissue should be removed. Therefore, surgeons often perform 'cavity shaving', which can result in the removal of excessive healthy tissue. However, at other times, some cancerous tissue might be left behind. “This is quite traumatic to the patient and has been shown to have long-term detrimental effects on the patient's outcome,” Schartner says.
The optical fibre probe uses the principle that cancerous tissue exists in a more acidic environment than normal cells, because they produce more lactic acid as a by-product of their aggressive growth. The pH indicator embedded in the tip of the optical probe emits a different colour of light depending on the acidity of the environment. A miniature spectrometer on the other end of the probe analyses the light and thereby the pH levels of the tissue.
“How we see it working is that the surgeon uses the probe to test questionable tissue during surgery,” says Schartner. “If the readout shows the tissue is cancerous, it can immediately be removed. Presently, this normally falls to post-operative pathology, which could mean further surgery.”
The researchers currently have a portable demonstration unit and are doing further testing. They hope to progress the research to clinical studies in the near future.
The research, titled “Cancer Detection in Human Tissue Samples Using a Fiber -Tip pH Probe”, was published in issue 23 in 2016 of the Cancer Research journal.