Terabotics - terahertz robotics for surgery and medicine

There is a pressing need to improve the precision, control and selectivity of surgical procedures addressing several high-incidence cancers. For example in the UK, the incidence of basal cell carcinoma (BCC) has increased by approximately 250% since the 1990s, with 137,000 new cases of BCC each year. Bowel cancer is the 4th most common cancer and is the second most common cause of cancer death. Some 15% of new bowel cancer cases are early stage and amenable to potential endoluminal surgery; this proportion is increasing with national screening programs. Delayed diagnosis and incomplete excision of tumours are key drivers of patient morbidity, and squander limited surgical resources. Streamlining screening and early diagnosis processes is now even more important with more patient backlog caused by Covid-19. The default surgical practice is to remove cancers wherever possible, along with a margin of healthy tissue. Leaving cancer cells behind leads to reoccurrence, but removing too much healthy tissue increases both the risk of complications and the loss of normal function. Trying to optimise this balance is a global challenge. For example, BCCs often spread out beneath the surface of the skin such that their entirety cannot be detected until surgery. Moh's micrographic surgery is the gold standard for treating BCCs: the tumour is removed section by section and examined under the microscope until no further tumour can be seen. This is both time consuming and traumatic for the patient, typically resulting in larger skin grafts than expected. If the extent of the tumour could be accurately determined, using terahertz (THz) imaging prior to surgery, the procedure would be faster, and grafts better planned. Similarly, if a diagnostic THz imaging capability could be added to a flexible endoscope, more colorectal tumours could be identified in situ and resected without waiting for histology results (typically 2 weeks) and a follow-up procedure.

In this programme, a highly interdisciplinary team consisting of investigators at Universities of Warwick, Exeter and Leeds in Physics, Engineering and Medicine, and at the University Hospital of Coventry and Warwickshire and the Leeds Teaching Hospitals NHS Trust, join forces to optimise patient diagnosis and treatment. The team is supported by industry partners including TeraView Ltd, Intuitive Surgical, Kuka (world leader of industrial robots), QinetiQ, the National Physical Laboratory and Lubrizol (an international cosmetics company).

THz light is non-ionising, uses low power levels such that thermal effects are insignificant and is consequently safe for in vivo imaging of humans. It is very sensitive to intermolecular interactions such as hydrogen bonds, and probes processes that occur on picosecond timescales. Owing to the high sensitivity of THz light to tissue hydration and composition, THz spectroscopic imaging can help locate and diagnose lesions that cannot be seen by other imaging modalities. In Terabotics, we will integrate THz technology into robotic probes to develop improved platforms for cancer detection and surgical removal. We will develop probes that can be used on the skin as well as in the abdominal cavity and, by miniaturising the technology, we will also develop a new flexible probe for robotic colonoscopy. In this way the project will lead to more efficient cancer diagnosis and surgery, saving surgeons' operating time and reducing the number of surgeries needed. This is because accurately determining the extent of cancers prior to surgery will enable better surgical planning and reduce the need for a second surgery. Being able to diagnose cancers in situ will also give a faster diagnosis to treatment time. These factors will reduce trauma, costs, patient backlog and waiting lists, and improve patient outcomes.

In short, our breakthrough in developing in situ diagnosis will bring step changes in the detection and treatment of cancer for many years to come.