Digistain mid-IR Cancer detection technology; a calibration and validation study.

Most cancers are first discovered when they manifest themselves physically. In the case of breast, a lump is found, and a biopsy is taken with a hollow needle. The tissue sample is fixed in formalin, embedded in wax, and slices are stained with dyes and mounted on a microscope slide. The slide is then visually evaluated using an optical microscope, using a long-established protocol, to decide its grade and how far the disease has progressed.

The grading is a subjective process, however, and trials show that 2 different pathologists only agree, in the case of Breast Cancer, ~70% of the time. They respond to this uncertainty by over treating and giving chemotherapy when it may not be needed. This is dangerous and a 2009 national patient enquiry concluded it was the **primary cause of death in 27% of cancer deaths** in the UK.

Digistain measures the biopsy tissue's absorption of mid-infrared light at wavelengths corresponding to the proteins and the DNA. The DNA fraction can then be quantified in a Digistain index (DI), a well-known biomarker (aka nuclear-to-cytoplasmic ratio, NCR), because it elevates in Cancer when the cells divide more frequently and make more DNA than do healthy cells. Digistain is objective, and the added security it brings allows chemotherapy to be avoided when it is not needed.

The Digistain test fits very well into existing H+E pathology workflows and adds no patient procedures. Also, the preserved biopsies are archived in hospitals, complete with medical follow-up records. This allows Digistain to be trialled over large patient cohorts post hoc, in a comparatively quick and inexpensive way. This has accelerated its path to market where it now right now has approval for Breast. We now seek acceptance by NICE, the body that authorises treatments on the UK NHS system.

This project will establish standard samples that will allow us to test Digistain machines and validate that the DI data they generate are trustworthy enough to be used as the basis for have life-changing treatment decisions

Because it uses the NCR, there is good reason to believe that Digistain will also be effective in many other types of cancer. A recent independent analysis, funded by Innovate UK, has concluded that were it to be adopted across the NHS, for Breast Cancer alone, it would result in savings of £287M per annum, 450 tonnes of CO2, and 1266 life-years