A NEW technique developed at the National University Hospital to detect cancer in its earliest stages is already giving some patients a head start in fighting the disease.

Called an “optical biopsy,” the technique can detect so-called pre-cancers - collections of a few hundred malignant cells lurking among millions of healthy cells - that usually fly under the radar of standard cancer screenings.

Normal biopsies involve slicing out tissue and testing the cells for cancer.

The hospital is conducting a trial on 58 patients, 12 of whom are now receiving treatment after the optical biopsy diagnosed them with early-stage cervical cancer.

Pap smears, the common method used to test for abnormalities like infection or cancer in the cervix, would not have detected these pre-cancers.

Using light waves near the infrared region of the spectrum, project leader Ass Prof Huang Zhiwei and his team were able to accurately detect early tumours deep beneath the tissue surface.

The radiation targets specific proteins and carbohydrates in the cells, explained Dr Huang.

Varying combinations of biochemical molecules create a “fingerprint,” which helps clinicians determine whether the cell is normal or not, he said.

Conventional methods of optical testing used normal white light or ultraviolet light.

White light allows doctors to view only late-stage tumours that have already caused abnormalities on the tissue surface.

UV light, meanwhile, cannot penetrate far into the tissue, making cancers hidden deeper than a few millionths of a metre in the tissue almost impossible to detect, explained Dr Huang.

The new technique can be applied to almost any cancer, but not without more clinical trials and further improvements to the hardware used, like better probes.

The results of their findings were published in the scientific publication, Journal Of Analytical Chemistry.

However, Prof Soo Khee Chee, director of the National Cancer Centre, cautions against simply relying on optical biopsies for diagnosis.