Researchers at the National University of Singapore (NUS) have developed a screening tool which could speed up and improve cancer diagnoses.

The device consists of a probe, which is inserted orally into a patient's body, and software to analyse what it detects.

It can immediately tell doctors whether a particular patch of tissue is cancerous without the need for a biopsy, and even alert patients to changes in tissue that might herald cancer - despite the area looking completely normal.

Conventional methods of diagnosing cancer depend heavily on how the pathologist interprets what he or she sees, said Professor Ho Khek Yu, head of the Yong Loo Lin School of Medicine's department of medicine. Doing so is time-consuming and might not always be accurate.

"Whenever we use the human eye, accuracy is subject to human ability," Prof Ho said. "You can get a different diagnosis, depending on the person's training."

The new technology makes cancer diagnosis much less subjective because it relies on tissue analysis at the molecular level.

The probe is able to detect the pattern of vibration in molecules. This pattern is subtly different for cancerous and non-cancerous tissues, which helps the probe distinguish between them.

To "teach" the device the differences between various cancer types, the NUS researchers carried out clinical trials on more than 500 patients to build a database.

While the team focuses mainly on gastrointestinal cancers such as those of the stomach and oesophagus, it has also tested the tool on other cancers like that of the cervix.

"The technology can be applied to any tissue site, as long as it can be accessed and we have the database for it," said Associate Professor Huang Zhiwei of NUS' department of biomedical engineering.

Prof Ho added that as the database grows larger, results "can approach 100 per cent accuracy".

The device was developed by NUS' department of biomedical engineering.

Cancer is the top cause of death in Singapore; one in three deaths is from the disease.

Two gastrointestinal cancers - of the stomach and colo-rectum - are among the top 10 most commonly found in men and women today.

The NUS team has plans to make its invention commercially available within the next five years, and eventually hopes to provide an alternative means of diagnosing cancers.

"Currently, pathology is still the gold standard," Prof Ho said. "But you may not necessarily need pathology all the time. We are hoping in the future this will replace it."