Fast, painless way of detecting skin cancer

Dr Eileen Tan, dermatologist with Mount Elizabeth Novena Hospital.
Dr Eileen Tan, dermatologist with Mount Elizabeth Novena Hospital. PHOTO: DR EILEEN TAN

Getting tested for skin cancer used to mean a painful biopsy, followed by a long, anxious wait for the results.

But doctors at the National Skin Centre (NSC) are now able to tell if someone has the disease simply by looking at his skin through a special machine.

Unlike a biopsy, no stitches are needed and a diagnosis can be made in as little as five minutes.

In the past, said Associate Professor Steven Thng, patients would come in for a consultation and then be given an appointment for a biopsy several weeks later.

After the biopsy, which involves cutting off a piece of skin for examination under a microscope, they would have to wait another one or two weeks for the results.

The new machine saves patients the scarring and cost of a biopsy, said Prof Thng, a senior consultant at NSC. "Most of all, it saves (them) the stress of waiting for the results."

A biopsy can cost about $300. The new technique has been free so far because of research funding, but there are plans to charge for it, at a price yet to be determined.

The machine uses confocal imaging technology, which allows doctors to see in 95 per cent of cases whether someone has cancer. Some people can even go under the knife to have the cancer removed on the spot.

The centre began trying out the technology in December 2014, and started offering it as a full-fledged service six months later.

Skin cancer is among the top 10 cancers for men and women in Singapore, with 3,089 new cases reported between 2010 and 2014.

It is far more common among fairer-skinned Chinese, barely making it to the list of common cancers for Malays, and not appearing at all on the list of top 10 cancers among Indians.

Dermatologist Eileen Tan from Mount Elizabeth Novena Hospital said skin cancer rates are about three times higher in Chinese people than in Malays and Indians. This is because people who are darker have more skin pigment, which offers natural protection against ultraviolet (UV) rays.

The most common subtype of skin cancer here is basal cell carcinoma, followed by squamous cell carcinoma. Melanoma, which is the most deadly because of how quickly it can spread, is more common in the West but rare in Singapore.

Prof Thng said the good thing about skin cancer, compared with other cancers, is that it is generally very visible, making it easy for doctors to pick up.

Although skin cancer is on the top 10 list of frequently occurring cancers, it is not on the list of cancers with the highest mortality rates.

Dr Tan said skin cancer rates have been on the rise, as there were only 1,813 cases between 2003 and 2007. This spike could be partly due to our ageing population, she said, as skin cancer can take decades to develop and surface. It could also be a result of too much exposure to the sun.

"The hypothesis is mainly excessive exposure to harmful UV rays from the sun, increased indoor tanning, and lack of regular sun protection," she said.


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A version of this article appeared in the print edition of The Straits Times on November 02, 2016, with the headline 'Fast, painless way of detecting skin cancer'. Print Edition | Subscribe