Cool way to kill tumours in kidney cancer patients

When the probe is inserted into a kidney tumour and cooled rapidly to 40 deg C below zero, the tumour freezes - as does the water surrounding the probe in the demonstration above. When the probe is warmed up again, the frozen water in the cancer cell
When the probe is inserted into a kidney tumour and cooled rapidly to 40 deg C below zero, the tumour freezes - as does the water surrounding the probe in the demonstration above. When the probe is warmed up again, the frozen water in the cancer cells melts and expands, destroying the cells completely. -- PHOTO: LIANHE ZAOBAO
When the probe is inserted into a kidney tumour and cooled rapidly to 40 deg C below zero, the tumour freezes - as does the water surrounding the probe in the demonstration above. When the probe is warmed up again, the frozen water in the cancer cell
When the probe is inserted into a kidney tumour and cooled rapidly to 40 deg C below zero, the tumour freezes - as does the water surrounding the probe in the demonstration above. When the probe is warmed up again, the frozen water in the cancer cells melts and expands, destroying the cells completely. -- PHOTO: LIANHE ZAOBAO

A new method of destroying tumours may give hope to kidney cancer patients who cannot undergo surgery.

In fact, recovery is almost immediate, and patients stay in the hospital for a much shorter time.

The procedure involves inserting a probe into the tumour and rapidly cooling the probe to 40 deg C below zero.

The temperature is then raised, causing the frozen water in the cancer cells to expand and destroying them completely.

Tan Tock Seng Hospital is the first in Singapore to use this technique. It began performing the procedure in February. It has carried out the procedure on three patients so far.

"Sometimes patients may be too old or have too many problems to undergo surgery," said Dr Png Keng Siang, a consultant at the hospital's department of urology.

Typically, surgery to remove tumours on the kidney is done via robot, as it is a challenging area to operate on.

While this process is also minimally invasive, patients who have other complications such as diabetes or stroke may not be suitable.

The new procedure, on the other hand, is safe for use on patients even in their 80s and 90s. It takes about an hour, and patients need to stay only one night for observation.

Within the year, doctors say, it will become a day surgery procedure. There are similar techniques used to remove tumours on the liver, for instance, but these use heat.

"The cold means it's less painful for the patient than heat-related techniques," said adjunct assistant professor Pua Uei, a consultant with the department of diagnostic radiology.

The new technique is not intended to replace conventional robotic surgery, but to give patients who cannot undergo surgery an option they would otherwise not have.

"It causes a lot of anxiety otherwise," said Dr Png. "Every day you live with the knowledge that you have a cancer inside you."

LINETTE LAI