Colo-rectal cancer attacks the colon or the rectum.

The warning included a plea for people at risk of developing colo-rectal cancer to get checked. This applied especially to those aged 50 and over or those with a family history of colo-rectal cancer.

A coalition of medical associations yesterday launched a joint campaign to educate the public about this cancer and promote screening.

"It's a shame to see people die of this cancer because it is preventable. It is also curable if detected early enough," said Assoc Prof Parinya Thaivichaigarn, the chairman of the Society of Colon and Rectal Surgeons of Thailand.

Recent figures from the National Cancer Institute showed the incidence of colo-rectal cancer had been rising since 2000, said Parinya.

Doctors specialising in cancer epidemiology projected the

number of colo-rectal cancer patients would double in the next 10 years, said Prof Tanaphon Maipang, the vice chairman of Society of Surgical Oncologists (Thailand).

Cancer is the number one killer in Thailand and colo-rectal cancer is the third most common form in men and fifth in women. The highest incidence of this cancer is found in the Central region.

Colo-rectal cancer sufferers exhibited no obvious symptoms until the disease had reached a

late stage. Then intestinal bleeding and pain was present, said Parinya.

"It's a silent killer," he said. That was the reason most patients visited doctors when it was too late.

"In my life, I have found and treated only a few colo-rectal cancer patients who were in the early stages of the disease and all of those were diagnosed by chance, he said.

The survival rate for colo-rectal cancer patients after treatment varied depending on the stage of the disease. The earlier the cancer was detected, the higher the survival rate, said Parinya. The survival rate for stage-one patients was more than 90 per cent but by stage four that had fallen to just 5 per cent.

The changing diet of Thai people influenced by Western lifestyles was the main reason for the increased incidence of the disease, said Parinya.

"We have changed from eating Thai foods to Western foods and we're having diseases they have in the Western world," he said.

Genetic factors were responsible for a tiny proportion of cases only, he said.

To prevent colo-rectal cancer, doctors recommended a good diet, including avoiding sources of carcinogens such as burnt grilled or fried meat.

Regular checks were essential from the age of 50 onwards.

With the support of a pharmaceutical company, the medical associations would launch the two-year campaign to highlight colo-rectal cancer prevention and screening next month.

Arthit Khwankhom

The Nation