• Colorectal cancer, or cancer of the large bowel, has been the second most common cancer in both Singapore males and Singapore females since 1983. Its incidence almost doubled from the early 1970s to 1997 - from 19.9 to 37.5 per 100,000 in males and from 15.6 to 29.4 per 100,000 in females. Changes in dietary patterns affecting the bowel and increasing awareness leading to diagnosis are the most likely reasons for the rise in numbers.

• The most rapidly rising cancer is breast cancer; the incidence soared from 19.9 per 100,000 in 1968 to 46.1 per 100,000 in 1997. It was the most common cancer in women over the entire 30-year period studied.

  Women in Singapore tend to be diagnosed with breast cancer at an earlier age (between 45 to 49 years old) than those in the West (between 55 to 59 years old). The reason for this difference is unclear, although doctors have speculated that the increasing number of women delaying childbearing or deciding not to have children could be contributing factors. Most studies have also shown that women who develop breast cancer before menopause have a poorer prognosis than those with a later diagnosis.

• Non-Hodgkin's lymphoma has increased markedly, to around 150 cases per year in the late 1990s. It is now the eighth most common cancer among males. In the 1970s, it was fairly uncommon - only about 50 cases per year. Many Western countries have also seen a rising trend, although the reasons for the increase remain unclear.

• Liver cancer, the fourth most frequent cancer among males, affected them 3.4 times more frequently than it did females during the period 1993 - 1997. The incidence is on the decline, thanks to the government's efforts to immunise the population against hepatitis B, which has been linked to this cancer.

The Good News

All is not gloom and doom. The incidence of some cancers has shown a downward movement over the years. Cancer of the oesophagus has shown the steepest drop in frequency for both men and women. Others showing a decline are cancers of the stomach, liver, mouth, cervix, and nasopharynx. Lung cancer too has shown some abatement.