**2.2 Colorectal cancer caused a premature death**

These characteristics suggest that an epidemiological study must be performed: Colorectal cancer caused thousands of deaths in Vietnam, and it was considered as one of the most important public health problems in our country.

Causality and risk factors of colorectal cancer were presented at nationwide because the cancer was observed in all 671 districts within all 63 provinces/cities. Therefore, we should observe and examine etiology and causality at the household and community levels in identifying and controlling risk factors.

Registration of colorectal cancer mortality nationwide might be underreported for about 40% of total cases. Data on cancer mortality registration will promptly be improved and it will be used for cancer control and prevention in our country.

Using referred data of cancer from China to estimate the cancer incidence and mortality of all sites as well as of colorectal cancer, it might be an overestimated colorectal cancer in 2002 for Vietnam [25].

• Colorectal cancer caused premature death for an average of 7.3 years [18].
