A leading cancer doctor says we need a plan to tackle rising numbers of the disease.

A study by Otago University and the Cancer Society predicts the number of those affected by the disease will increase by 50 percent in the next 15 years.

Our survival rates are already pitiful compared to the likes of Australia and Canada and cancer remains the leading cause of death in this country.

Epidemiologist Dr Diana Sarfati told Mike Hosking says cancer rates are increasing around the world.

"Where we are falling behind compared to other countries is the approach to planning and managing the cancer problem in New Zealand."

Diana Sarfati says we need to look at survival rates and inequality in survival rates which were exposed in the study.

"With the growth of the New Zealand population and the fact people will be getting much older, the study is pretty accurate."