<qa>  What is the main reason for the increase in cancer survivors?During the past 30 years, survival of breast cancer patients has improved substantially due to earlier diagnosis, improved surgical techniques, introduction of new combination of chemotherapy, new hormonal treatment, introduction of targeted treatment, and refinement of radiation techniques. With increasing number of cancer survivors, which in part are reached by more aggressive treatment, more attention is presently being drawn to long-term consequences of curative cancer treatment. 