Currently, in developed countries, cancer is the most frequent cause of mortality in pediatrics in patients older than one year. Thanks to advances in diagnosis, oncological treatment and support, survival in pediatric oncology has increased to around 80% at 5 years. This has increased the detection of long-term side effects and second tumors in long survivors, recently increasing concern and developing specific follow-up models for these patients in the USA. In this descriptive, cross-sectional and prospective study we analyze the data obtained from the first specific unit in Spain for long-term follow-up in pediatric oncology developed at the Hospital Infantil Universitario del Niño Jesús in 2017. The results reproduce what has been described in other recent series, except for later effects such as cardiological alterations underestimated in our sample due to the younger age of our survivors.