Pediatric Cancer and Its Singularity

Pediatric cancers are defined as those that develop during and as the consequence of the complex process of physiological growth and development, while body growth is active. Most childhood cancers arise because of stochastic developmental errors compounded by inherited susceptibility. Environmental exposures related to pediatric cancer are weak and inconsistent. Germline mutations in cancer-predisposing genes are identified in 8.5% of children and adolescents with cancer. An estimated 430,000 new cases of childhood cancer are expected each year worldwide. Demographic trends show that the annual incidence of childhood cancer is projected to high-income countries and upper-middle-income countries showing a decline in cases, whereas cases will increase in low-income and low-to-middle income countries because of population growth. Childhood cancers represent the leading cause of disease-related morbidity and mortality in high-income countries. Estimates of 5-year survival for all cancers combined broadly range from only 7.4% in low-income countries to 79.8% in high-income countries. With the overall improvement of pediatric cancer survival rates, it has become evident that pediatric cancer survivors are at risk of accelerated physiologic aging. They have a high risk of early mortality from subsequent cancers, cardiac events, and pulmonary conditions.