It is a misconception that cancer is rare in children and young people (CYP, aged <21 years), which contributes to GPs and paediatricians feeling inhibited from initiating cancer investigations until they are clearly progressive. This contributes to risk of delays in diagnosis and consequent adverse outcomes. As CYP constitute only 20%–25% of the population, it is estimated that a general practice will see a CYP with cancer every 1.8 years, an individual GP therefore may see only 1 per 5/10-year period.1 A recent review rephrased the risk of childhood cancer from a population perspective, to the risk for each child (Figure 1). This calculation shows that a child’s cancer risk rises from being very low (1 in 4700) in the first year of life, rising rapidly until 5 years of age (1 in 1000), achieving a moderate risk by 15 years (1 in 450) and a substantial risk by 20 years (1 in 320). These risks are comparable to risk of other common childhood conditions such as diabetes, epilepsy, and bacterial meningitis. Inherited factors play a part for a minority, associations with genetic conditions such as neurofibromatosis types 1 and 2, family cancer syndromes, and tissue overgrowth syndromes are established; rarer genetic mutations are being increasingly recognised.2
There is a demonstrable relationship between the age-incidence of different cancer types and the rate of physiological growth of the host tissues.3 The risk is highest in the first 5 years of life, when solid tumours and brain tumours together are more common …