Bowel cancer in particular has risen by 50 per cent in 20, 30 and 40-somethings over the past 30 years. But now world-leading experts say they are seeing children with the disease. Bowel cancer in particular has risen by 50 per cent in 20, 30 and 40-somethings over the past 30 years. But now world-leading experts say they are seeing children with the disease.