Nutritional Background & BCG Scar Status in Children with Malignant Disease
The causes of most childhood cancer are largely unknown. The causal mechanisms for cancer in childhood as in adult involve an interaction of exposure with inherent genetic susceptibility. Prevention of cancer could avoid 80% of new cases. Immune system plays an important role in the defense mechanism against disease including cancer. BCG scar can be a good indicator for immune response. It is so important to determine the state of immunity in children prior to development of cancer as indicated by their response to BCG vaccination and to determine the nutritional background and their relation to BCG scar size. A casecontrol study was designed for these objectives. The total patient numbers were 120 cancer cases. Their controls were randomly selected from their neighbors matched for age and sex.
The study shows that negative BCG scars (diameters<1mm) are significantly more detected among cancer cases. And risk of cancer is more in children who are born with body weight of more than 4 kg Delayed introduction of complementary diet and delayed weaning are associated with reduction in risk of cancer. A significant reverse linear correlation is found between weight at birth and the diameter of BCG scars. While significant positive correlation is found between age at diet introduction and diameters of BCG scars.
So it is advisable to avoid early introduction of complementary diet within the first year of age and to delay weaning to the age of 2 years. The BCG scar can be a good indicator for the integrity of the immune system. It may be a worthy trial to revaccinate individuals for enhancement of immunity in children.