Frequency of Various Malignant Diseases in Children Younger Than 10 Years Old in Yazd

According to the results of studies from different parts of the world, malignancies in children are rare. Despite this fact, malignant neoplasms remain the second leading cause of death in children after accidents. ALL, CNS tumors and lymphomas are the most common malignancies in children. They account for approximately more than 50% of malignancies and occur more frequently in boys than girls. There are 2 peak incidences early childhood and adolescence in the < 19 years old age group. The distribution of malignant diseases in the pediatric age group on the basis of age and sex has been evaluated in this study. This descriptive – observational study was done by cross- sectional method from 1998 till 2003. We evaluated the frequency and distribution of malignant diseases in children younger than 10 years old according to age and sex in Yazd. The files of children whose malignancy was confirmed by the pathological reports were studied and data related to age, sex, type of malignancy and time of admission was entered in the questionnaires. Frequency and distribution of malignant diseases in male children < 10 years old is 60.4%which is more than females (39.6%). It is most frequent in children aged 6-7 years and least common in children<1 years of age. ALL has the highest frequency of distribution, while histiocytosis has the lowest. The other malignancies following ALL are as follows: Hodgkins lymphoma (8.5%), Neuroblastoma (8.5%) soft tissue sarcoma (7.5%) bone tumors (6.6%), Wilm’s tumor (6.6%), Germ cell tumors (3.8%), AML (2.8%), Retinoblastoma (1.9%), malignant neoplasms of the liver (1.9%) and Histiocytosis (0.9%). The frequency and distribution of malignant diseases in the pediatric age group is more common in males than in females which is the same as other studies. The frequency and distribution of malignant diseases is the most in children aged 6-7 years that is different from other studies. ALL is the most prevalent malignant disease in the pediatrics age group followed by Hodgkins lymphoma and CNS tumors.