- Leukaemia is a disease of the blood cells and represents 25% of all childhood cancers in Canada.
- The predominant type occurring in children is acute lymphoblastic leukaemia that affects the lymphocyte producing cells in the bone marrow.
Central nervous system tumours
- These tumours occur in the brain and spinal cord and are the second most common form of childhood cancer in Canada.
- They are much less diagnosed in many developing countries, partly due to lack of advanced diagnostic techniques.
- In Canada, brain and spinal cord tumours represent 17% of all childhood cancers
- Lymphomas are tumours of the lymphatic tissues and are the third most common cancer of children in Canada.
- Hodgkin’s lymphoma is slightly more common than Non-Hodgkin’s lymphoma in Canada.
- In Canada, lymphomas represent 16% of all childhood cancers.
Soft tissue carcinoma
- Soft tissue carcinoma includes rhabdomyosarcoma and fibrosarcoma.
- Rhabdomysarcoma is a cancer arising in cells that normally develop into skeletal muscles of the body. It is a typical soft tissue sarcoma of childhood that occurs more often in boys than in girls.
- Soft tissue carcinoma accounts for 6% of all childhood cancers in Canada.
- Neuroblastoma is a malignant disease of the sympathetic nervous tissue, originating in adrenal medulla or other sites.
- This form of cancer typically occurs in children younger than 5 years of age with more than ¼ of the cases showing up in the first year of life.
- This type of cancer represents almost 5% of all childhood cancers in Canada.
- Bone tumours arise in various types of cells of bone tissue and include osteosarcoma, Ewing’s sarcoma and others.
- Bone tumours represent about 5% of all childhood cancers in Canada.
- The most common renal cancer in childhood is Wilms’ tumour, occurring mostly in children under five years of age.
- Wilms’ tumour accounts for 4% of all childhood cancers in Canada.
- Retinoblastoma is cancer of the retina, the nervous tissue of the eye.
- About half of all cases are inherited.
- Its incidence peaks in the first year of life, and most cases are diagnosed before the age of 5.
- In Canada, retinoblastoma accounts for nearly 2% of all cancers diagnosed in children.
Source: Canadian Cancer Society, World Cancer Day: Childhood cancer in Canada, January 28, 2006. Available at www.cancer.ca