• Leukemias are cancers of the blood. These are the most common forms of cancer among children, accounting for about 30% of all childhood cancers. Acute lymphocytic leukemia (ALL) and acute myelogenous leukemia (AML) are the most common types of leukemia in children.
• Solid tumors are cancers of the bone, organs, or other tissues in the body. Brain and other nervous system cancers are the 2^nd most common cancers in children, making up about 22% of childhood cancers.
• Lymphomas are cancers of the lymph system. Non-Hodgkin's Lymphoma (e.g. Burkitt's, non-Burkitt's, and lymphoblastic lymphoma) is the 3^rd most common childhood cancer. It occurs most often in children between 2 and 10. Hodgkin lymphoma (sometimes called Hodgkin disease, Hodgkin's disease, or Hodgkin's lymphoma) generally affects children aged 15 and over.

DIFFERENCES BETWEEN PEDIATRIC AND ADULT CANCER

Childhood cancers differ from adult cancers in pathology, appearance, and rate of growth.

Cancers in children...

• usually grow in different types of body tissue. For children, cancers of the blood and bone marrow, lymph tissue, brain, nervous system, muscles, kidneys, and bone are most common. The most common sites of cancer in adults are skin, breast, prostate, lung, bowel, bladder and colon.
• occur significantly less often than in adults.
• typically result from unknown causes. In contrast, known causes of adult cancers include environmental, occupational and lifestyle factors, such as diet, alcohol and smoking.
• typically are more advanced at diagnosis than in adults.
• are more responsive to therapy than cancer in adults. Typically, childhood cancers respond well to treatment and children with cancer have a better chance today of living a longer life than ever before. There has been a steady decline in the mortality rate for cancer of children over the last 20 years. The overall cure rate for children falls in the area of 75%, while the cure rate for adult cancers is approximately 50%. Despite the significant progress, cancer remains the #1 cause of death by disease among children.
• are associated with increased likelihood of after effects from treatment. While many of the same interventions (e.g., chemotherapy, radiation and surgery) are used to treat childhood and adult cancers, children are more apt to suffer significant after effects (e.g., cognitive dysfunction, cataracts and organ failure) as a result of the harsh impact of the treatment on their young and developing bodies.
• occur during a period of growth and development for children. A key difference is that the cancer is affecting a developing child. Such developmental considerations must be kept in mind throughout the process of treatment.

MEDICAL TREATMENTS FOR CANCER

Treatment for childhood cancers can include chemotherapy, radiation, surgery and bone marrow and stem cell transplants. Childhood cancers can be treated with a combination of these treatments, chosen based on the type and stage of cancer.

HOW CAN PSYCHOLOGY HELP?

Psychologists make valuable contributions to the understanding and care of families faced with pediatric cancer. They have a strong and growing presence in children's cancer treatment programs. Psychologists collaborate with other health care providers and provide consultation to community partners and schools to deliver psychological support to patients, families and staff. This care is an integral part of comprehensive cancer treatment.

In addition, psychologists have expertise in research design and assessment that can improve professionals' understanding of the impact of cancer on children and families and inform the development of empirically based interventions to ameliorate difficulties.

Psychologists can play an important role throughout the entire process of a child or adolescent's experience with cancer, including:

• the initial time of diagnosis;
• throughout treatment;
• at the end of treatment;
• after treatment ends;
• at times of relapse;
• at the end of life.

Psychologists can provide the following important services to pediatric cancer patients and their families:

• assessment and treatment of behavioural, cognitive, and emotional problems associated with pediatric cancer diagnosis and treatment;
• neuropsychological assessment to understand how cancer (e.g., brain tumors) and cancer treatments (e.g., chemotherapy and radiation to the brain) affect cognitive and academic skills;
• program development of evidence-based interventions for children and adolescents treated for cancer, their parents and their siblings;
• bereavement counselling and treatment;
• consultation to staff, families, and school staff regarding health promotion and treatment of behaviour and emotional difficulties, as well as the accommodations and interventions needed to address cognitive and academic difficulties. 

The Children's Oncology Group (COG: Noll & Kazak, 1997) has specified guidelines for standard psychosocial care for pediatric cancer. This includes recommendations for services across all phases of treatment, including ongoing attention to clear communication with families about the disease, elements of treatment, and medical decision making; management of affective (e.g., anxiety), behavioural (e.g., adherence), and physical (e.g., pain, nausea) difficulties associated with invasive procedures and chemotherapy; school reentry and other academic needs (e.g., neuropsychological assessment for acquired learning problems); and coping with relapse, death and bereavement. Ultimately, the needs of both children and families should be given consideration.

UNDERSTANDING AND MANAGING PAIN

Pain in children with cancer can arise from many causes. For example, cancer cells in the blood or solid tumors in the body can cause bone or tissue pain. Further, medical tests (e.g., bone marrow aspirates and lumbar punctures) and some side effects of cancer treatment (e.g., chemotherapy, radiation), such as mouth or skin sores can be painful.

The experience of pain is complex and multi-factorial in nature. A child's pain, and accompanying distress, has been found to be related to many different factors, including previous pain experiences, age and developmental level of the child, level of parental anxiety or distress, level of social support, current coping skills, and perceived control (Zeltzer, 1994).

Psychologists can provide a range of interventions (e.g., preparation, desensitization, imagery, relaxation, modeling, distraction, and positive reinforcement) to help children undergoing invasive and painful procedures as part of their cancer care. The integration of these approaches with other interventions (e.g., pharmacologic) has proven highly effective in helping pediatric oncology patients to manage their pain.

Psychologists can help children with procedural distress, pain, nausea and vomiting (Morrow, Hoagland & Morse, 1982). Research supports the use of behavioural interventions (e.g., distraction, relaxation) for reducing chemotherapy side effects and anticipatory nausea (McQuaid & Nassau, 1999). Behavioural pain management and relaxation have been found to reduce anxiety and pain during invasive medical procedures (e.g., starting intravenous lines, lumbar punctures, and bone marrow aspirations; Powers, 1999).

TREATING LONG-TERM CONSEQUENCES

With increasing rates of survival in pediatric cancer, there has been a parallel increase in our appreciation for the medical and psychological sequelae of childhood cancers and their treatments. Cancer treatment can cause side effects ("late effects") that may occur years after treatment has ended. The risk of late effects depends on the type and amount of treatment that the child receives. On average, 75% of children with cancer survive, but approximately 50% of survivors are faced with significant late effects as a result of their disease and its treatment.

Late effects can include: growth impairment, sterility, cardiac complications, organ damage, neurocognitive impairments, secondary cancers, and more. These sequelae can in turn affect social functioning and relationships, academic success, employment, personal functioning, and family functioning.

The full impact of cosmetic, medical, and functional limitations may not be apparent immediately after completion of cancer treatment, and the significance of these deficits and their impact on development may evolve over time. Consequently, After-Care Clinics have been established to (a) promote health and health education, and (b) monitor survivors at regular intervals for potential late effects so they can be both identified and treated as early as possible.

The development of late effects from pediatric cancer treatment provides important opportunities for psychosocial interventions, particularly for subgroups of children at high risk for persistent difficulties. Psychologists play an important role as part of the After-Care team, providing screening, assessment, referral, and/or intervention for survivors presenting with a range of psychological difficulties.

With an increasing number of children becoming long-term cancer survivors, it has become evident that these survivors are experiencing long-term neurocognitive deficits (e.g., learning disabilities, cognitive deficits, attention disorders, and difficulties with memory). Impairments in memory, processing speed, and attention occur in up to 40% of long-term survivors of pediatric cancer and can adversely affect academic, social, and vocational functioning (Krull et al., 2008). Neuropsychologists evaluate, monitor and assist childhood cancer survivors who are at risk of neuropsychological sequelae, as a result of their disease (e.g., brain tumors) or treatment (e.g., chemotherapy and/or radiation to the brain).

APPRECIATING DISTRESS AT DIAGNOSIS AND OVER TIME

A diagnosis of childhood cancer in the family is a traumatic event that typically triggers a range of emotional responses. The largest area of work in pediatric oncology research has examined the psychological reactions of patients and parents during the course of active cancer treatment.

Longitudinal work suggests that children who have been (a) recently diagnosed and are (b) in the early stages of treatment experience increased levels of distress compared with healthy comparison children (Sawyer et al., 1997). Studies have found that this distress tends to be high at diagnosis (an understandable and normal response to the distressing circumstances) and decreases over time.

Cancer creates many changes and challenges for children and their families. Children of different ages understand and react differently to cancer and its treatment. The child's personality, normal coping style, support system, treatment plan, as well as age or developmental level will affect how he or she copes with cancer.

Many factors (e.g., previous life experiences) can affect how one copes with the current crisis and early adaptive adjustment is associated with adjustment over time. Successful coping provides relief from both short and long-term stress and leads to adjustment and adaptation. When other life stressors, such as death, loss of a job, moving, marital problems, divorce, emotional problems, or substance abuse existed prior to the cancer diagnosis, the situation may be even more difficult to cope with.

Psychologists can support and assist patients and families in effectively coping with the distress associated with the cancer diagnosis and treatment over time.

THE IMPORTANCE OF SOCIAL RELATIONSHIPS: FAMILY AND SCHOOL

Children are members of many communities, including families, neighbourhoods, and schools, and their continuing role in these communities should be maintained.

A child's diagnosis and treatment for cancer occurs within the context of the family system and has great potential for affecting parent, sibling, and family functioning. Caring for a child with cancer can require a significant change in the family system, with much of the family's attention and resources focused on the affected child. Siblings may also need to adjust to the decreased availability of their parents and assume greater responsibility at home.

School is an integral part of a child's life and it is essential they have ongoing opportunities to pursue education. It is also an important part in returning to a normal routine during and after cancer treatment. School also helps children to feel good about themselves and hopeful for the future.

Some children with cancer may find it hard to go back to school, especially if they have changes in their body (e.g., hair loss and weight loss, or weight gain). An important aspect of psychological care for pediatric cancer is to facilitate school reintegration. This may include going to the child's school to talk with the classmates and staff to explain what cancer is and how it is treated, assistance re-entering school community, and promoting adaptive functioning at school.

Individuals who experience cognitive sequelae as a result of cancer and associated treatment often benefit from:

• school interventions focused upon their learning strengths and weaknesses;
• specialized neuropsychological assessment by a neuropsychologist to evaluate, monitor and assist children at risk for neuropsychological sequelae, as a result of their disease (e.g., brain tumors) or treatment (e.g., chemotherapy and/or radiation to the brain). The evaluation can then be used to assist the child, parent and school teacher with the child's learning. Early intervention to address potential neurocognitive problems could promote future academic, vocational, and socio-emotional quality of life for childhood cancer survivors.

WHERE DO I GO FOR MORE INFORMATION?

More information on pediatric oncology and interventions can be found at CureSearch http://www.curesearch.org and Candlelighters http://www.candlelighters.ca.

You can consult with a registered psychologist to find out if psychological interventions might be of help to you. Provincial, territorial and some municipal associations of psychology often maintain referral services. For the names and coordinates of provincial and territorial associations of psychology, visit http://www.cpa.ca/public/provincialandterritorialassociations. The Canadian Register of Health Service Providers in Psychology also has a listing service and can be reached through http://www.crhspp.ca.

This fact sheet has been prepared for the Canadian Psychological Association by Lindsey Forbes, MA; Danielle Cataudella, Psy. D., C. Psych; and Cathy Maan, Ph.D., C. Psych.

Revised: August 2009