Cancer is the second major cause of mortality in children over the age of one year in many nations, behind only accidents. The incidence rate of all malignant tumors in children under the age of 14 is 12 per 100,000. Thankfully, much progress has been made in the management of childhood cancer in latest years, to the point that there are few specialties that can offer therapeutic outcomes similar to pediatric oncology in the previous twenty years.
A good example is an acute leukemia, a condition that was once thought to be invariably fatal but now has sporadic but unsustainable short remissions. Acute lymphoblastic leukemia, the most common childhood cancer, now has a five-year survival rate of more than 75%, indicating that the majority of patients can be cured.
In the treatment of solid tumors, similar advancements have been achieved. When surgery was the main therapy option, two-year survival rates ranged from 5% to 20%, with extremely significant perioperative mortality. Soon after radiation therapy was established as a systematic treatment in pediatric oncology, positive findings in Hodgkin's disease and Wilms' tumor started to emerge. Chemotherapy, on the other hand, started to be used as a last choice for relapses; but, once its efficacy had been shown, it was utilized as a third treatment option, in addition to surgery or radiation therapy. What is certain is that since these approaches have been combined, the long-term survival of children with cancer has increased dramatically.
As a result of this achievement, new standardized clinical procedures have been developed, allowing researchers to resolve doubts and choose the most suited recommendations for each neoplasm and, more significantly, each patient's unique condition.
Given the complexity of medical advances, children with cancer should be directed to facilities with specialized human and technical resources and they can be managed by pediatric oncology specialists as soon as possible.
Childhood Cancer Epidemiology
In the United States, about 10,475 children under the age of 15 will be diagnosed with cancer in 2022. For the past few decades, childhood cancer rates have been steadily increasing.
Because of significant medical advancements in recent decades, 84 percent of children with cancer now live for five years or longer. Overall, the 5-year survival rate has increased dramatically since the mid-1970s, when it was at 60 percent. Despite this, survival rates vary widely depending on the type of cancer and other factors.
Cancer is the second major cause of mortality in children aged 2 to 14. After accidents, cancer is the second leading cause of death in children aged 2 to 14. In 2022, approximately 1,050 children under the age of 15 are estimated to die of cancer.
What are the differences between Adult and Childhood Cancers?
When cells within the body begin to grow out of control, cancer develops. Cancerous cells can arise in almost any part of the body and spread to other parts of the body. Although this is accurate for both childhood and adult malignancies, the forms of cancers that children are more likely to have and how they are treated vary.
The Types of Cancers are Different
Malignancies that originate in children are frequently distinct from cancers that develop in adults. Childhood malignancies are not substantially related to lifestyle or environmental risk factors, unlike many adult cancers. Only a small percentage of childhood cancers are caused by mutations in DNA passed down from parents to their children.
Treatment is often More Successful
Childhood malignancies, with a few exceptions, typically respond better to particular treatments. This could be due to differences in the tumors themselves, as well as the fact that children's treatments are generally more intensive. Furthermore, children rarely have many of the underlying health issues that adults with cancer may experience, which can often worsen with treatment.
Long-term Side Effects are More of a Concern
Children's bodies, on the other hand, are still developing, and they are more susceptible to have negative effects from certain treatments. Radiation therapy, for example, is more likely to impact children. Because many cancer therapies might have long-term negative effects, children who have had cancer will require ongoing monitoring for the remainder of their lives.
Most children and teenagers with cancer in the United States are treated at a Children's Oncology Group member center (COG). These facilities are all affiliated with a university or a children's hospital. These facilities provide the benefit of being treated by a team of professionals who understand the variations between adult and childhood cancers, as well as the specific needs of cancer patients and their families. Pediatric oncologists (children's cancer doctors), surgeons, radiation oncologists, pediatric oncology nurses, physician assistants, and nurse practitioners are generally part of this team. As we've learned more about treating childhood cancer, it's become even more essential that therapy be provided by specialists.
Psychologists, social workers, child life specialists, dietitians, rehabilitative and physical therapists, and educators are all available at these facilities to help and educate the entire family.
Every family member and practically every element of the family's life is affected when a child is diagnosed with cancer.
Childhood Cancer Types
The cancers most frequently affecting children differ from those affecting adults. The following are the most common cancers in children:
- Brain and spinal cord tumors
- Wilms tumor
- Bone cancer
Other types of malignancies are uncommon in children, but they do occur. Children may develop cancers that are considerably more frequent in adults.
The most prevalent childhood malignancies are leukemias, which are tumors of the bone marrow and blood. They account for roughly 30% of all childhood malignancies. Acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML) are the most frequent forms in children. Bone and joint pain, tiredness, weakness, pale skin, bruising or bleeding, fever, weight loss, and other symptoms are all possible indications of these leukemias. Because acute leukemias can spread quickly, they must be treated as soon as possible (usually with chemotherapy).
Brain and Spinal Cord Tumors
Brain and spinal tumors are the second most prevalent cancers in children, accounting for around 28% of all cancers in children. There are numerous varieties of the brain and spinal cord tumors, each with its own treatment and prognosis.
Most children's brain tumors begin in the lower brain, such as the cerebellum or brain stem. Headaches, sickness, vomiting, blurred or double vision, dizziness, convulsions, difficulty walking or handling things, and other symptoms are all possible. In both children and adults, spinal cord tumors are less prevalent than brain tumors.
Neuroblastoma begins in the early stages of nerve cell growth in an embryo or fetus. Neuroblastomas account for about 8% of all childhood malignancies. This is a malignancy that affects infants and young children. It is rare in children above the age of nine. The tumor can begin anywhere, but it is most commonly found in the belly (abdomen), where it causes swelling. Other symptoms, such as bone pain and fever, can also occur.
Wilms tumor (also known as nephroblastoma) begins in one of the kidneys or, in rare cases, both. It is most frequent in youngsters between the ages of 4 and 5, and it is infrequent in older children and adults. It can manifest as a bulge or lump in the stomach (abdomen). Other symptoms that the child may experience include fever, discomfort, nausea, and a loss of appetite. Wilms tumor makes up roughly 4% of all childhood malignancies.
Lymphomas begin in lymphocytes, which are immune cells. The lymph nodes or other lymph tissues, like the tonsils or thymus, are the foremost common sites for these malignancies to develop. They have the propensity to harm the bone marrow and other organs. Weight loss, fever, sweats, fatigue, and lumps (swollen lymph nodes) underneath the skin in the neck, armpit, or groin are all symptoms that depend on where cancer develops.
Hodgkin lymphoma and non-Hodgkin lymphoma are the 2 commonest kinds of lymphoma. Both forms are often seen in both children and adults.
- Hodgkin lymphoma makes up about 4% of all childhood malignancies. However, it is more common in early adulthood (typically in the 20s) and late adulthood. Hodgkin lymphoma is rare in children under the age of five. The methods of treatment that work best for this type of cancer in children and adults are relatively similar.
- Non-Hodgkin lymphoma accounts for around 6% of all childhood malignancies. It is more common in younger children than Hodgkin lymphoma, but it is still uncommon in children under the age of three. Non-Hodgkin lymphoma in children is distinct from non-Hodgkin lymphoma in adults. These malignancies develop quickly and require aggressive treatment, but they also respond to treatment better than other non-Hodgkin lymphomas in terms of survival.
Rhabdomyosarcoma develops from cells that would typically become skeletal muscles. This cancer can begin in almost any part of the body, including the head and neck, groin, belly (abdomen), pelvis, or arm or leg. It might result in pain, swelling, or a combination of the two. In children, this is the most prevalent type of soft tissue sarcoma. It accounts for roughly 4% of all childhood malignancies.
Retinoblastoma is a type of eye cancer. It is responsible for around 3% of all childhood malignancies. It is commonest in children under the age of two, and it’s uncommon in children beyond the age of six.
Retinoblastomas are usually discovered when a parent or doctor sees something strange in the child's eye. When you shine a light in a child's eye, the pupil (the dark spot in the center of the eye) appears red due to blood in the back of the eye vessels. The pupil of patients with retinoblastoma is usually white or pink.
Primary bone cancers (bone cancers that start in the bones) are more common in older children and teens, but they can occur at any age. They are responsible for around 4% of all childhood malignancies.
In children, there are two varieties of primary bone cancers:
- Osteosarcoma is most common in teens, and it usually originates near the ends of the leg or arm bones, where the bone is rapidly expanding. It frequently causes bone discomfort that worsens at bedtime or after the workout. It might also result in edema surrounding the bone.
- Ewing sarcoma is a type of bone cancer that is less common. It is most common in young teenagers. The pelvic bones, the chest wall (the ribs or shoulder blades), or the midpoint of the leg bones are the most frequent areas for it to originate. Bone pain and swelling are frequent symptoms.
Childhood Cancer Risk Factors
Lifestyle and Environmental Risk factors
Many types of cancer in adults are caused by lifestyle-related risk factors such as smoking, being overweight, not getting adequate exercise, eating a poor diet, and consuming alcohol. However, lifestyle factors are expected to play little role in childhood cancers because they take several years to increase the cancer risk.
Some types of childhood cancers have been related to a few environmental factors, such as radiation exposure. Some studies have indicated that certain parental exposures (such as smoking) may increase a child's risk of certain malignancies, although additional research is needed to confirm these claims. Most childhood malignancies have yet to be linked to environmental factors.
Genetic changes (Mutations)
Scientists have just recently begun to comprehend how certain mutations in our cells' DNA might cause them to become cancer cells. Our genes, which control practically everything our cells do, are made up of the molecule DNA. Because our DNA comes from our parents, we usually appear as if them. However, DNA has an influence on more than simply our appearance. It also has an effect on our chances of contracting certain diseases, such as cancer.
The cells' growth, division, and death are all controlled by genes.
- Oncogenes are genes that help cells grow, proliferate, or survive.
- Tumor suppressor genes are those that halt cell division, fix DNA errors, or cause cells to die at the appropriate moment.
DNA alterations that keep oncogenes turned on or turn off tumor suppressor genes can increase the risk of cancer.
Inherited Versus Acquired Gene Mutations
Some children inherit from their parents DNA variations (mutations) that enhance their risk of certain cancers. These alterations can be detected in the DNA of blood cells or other body cells, and they are present in every cell of the child's body. Some of these DNA mutations are merely associated with increased cancer risk, while others can result in syndromes with additional health or developmental issues.
However, inherited DNA alterations are not the cause of most childhood malignancies. They are caused by alterations in the child's DNA that occur early in life, often before birth. A cell must copy its DNA every time it splits into two new cells. This system isn't perfect, and mistakes do happen, particularly when the cells are rapidly growing. An acquired mutation is a type of gene mutation that can occur at any moment during one's life.
Acquired mutations are only seen in the cancer cells of the person and are not handed down to his or her offspring.
The causes of genetic alterations in some adult malignancies are sometimes known (such as cancer-causing chemicals in cigarettes). However, the reasons for most DNA alterations in childhood malignancies are unknown. Some may have external origins, such as radiation exposure, while others may have unknown causes. However, many are believed to be the consequence of random events that occur inside a cell without the presence of an external cause.
Childhood Cancer Symptoms
Many childhood malignancies are discovered early by a child's doctor, parents, or relatives. Cancers in children, on the opposite hand, might be difficult to detect early since the symptoms are often almost like those of far more common illnesses or accidents. Children frequently become ill or develop bumps or bruises, which could obscure the first signs of cancer. Cancer in children is uncommon, however, if your child exhibits unusual signs or symptoms that do not go away, such as:
- A bulge or swelling that is unusual
- Paleness and tiredness for no apparent reason
- Bruising or bleeding that is easy to develop
- a persistent pain in one part of the body
- Unexplained fever or disease that won't disappear
- Frequent headaches, frequently accompanied with vomiting
- Eye and visual changes that occur suddenly
- Sudden, unexplained weight loss
The majority of these symptoms are triggered by something other than cancer, such as an injury or incident. Still, if the child exhibits any of these symptoms, take him or her to the doctor to determine the cause and, if necessary, treat it. Depending on the type of cancer, other symptoms may appear.
Childhood Cancer Diagnosis
A complete blood count (CBC) test may be recommended by your child's doctor. These tests can aid in the diagnosis of cancer, the detection of blood cancers, and the monitoring of how therapy is proceeding and affecting your child's health.
The CBC tests white and red blood cells, as well as platelets, to see if the quantities are within normal limits. The doctors go through the test results with the family and read them thoroughly. They explain what the data mean and how they affect the diagnosis and treatment approach.
Scans use various types of energy to create images of what the inside of the body looks like. Some scans even produce three-dimensional images. Based on your child's symptoms, our specialists may recommend certain scans, such as:
- X-rays. These scans make a black-and-white image of the inside of the body using rays. X-rays can assist doctors in detecting cancer signs and monitoring treatment outcomes.
- Ultrasound. Sound waves are used by an ultrasound machine. Doctors can create a representation of the body part suspected of having cancer.
- Computed tomography (CT) scan. This scan employs X-rays to take photos and build a three-dimensional image. Doctors can examine the patient for malignancies or other unusual structures.
- Magnetic resonance imaging (MRI). Magnetic fields provide detailed images of the inside of the body in magnetic resonance imaging. This scan is used by doctors to determine the size of a tumor.
- Positron emission tomography (PET). This scan uses a little amount of radioactive chemical that is taken by cancer cells to provide images of internal organs and tissue. It's sometimes used in conjunction with a CT scan.
- Radioisotope studies. Doctors utilize radioisotope tests to discover abnormal cells in the body. They inject a tracer, which is a material containing minuscule amounts of a radioactive chemical, and monitor its movement throughout the body.
Biopsy and Other Techniques
Doctors may need to perform minor surgery to help in the diagnosis of cancer. The following are some of the more prevalent cancer surgeries:
- Biopsy. The child's doctor may take a small sample of tissue from the area where the cancer is suspected to be present. Biopsies can be taken from several regions of the body. A pathologist analyzes the sample under a microscope to detect if cancer is present. A pathologist is a doctor who specializes in interpreting lab findings.
- Bone marrow aspiration or biopsy. A doctor takes a sample of bone marrow, the tissue found inside many bones, with a needle. The doctor takes a sample of the liquid, solid tissue, or both of the bone marrows' components.
- Lumbar puncture. A needle is used to extract fluid from the spine during a spinal tap. Doctors can look at the fluid to discover if cancer cells are present. They can also screen for tumor markers, which are chemicals found in the spinal fluid of cancer patients.
Other Specialized Cancer Tests
Some cancer tests examine specific characteristics of cells, such as genetic abnormalities in your child or a tumor. These tests include the following:
- Flow cytometry and immunohistochemistry. These techniques detect the type of protein in or on cells by using bone marrow or body fluids. This information is used by doctors to further define and categorize malignant cells.
- Genetic testing. Pediatric cancer is linked to a recognizable genetic mutation passed down through families in roughly 12% of instances. If physicians feel this is the case, they can talk to you about genetic testing. If you already know that a gene mutation that increases the risk of certain malignancies runs in your family, testing may be beneficial.
- Tumor sequencing. Tumor genes can change or mutate, allowing them to grow. Doctors can detect known mutations and find medications that particularly target them by taking tissue from a tumor. This assessment is sometimes referred to as molecular testing, genomic sequencing, and other related terms.
Childhood Cancer Treatment
Chemotherapy is a treatment that employs chemicals to help cancer cells die. Chemotherapy, on the other hand, can harm healthy cells as well as malignant cells. Hair loss, nausea and vomiting, mouth ulcers, low blood counts, and loss of appetite are all possible side effects. The severity of side effects varies with medication, but they normally subside once treatment is completed.
High-energy x-rays are used in radiation treatment (also known as radiotherapy) to kill or destroy cancer cells, preventing them from growing and replicating. Radiation therapy kills cancer cells, but it can also kill healthy cells in the treated area.
The radiotherapy technician starts planning before beginning radiation therapy. This entails determining the precise location in which the child should be placed. The part of the body where the child needs therapy will be marked with little markings. This permits radiation therapy to be administered in the same location each time. Each session of radiation therapy normally lasts a few minutes.
Side effects of radiation therapy vary depending on how much is administered, which region of the body is being irradiated, and will be explained in detail prior to treatment.
Childhood Cancer Surgery
At the time of diagnosis, surgery may be utilized to remove all or part of a tumor. The type of operation a child undergoes is determined by the type of cancer he or she has.
Stem Cell Transplant
When the doses of chemotherapy are so severe that the cells in the bone marrow are irreversibly damaged, a stem cell transplant is utilized as a part of various cancer treatments. A stem cell transplant is also used if the child's bone marrow has cancer cells.
Depending on the type of cancer, the transplanted cells may come from the child's own cells, a relative, or someone unrelated to the child.
Complementary and Alternative Therapies
Parents of children with chronic diseases or cancer frequently seek complementary and alternative treatments for their children.
Massage, meditation, and other relaxation techniques are examples of complementary therapies that are used in conjunction with medical interventions. Some complementary treatments can help children cope with the challenges of having cancer and undergoing cancer treatment.
Alternative therapies are unproven treatments that include herbal and dietary remedies in place of medical treatment.
Be aware that many unproven remedies are promoted on the internet and in other places with no monitoring or regulation. Consult your doctor or a hospital pharmacist before deciding on an alternative treatment.
The majority of childhood cancers have unknown causes and are life-threatening diseases. In long-term survivors of pediatric malignancies, the clinical benefits of continuously rising tumor control and survival rates are balanced by severe and deadly health consequences from genotoxic therapy. Iatrogenic second primary cancers are the most difficult for patients to deal with. As a result, the decrease of genotoxic treatments and the adoption of targeted or immune-based oncologic techniques are of significant clinical interest, especially in childhood cancer patients. The ability to adapt oncologic therapies for high-risk patients and intensify follow-up with intervention programs and multidisciplinary care is made possible by understanding therapy-associated as well as intrinsic risk factors for late sequelae of antineoplastic therapies, including secondary primary malignancies.