Understanding Childhood Cancer

Childhood cancer is a significant concern in India, with an estimated 75,000 children developing cancer annually. However, it represents a smaller proportion compared to adult cancer cases, which number around 14 lakhs annually in India. This article delves into some of the important aspects of childhood cancer, highlighting its types, warning signs, causes, diagnosis, treatment options, and post-treatment prospects.

Childhood Cancer Types

Childhood cancer encompasses various types, including:

1. Acute Leukemia: The most prevalent childhood cancer affecting the bone marrow and blood. Also called blood cancer.
2. Brain Tumors: The second most common among pediatric cancers.
3. Neuroblastoma: Emerging from early nerve cell forms in developing embryos, it is predominantly found outside the brain. It often affects the adrenal gland, present above the kidneys.
4. Wilms Tumor: Originating in one or occasionally both kidneys.
5. Lymphomas: Arises from lymphocytes (type of immune cells), often originating in lymphatic tissues such as lymph nodes. It can also impact the bone marrow and other organs. The two primary types are Hodgkin lymphoma and non-Hodgkin lymphoma (NHL), with most NHL cases in children being high-grade.
6. Rhabdomyosarcoma: Developing from cells that typically transform into skeletal muscles, it is one the most common soft tissue sarcoma in children.
7. Retinoblastoma: An eye cancer often characterized by a white or pinkish pupil.
8. Bone Cancers: Mainly Osteosarcoma and Ewing sarcoma, originating within bone tissues.

Warning Signs of Pediatric Cancers

Symptoms may vary, but common indicators include:

• Recurring or persistent fevers with an unknown cause.
• Unexplained and continued weight loss.
• Headaches, often accompanied by early morning vomiting without nausea.
• Persistent pain in bones, joints, back, or legs.
• Painless lumps or masses, especially in the abdomen, neck, chest, pelvis, or armpits.
• Excessive bruising, bleeding, or the development of rashes.
• A whitish appearance behind the pupil.
• Consistent fatigue or noticeable paleness.

Causes

• About 90% of childhood cancers have no known preventable cause and are attributed to random DNA and genetic defects, unlike adults, where lifestyle and environmental factors like smoking, obesity, and tobacco contribute to congenital conditions.
• In 10% of childhood cancer cases, the cause may be an inherited genetic mutation from parents.
• Possible associations with environmental exposures such as parental smoking, home pesticide exposure, and radiation have been noted. However, the cumulative risk from these factors remains extremely low in children. Studies are ongoing to find out the role of other factors like nutrition.

Diagnosis

Childhood cancer is highly curable, in 80 per cent of cases in the Western world, especially when detected early. Diagnosis methods include:

• For blood cancer, diagnosis involves bone marrow examination, supplemented by specialized tests like flow cytometry to identify the specific type of blood cancer.
• Solid tumours require imaging (ultrasound/CT scan/MRI) to determine their extent, followed by biopsy. Biopsy samples are microscopically examined to identify cancer cell types. Special markers (immunohistochemistry) differentiate between various tumour types, and genetic tests help with risk assessment.
• Some of the tumours may be picked up with the help of tumour markers. These are the chemicals released by the tumour in blood, and the levels of these biochemical markers in blood may help in diagnosis and monitoring of response to treatment.

Treatment

Treatment strategies are tailored to each cancer type, involving three main modalities used in varying combinations:

• Chemotherapy: Medications designed to target and kill cancer cells, chemotheraphy commonly used for blood cancers.
• Surgery: Often utilized to remove solid tumors.
• Radiation: Required in some cases to complement treatment.
• Bone Marrow Transplant: This is needed in rare advanced cases of blood cancer, which are not responding well to chemotherapy. Also, for certain high-risk solid tumours, bone marrow transplant constitutes an important part of treatment.

It's crucial to note that many childhood solid tumours necessitate chemotherapy for a cure, even if surgery has removed the tumour completely. Early diagnosis and comprehensive treatment at specialized facilities are key to successful outcomes.

Post-treatment Scenario

Following successful treatment, children can resume normal lives. They can interact with peers, attend school, and even start families of their own. Life expectancy returns to normal if cancer is cured. However, some long-term side effects may occur in rare cases, necessitating regular clinical follow-up after completing therapy.