Kidney Cancer in Children: Understanding the Risks and Treatments

Understanding Kidney Cancer in Children

While cancer is relatively uncommon in children, it can still affect them. The American Cancer Society (ACS) estimates that a significant number of children under 15 years old receive a cancer diagnosis annually. Among these, kidney cancer, though less frequent than some other childhood cancers, is a notable concern. It is one of the more common cancers affecting children between the ages of 0 and 14 years. However, it's important to remember that kidney cancer accounts for approximately 5% of all cancers diagnosed in children under 15.

Types of Kidney Cancer in Children

The most prevalent type of kidney cancer in children is known as Wilms’ tumor, also called nephroblastoma. This specific type accounts for nearly 9 out of 10 kidney cancers found in children. Wilms’ tumors typically manifest in children between 3 and 5 years of age. They most often affect only one kidney (unilateral), but in some instances, they can involve both kidneys (bilateral).

Other less common types of kidney cancer can also occur in children:

• Mesoblastic nephroma: This type is often identified within the first three months of a baby's life.
• Renal cell carcinoma: While this is the most common kidney cancer in adults, it can also occur in children, particularly in older teenagers, and is more common than Wilms’ tumors in this age group.
• Malignant rhabdoid tumor of the kidney: This is an aggressive form of cancer that predominantly affects infants and toddlers.
• Clear cell sarcoma of the kidney: This type shares a similar age of diagnosis with Wilms’ tumors but has a greater tendency to spread to other parts of the body.

Symptoms of Kidney Cancer in Children

Recognizing the signs of kidney cancer in children is crucial for early detection and treatment. Some potential indicators include:

• A palpable lump in the abdomen: This mass can often be felt through the skin, sometimes noticed by parents during routine activities like bathing or dressing the child.
• Abdominal swelling or pain: The abdomen may appear swollen, and the child might complain of discomfort or pain in that area.
• Blood in the urine (hematuria): The urine may appear pink, red, or brownish.
• Fever: Persistent or unexplained fever can be a symptom.
• Nausea or vomiting: The child may experience frequent feelings of sickness or throw up.
• Loss of appetite and weight loss: A decrease in hunger and noticeable weight loss can be concerning signs.
• Constipation: Difficulty passing stools can also be associated with kidney tumors.
• High blood pressure (hypertension): In some cases, kidney tumors can affect blood pressure.

It's important to note that these symptoms can also be caused by other, less serious conditions. However, if you observe any of these signs in your child, it is essential to seek medical advice promptly.

Causes of Kidney Cancer in Children

The exact cause of kidney cancer in children is not fully understood. Cancer develops when cells in the body undergo changes in their DNA, leading to uncontrolled growth and division. While researchers have identified certain genetic changes associated with kidney cancers in children, not all affected children have these specific alterations. More research is needed to pinpoint the precise triggers for these cellular changes in young individuals.

Diagnosis of Kidney Cancer in Children

When kidney cancer is suspected, a doctor will initiate the diagnostic process with a thorough physical examination and a detailed review of the child's medical history. This initial assessment helps the doctor understand the child's overall health and identify potential areas of concern.

Following the physical exam, several diagnostic tests may be employed:

1. Imaging Tests:
   • Ultrasound: This non-invasive test uses sound waves to create images of the kidneys and surrounding organs, helping to detect tumors and assess their size and location.
   • CT Scan (Computed Tomography): A CT scan uses X-rays to produce detailed cross-sectional images of the body, providing a comprehensive view of the kidneys and any abnormalities.
   • MRI (Magnetic Resonance Imaging): An MRI uses magnetic fields and radio waves to generate highly detailed images, which can be particularly useful for assessing the extent of the tumor and its potential spread.
2. Blood and Urine Tests: These tests help evaluate kidney function, check for signs of infection, and detect the presence of blood or other abnormalities in the urine.
3. Biopsy: In some cases, a small sample of the tumor tissue may be removed (biopsy) and examined under a microscope by a pathologist. This is often done after initial treatment or surgery to confirm the diagnosis and determine the specific type of cancer.

Treatment for Kidney Cancer in Children

The treatment approach for kidney cancer in children is highly individualized and depends on several factors, including the type of cancer, its stage (how far it has spread), the child's age, and their overall health. The primary goal of treatment is to remove the cancer and prevent its recurrence.

Common treatment modalities include:

• Surgery: This is often the first line of treatment. The surgeon may remove the affected kidney (nephrectomy), and sometimes surrounding lymph nodes or other affected tissues. In cases where both kidneys are affected, the surgeon will aim to preserve as much healthy kidney tissue as possible.
• Chemotherapy: This involves using powerful drugs to kill cancer cells. Chemotherapy can be administered before surgery to shrink the tumor (neoadjuvant chemotherapy) or after surgery to eliminate any remaining cancer cells (adjuvant chemotherapy). It is a crucial part of treating Wilms’ tumors and other types of kidney cancer in children.
• Radiation Therapy: This treatment uses high-energy rays to kill cancer cells. It may be used in conjunction with surgery and chemotherapy, particularly for more advanced stages of the disease or certain types of kidney cancer.

Prognosis and Outlook

The outlook for children with kidney cancer has significantly improved over the years due to advancements in treatment. The survival rates vary depending on the type and stage of the cancer. For Wilms’ tumors, the overall survival rate is quite high, often exceeding 90% for localized disease. However, the outlook for anaplastic tumors can be less favorable, with survival rates ranging from 38% to 84%. Non-Wilms’ tumors have a more variable prognosis, with a 3-year survival rate of around 59% in some studies. Aggressive types like malignant rhabdoid tumors and recurrent non-Wilms’ tumors tend to have poorer outcomes, while low-risk tumors like mesoblastic nephroma have excellent survival rates, close to 100%.

Prevention

Currently, there are no known specific ways to prevent kidney cancer in children, as the exact causes are still being researched. However, maintaining a healthy lifestyle for the entire family, including a balanced diet and regular physical activity, can contribute to overall well-being and potentially reduce the risk of various health issues.

When to Consult a Doctor

It is essential to consult a pediatrician or a healthcare professional immediately if you notice any of the symptoms mentioned above in your child. Early detection and prompt medical intervention are critical for achieving the best possible outcomes for children diagnosed with kidney cancer.

Frequently Asked Questions (FAQ)

1. Is kidney cancer curable in children?

   Yes, kidney cancer in children, particularly Wilms’ tumor, is often highly treatable and curable, especially when detected early. Survival rates are very encouraging.

2. Can a child live a normal life after kidney cancer treatment?

   With advancements in treatment and supportive care, most children who have been treated for kidney cancer can go on to live full and normal lives. Long-term follow-up care is important to monitor for any late effects of treatment.

3. Are there genetic factors involved in childhood kidney cancer?

   While not all cases have a clear genetic link, certain genetic predispositions and syndromes have been associated with an increased risk of kidney cancer in children. Genetic counseling may be recommended in some families.

4. What is the difference between kidney cancer in children and adults?

   The types of kidney cancer are different. Wilms’ tumor is the most common in children, whereas renal cell carcinoma is the most common in adults. The treatment approaches and prognoses can also differ.