Wilms tumor

Wilms Tumor - Childhood

About Kidneys

The kidneys are two vital organs that filter blood, remove waste products, excess minerals, salts, and water from the body, and produce essential hormones. These hormones help regulate blood pressure and the production of red blood cells.

During fetal development, kidney cells differentiate into:

• Glomeruli: Filter water, salts, and waste from the blood.

• Nephrons: Tubes that carry filtered water and waste

‍

What is Wilms Tumor?

Wilms tumor, also known as nephroblastoma, occurs when immature kidney cells fail to develop into glomeruli or nephrons during fetal growth. Normally, these cells mature by the time the child is 3-4 years old, but if they continue to grow uncontrollably, they form a malignant tumor.

• Wilms tumor is the most common kidney cancer in children.

• It typically affects one kidney, but in rare cases, it can develop in both kidneys.

• The tumor is usually detected when the kidney enlarges up to four times its normal size.

• In about 25% of cases, the tumor spreads to the lungs or liver before diagnosis.

Statistics

• In the United States, 500 to 600 children are diagnosed with Wilms tumor annually.

• It accounts for 4% of all childhood cancers.

Survival Rate

• The 5-year survival rate for Wilms tumor is 93%.

Risk Factors

Several factors increase the risk of Wilms tumor:

• Genetic Mutations: Changes or damage to certain genes in children.

• WAGR Syndrome: Children with Wilms tumor, Aniridia (absence of iris), Genitourinary abnormalities, and Intellectual disabilities have a 33% chance of developing Wilms tumor.

• Beckwith-Wiedemann Syndrome: A disorder affecting organ and limb growth, increasing the risk of Wilms tumor.

• Denys-Drash Syndrome: A condition affecting the development of male reproductive organs and increasing the risk of Wilms tumor.

• Family History: In some cases, the tumor may run in families.

Symptoms

• Blood in urine (Hematuria)

• High blood pressure

• Abdominal swelling or pain

• Fatigue

• Persistent fever

Diagnosis

• Urine Test

• Blood Test

• X-ray, Ultrasound, CT Scan, or MRI

• Bone Scan (to check for spread to bones)

• Surgery/Biopsy:

• In Stage I or II, surgery (radical nephrectomy) is performed to remove the affected kidney.

• If the tumor is large, a biopsy is done before surgery.

• For tumors in both kidneys, biopsy and chemotherapy are done first, followed by surgery.

• Chromosome Test:

• Checks for changes in chromosome 1 or chromosome 16.

• Tumors with these mutations may not respond well to treatment.

Stages of Wilms Tumor

1. Stage I:

• The tumor is confined to one kidney and can be fully removed through surgery.

2. Stage II:

• The cancer has spread to nearby tissues or blood vessels but can still be removed surgically.

3. Stage III:

• The tumor has spread to nearby organs and lymph nodes but not beyond the abdomen. Surgery is challenging at this stage.

4. Stage IV:

• The cancer has spread to distant organs, such as the lungs or liver.

5. Stage V:

• Tumors are present in both kidneys, and each kidney is staged separately.

6. Recurrent:

• The cancer returns after treatment.

7. Refractory:

• The tumor does not shrink even after treatment.

Treatment Options

1. Surgery

• Surgery is the primary treatment for Wilms tumor.

• Types of Surgery:

• Radical Nephrectomy: Removes the affected kidney, surrounding tissues, and nearby lymph nodes.

• Partial Nephrectomy: Removes only the tumor and a portion of the kidney, preserving kidney function (used when both kidneys are affected).

• If both kidneys are removed or become dysfunctional, dialysis is required.

2. Chemotherapy

• Uses drugs to destroy cancer cells.

• Neoadjuvant Chemotherapy: Given before surgery to shrink the tumor.

• Adjuvant Chemotherapy: Given after surgery to destroy remaining cancer cells.

• Common Chemotherapy Drugs:

• Dactinomycin (Cosmegen)

• Vincristine (Oncovin)

• Doxorubicin (Adriamycin)

• Cyclophosphamide (Cytoxan)

• Etoposide (Toposar)

• Irinotecan (Camptosar)

• Side Effects: Fatigue, nausea, vomiting, infections, hair loss, appetite loss, and diarrhea. Side effects usually diminish after treatment.

3. Radiation Therapy

• Uses high-energy radiation to destroy cancer cells.

• External Beam Radiation Therapy (EBRT) is used for tumors that are large or have spread beyond the kidney.

• Radiation is typically used for Stage III or IV tumors.

• Side Effects: Skin redness, itching, fatigue, and diarrhea. These effects subside after treatment.

Follow-Up Care

After treatment, regular follow-ups are essential to monitor for cancer recurrence and manage side effects. Follow-up care includes:

• Physical exams

• Blood tests

• Imaging tests such as CT or MRI

Wilms tumor is a rare but treatable childhood cancer. Early detection and treatment can lead to successful outcomes, with a high survival rate. Ongoing follow-up is crucial to ensure long-term health and well-being.

‍