Wilms tumor is a rare type of kidney cancer that is commonly diagnosed in children. It accounts for about 6-7% of childhood cancers. There are different types of Wilms tumors based on their aggressiveness and the cell type that they arise from.
Gaining an understanding of the crucial aspects of Wilms tumor, such as its types, stages, risk factors, and treatment options, will support informed decision-making among patients and help them lead a healthy life.
Wilms tumor, also known as nephroblastoma, Wilms cancer, or Wilms nephroblastoma, is a rare form of kidney cancer that primarily affects children.
Nephroblastoma usually arises from immature kidney cells. The immature cells present during the early development of the fetus are destined to mature and develop into the glomeruli and nephrons, which are responsible for filtration. When these cells fail to mature, they can form clumps at birth. By age 3 or 4, these clumps might begin to grow uncontrollably to form Wilms tumor.
Wilms tumor, or Wilms cancer, is one of the most common types of kidney cancer in children. It represents approximately 6-7% of all childhood cancers. The incidence is higher in certain age groups, peaking between 3 and 4 years old. Although relatively rare, the recognition of Wilms nephroblastoma is vital due to the potential for successful treatment and positive outcomes.
There are different types of Wilms tumor depending on the cell type from which they arise. Certain types of Wilms have a better prognosis than others. Based on the histology, the following are the different types of Wilms tumor:
This is the more common and less aggressive form of Wilms tumor. The cells in favorable histology tumors appear normal under the microscope, and the prognosis is generally favorable with appropriate treatment.
This is also referred to as an unfavorable Wilms tumor. Anaplastic histology represents a more aggressive subtype of Wilms cancer. The cells in these tumors exhibit abnormal features under the microscope, and treatment approaches may need to be more intensive to address the increased risk.
While Wilms tumor is the predominant kidney cancer in children, other types include:
A rare tumor occurring in early infancy, mesoblastic nephroma is usually benign but can occasionally be malignant.
Clear cell sarcoma of the kidney is a rare and aggressive kidney cancer that typically affects children.
This is a rare and aggressive tumor that occurs in young children. It is characterized by the loss of a specific gene, resulting in rapid tumor growth.
While more common in adults, renal cell carcinoma can occur in children. It is distinct from Wilms tumor in terms of its biology and treatment approach.
Childhood kidney cancer, or Wilms tumor, is classified into stages to determine the extent of its spread. Wilms tumor staging helps guide treatment decisions and predict prognosis. The stages range from localized tumors confined to the kidney to more advanced cases with widespread involvement. The following are the different stages of Wilms cancer:
In this initial stage, the tumor is limited to the kidney and can often be completely removed through surgery. The prognosis for Stage 1 Wilms tumor is generally favorable, with high chances of successful treatment.
Stage 2 involves a nephroblastoma that extends beyond the kidney but is still completely removable by surgery. Despite the tumor's extension, the prognosis remains favorable, and treatment success is achievable with comprehensive therapeutic approaches.
At this stage, the tumor has spread beyond the kidney and may involve nearby structures or lymph nodes.
Stage 4 signifies a more advanced stage where the tumor has spread to distant organs or lymph nodes. Treatment for stage 4 Wilms tumor demands a comprehensive treatment approach to target both the primary tumor and distant metastases.
The final stage, stage 5, indicates bilateral involvement, where tumors are present in both kidneys. Managing stage 5 Wilms tumor is complex, requiring a multidisciplinary approach to address tumors in both kidneys and any potential spread.
Understanding the stages of nephroblastoma is crucial for tailoring effective treatment plans. Prognosis varies based on the extent of tumor spread, with early-stage tumors often having more favorable outcomes. A collaborative effort between patients, uro-oncologists, pediatric oncologists, and families is essential for navigating the challenges associated with each stage and achieving the best possible outcome for children diagnosed with Wilms cancer.