Wilms Tumor

What is Wilms tumor?

Wilms tumor (also called nephroblastoma) is a cancerous tumor in the cells of the kidney. Fortunately, with the right treatment, it is highly treatable. 

It is the most common type of renal (kidney) cancer in children, accounting for about 6 percent of all childhood cancers. About 500 children in the U.S. are diagnosed with a Wilms tumor each year. It can occur at any age between infancy and age 15 but is most common in children age 5 or younger. Adults rarely have Wilms tumor.

The tumor can spread outside the kidney, most often to the abdominal lymph nodes and lungs. With prompt and aggressive treatment, Wilms tumor is successfully treated in the majority of children. Multidisciplinary approaches, including a combination of surgery and/or chemotherapy and/or radiation therapy can be used.

How we care for Wilms tumor

Children with Wilms tumor receive highly coordinated multidisciplinary care through the Kidney Tumor Program at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center.

As a regional, national, and international referral center, our surgeons and solid tumor oncologists have extensive expertise in the care of children with Wilms tumor, particularly those with bilateral tumors (tumors on both sides of the abdomen), large tumors, or "unfavorable" tumor subtypes rarely seen elsewhere. Our multidisciplinary team, which draws on specialists from across Dana-Farber Cancer Institute and Boston Children's Hospital, works together to develop thoughtful and precise treatment plans.

Wilms tumor specialists at Dana-Farber/Boston Children’s have pioneered important new surgical and medical approaches to the treatment of Wilms. They also play key roles in large cooperative studies through the National Wilms Tumor Study Group and Children's Oncology Group. These studies have rigorously compared treatment plans to determine the most effective and safest treatments and have helped to greatly advance Wilms tumor treatment over the last three decades.

Our areas of research for Wilms tumor

Researchers at Dana-Farber/Boston Children’s Kidney Tumor Program conduct laboratory and clinical research designed to improve understanding and treatment of pediatric kidney tumors. We also offer clinical trials through the Children’s Oncology Group (COG).

Identifying the best treatment for Wilms tumor

Major advancements have occurred in the treatment of Wilms tumor over the last three decades, primarily because of studies by the National Wilms Tumor Study Group and Children's Oncology Group, in which Dana-Farber/Boston Children’s physicians have played key roles. These studies have rigorously compared treatment regimens (treatment plans) and helped define the optimal treatment for each stage and type of Wilms tumor. In one large study, it was shown for low-stage Wilms tumor that briefer courses of therapy were safer and as effective as longer courses. A recent COG study initiated by Dana-Farber/Boston Children’s doctors, including Robert Shamberger, MD, and Elizabeth Mullen, MD, FAAP, demonstrated that young children (less than two years of age) with small tumors can be treated safely with surgery only, without the need for chemotherapy or radiation. This study also offered adjustments of therapy for children with Stage I, II, and III tumors based on specific genetic findings. This study is the first study in childhood renal tumors to base therapy on the biology of the individual child’s tumor. Elizabeth Mullen, MD, FAAP, is the vice-chair of this study. 

Renal tumor biology and risk stratification

Elizabeth Mullen, MD, FAAP, is the Protocol Chair for the COG Renal Tumor Biology and Risk Stratification Protocol (AREN03B2). This has been open since 2006, remains open to accrual, and currently has enrolled over 4,800 patients. This study involves real-time, coordinated review of Wilms tumor diagnoses by multiple specialists to determine the most accurate staging and risk stratification. Through this study, researchers have learned that many cases of Wilms tumor are initially misdiagnosed or not accurately staged. Through accurate diagnosis and staging, however, children can receive the best possible treatment regimen.

Risk-stratifying treatment of children with bilateral tumors

The traditional treatment for pediatric kidney tumors is a two-step process: Surgeons remove as much of the tumor as possible, then oncologists use chemotherapy to kill remaining cancerous cells. If the tumor is bilateral (appearing in both kidneys), chemotherapy is sometimes also used before surgery to reduce the size of the tumor so as to save the maximum amount of healthy kidney tissue. Our researchers are investigating the use of continuous pathological review throughout treatment to evaluate the best therapeutic approach for bilateral pediatric kidney tumors.

Searching for markers

Researchers are conducting studies to better understand how to diagnose and treat renal tumors. For example, our researchers are investigating whether kidney tumors emit markers in a child’s urine. If discovered, these markers could be used to screen for early recurrence of relapsed cancers. They may also help clinicians screen types of tumors up front, so treatments are personalized to the exact make-up of a child’s tumor. Dana-Farber/Boston Children’s is also involved in one of the country’s most comprehensive precision cancer medicine initiatives, called Profile. Ultimately, this important research project will result in a database of genetic changes in all types of cancer, including Wilms tumor. This research is advancing scientists’ understanding of the genetic causes of cancer and how that information may ultimately lead to improved treatment.

For many children with rare or hard-to-treat conditions, clinical trials provide new options.