Treatment

Screening

Screening is reserved for children at risk for developing WT. This includes children with genetic syndromes such as Beckwith-Wiedemann syndrome (BWS), idiopathic hemihypertrophy (IHH), WAGR, dopamine dysregulation syndrome (DDS), and Perlman syndrome. Renal ultrasound examination is the preferred modality to screen for WT. It is widely available, noninvasive, does not involve radiation exposure, and generally does not require use of sedation. It is recommended that children be scanned every 3 to 4 months.

The main types of treatment that can be used for Wilms tumor are:

* Surgery

* Chemotherapy

* Radiation therapy

 

Most children will get more than one type of treatment.

Treatment for WT is based mainly on the stage of the cancer and whether its histology. In the United States, doctors prefer to use surgery as the first treatment in most cases, and then give chemotherapy (and possibly radiation therapy) afterward. In Europe, doctors prefer to start the chemotherapy before surgery. The results seem to be about the same.

Surgical therapy is a primary component in the multidisciplinary treatment of WT or other neoplastic renal lesions. Irrespective of whether surgery is performed as a primary therapy or in a delayed fashion after chemotherapy, there are a number of fundamental tasks that are required of the surgeon. These are (1) safe resection of the tumor, (2) accurate staging of the tumor, (3) avoidance of complications that will "upstage the tumor" (rupture or unnecessary biopsy), and (4) accurate documentation of operative findings and details of the procedure in the operative note. Intraoperative events that negatively affect patient survival include tumor spill, failure to biopsy lymph nodes, incomplete tumor removal, failure to assess for extrarenal tumor extension and surgical complications.

The abdomen is explored through a generous transverse, upper abdominal incision. The presence of bloody ascites suggests tumor rupture and Stage III disease. This fluid should be sent for cytology. Before the tumor is removed, the contralateral kidney is manually and visually inspected. Any and all suspicious lesions are biopsied. If the contralateral kidney is normal, an ipsilateral radical nephroureterectomy is performed with care taken not to rupture the tumor. Periaortic lymph nodes are sampled and titanium clips are placed along the margins of resection. If there is bilateral disease and wedge/partial resection of all tumors will result in removal of greater than one-third of the total renal mass, biopsy is done and the operative area is closed. Afterward, the child is treated with chemotherapy and re-explored in 6 weeks.

All children with WT receive postoperative chemotherapy. Those with Stage I and II lesions and favorable histology are treated with actinomycin D and vincristine. Children with Stage III and IV lesions and favorable histology and children with Stage II or III disease and focal anaplasia are treated with actinomycin-D, vincristine and adriamycin (doxorubicin) and postoperative abdominal irradiation. Children with Stage II, III and IV lesions and diffuse anaplasia and those with Stages I to IV with clear cell sarcoma are treated with four drugs (cyclophosphamide, doxorubicin, vincristine and etoposide) and postoperative irradiation with 1080 cGy.

Indications for postoperative radiation therapy include gross residual tumor, tumor spill, positive lymph nodes, peritoneal involvement, Stage IV disease and unfavorable histology. Indications for preoperative chemotherapy include Stage V disease, IVC involvement above the hepatic veins, massive tumor and cytoreductive therapy if other organs are at risk.

Children with congenital mesoblastic nephroma do not require adjuvant therapy.

Recurrent Wilms` tumor

The prognosis and treatment for children with WT that recurs (comes back after treatment) depends on their prior treatment, the cancer’s histology (favorable or unfavorable), and where it recurs. The outlook is generally better for recurrent Wilms tumors with the following features:

§ Favorable histology

§ Initial stage of I or II

§ Initial chemo with vincristine and actinomycin D only

§ No previous radiation therapy

The usual treatment for these children is surgery to remove the recurrent cancer (if possible), radiation therapy (if not already given to the area), and chemo, often with different drugs than those used during first treatment.

 

Recurrent WT that do not have the features listed above are much harder to treat. These children are usually treated with aggressive chemo, such as the ICE regimen (ifosfamide, carboplatin, and etoposide) or others being studied in clinical trials. Very high-dose chemo followed by a stem cell transplant (sometimes called a bone marrow transplant) might also be an option in this situation.