Wilms Tumor (Nephroblastoma) Nursing Care Management

Wilms tumor is a kidney cancer of young children, and the single rule that defines preoperative nursing care is do not palpate the abdomen. Post a sign on the bed. Palpation can rupture the encapsulated tumor and seed cancer cells across the abdomen. Beyond that, your work is supporting the child through nephrectomy, chemotherapy, and radiation, and protecting the one remaining kidney for life.

What is Wilms Tumor?

Wilms tumor (nephroblastoma) is an adenosarcoma in the kidney region. It arises from bits of embryonic tissue that remain after birth, which can spark rapid cancerous growth in the area of the kidney.

Stages

The Children's Oncology Group stages Wilms tumor as follows. Stage 1: the tumor is limited to the kidney and completely resected, the renal capsule is intact, the tumor was not ruptured or biopsied before removal, the renal sinus vessels are uninvolved, and no tumor is present at or beyond the resection margins. Stage 2: the tumor is completely resected with no tumor at or beyond the margins, but it extends beyond the kidney (penetration of the renal capsule, involvement of the renal sinus). Stage 3: residual nonhematogenous tumor remains, confined to the abdomen, including positive abdominal or pelvic lymph nodes, peritoneal penetration or implants, gross or microscopic tumor postoperatively with positive margins, tumor spillage including biopsy, treatment with preoperative chemotherapy, or removal in more than 1 piece. Stage 4: hematogenous metastases (lung, liver, bone, brain) or lymph node metastases beyond the abdomen or pelvis. Stage 5: bilateral renal involvement at diagnosis.

Pathophysiology

Wilms tumor is a malignant mixed tumor containing mesonephric blastoma, stromal, and epithelial derivatives. It involves mutations of the WT1 gene on chromosome 11 and nephroblastomatosis (persistence of renal blastema in kidney tissue). The tumor consists of an epithelial component (abortive tubules and glomeruli) surrounded by metanephric blastema and immature spindle cell stroma; the stroma may include differentiated elements (muscle, cartilage, bone, fat, fibrous tissue) or anaplastic elements. The mass compresses the normal kidney parenchyma.

Statistics and Incidences

Wilms tumor affects approximately 10 children and adolescents per 1 million before age 15 years, accounting for 6-7% of all childhood cancers in North America, where about 450-500 new cases are diagnosed each year. It is relatively more common in Africa and least common in East Asia, and more common in blacks than whites. Estimates are 6-9 cases per million person-years in whites, 3-4 in East Asians, and more than 10 among black populations. Among patients with unilateral Wilms tumor in all NWTSG protocols, the male-to-female ratio was 0.92:1.

Causes

Wilms tumor is thought to result from alterations of genes governing normal genitourinary development. WT1, the first Wilms tumor suppressor gene at chromosomal band 11p13, was identified from studying children with Wilms tumor who also had aniridia, genitourinary anomalies, and mental retardation (WAGR syndrome). A second predisposing gene, not yet cloned, lies telomeric of WT1 at 11p15, proposed from studies of patients with both Wilms tumor and Beckwith-Wiedemann syndrome (BWS), another congenital predisposition syndrome linked to band 11p15.

Clinical Manifestations

The most common presentation is an asymptomatic abdominal mass, found in 80% of children at presentation. Abdominal pain or hematuria occurs in 25%. A few patients with hemorrhage into the tumor present with hypotension, anemia, and fever.

Assessment and Diagnostic Findings

Order a CBC, chemistry profile, urinalysis, coagulation studies, and cytogenetic studies; results may reveal an 11p13 deletion (as in WAGR syndrome) or a duplication of the paternal allele 11p15 (as in BWS). Renal ultrasonography is often the initial study because it spares the child radiation. Abdominal CT helps define the tumor's origin, lymph node involvement, bilateral kidney involvement, invasion of major vessels (such as the inferior vena cava), and liver metastases. Abdominal MRI is reportedly the most sensitive modality for caval patency and helps determine whether the inferior vena cava is directly invaded.

Medical Management

Treatment is surgical removal as soon as possible after discovery, combined with radiation and chemotherapy. For focal anaplastic stage I-III and diffuse anaplastic stage I tumors: nephrectomy followed by vincristine, actinomycin-D, and doxorubicin plus local radiotherapy. For focal anaplastic stage IV and diffuse anaplastic stage II-III tumors: the same plus cyclophosphamide, etoposide, and carboplatin. For stage IV diffuse anaplastic tumors: more aggressive treatment, with nephrectomy followed by initial irinotecan and vincristine, then actinomycin-D, doxorubicin, cyclophosphamide, carboplatin, etoposide, and radiotherapy.

No activity precautions are advised, but the child and parents should know the child will have only 1 kidney after therapy; avoid activities with inherent kidney-injury risk, such as boxing and hockey.

Pharmacologic Management

Several cytotoxic agents can cause liver damage in patients treated for Wilms tumor. Antineoplastic choice depends on stage and histology; commonly used agents include dactinomycin, vincristine, doxorubicin, cyclophosphamide, etoposide, and carboplatin, with dosing based on stage and the child.

Nursing Management

Nursing Assessment

Assess for bleeding from any site and febrile episodes, and monitor WBC, platelet count, hematocrit, and absolute neutrophil count. Assess the oral cavity for pain, ulcers, lesions, gingivitis, mucositis, or stomatitis and its effect on intake. Assess the source and level of anxiety and the need for information and support.

Nursing Diagnoses

Based on the assessment data, major nursing diagnoses include ineffective protection related to antineoplastic agents, radiation therapy, or leukopenia; impaired oral mucous membrane related to chemotherapy; anxiety related to changed health status and threat of death; and risk for injury related to medication side effects and complications.

Nursing Care Planning and Goals

The child will be protected from illness or injury, stay free of oral mucous membrane irritation, experience decreased anxiety, and avoid injury.

Nursing Interventions

To prevent transfer of microorganisms, wash hands before care, use mask and gown when needed, provide a private room, and monitor for signs of infection. To prevent oral trauma, use a soft-sponge toothbrush, toothette, or gauze for rinsing, avoid hot, spicy, or high-ascorbic-acid (vitamin C) foods, provide oral hygiene 30 minutes before or after meals, withhold food and drink for 30 minutes after oral hygiene, and offer moist, soft, bland foods.

To reduce anxiety, keep parents with the child or encourage open visitation, provide a phone number for information, explain all procedures in simple, direct, honest terms and repeat as needed, reinforce physician information, keep nurse assignments consistent, and involve parents in care.

To prevent injury, avoid any palpation of the abdominal mass and post a sign on the bed stating not to palpate preoperatively; assess the incision site for redness, swelling, drainage, intactness, and healing and change the dressing when soiled or wet; assess the oral and perineal area; and have parents dress the child for the weather and avoid rough activities or sports.

Evaluation

Goals are met when the child is protected from illness or injury, stays free of oral mucous membrane irritation, experiences decreased anxiety, and avoids injury.

Documentation Guidelines

Document cultural and religious beliefs and expectations; the plan of care; the teaching plan; responses to interventions and teaching; postoperative care; modifications to the plan; and progress toward desired outcomes.