Wilms tumor treatment

Treatment of Wilms tumor involves a multimodal approach, including surgery, chemotherapy, and radiation therapy. All patients undergo nephrectomy and cytostatic therapy. The optimal sequence of surgery and chemotherapy remains controversial. Radiation therapy is administered in an adjuvant setting, with a high prevalence of the tumor process, as well as in the presence of unfavorable factors for disease progression. Treatment of Wilms tumor is determined based on the stage of the disease and tumor anaplasia.

In North America, the standard approach to treating Wilms tumor is immediate nephrectomy followed by chemotherapy with or without postoperative radiation therapy.

Treatment of Wilms tumor depending on the stage and histological structure of the tumor

Tumor stage	Histology	Operation	Chemotherapy	Radiation therapy
I, II	Favorable	Nephrectomy	Vincristine, dactinomycin (18 weeks)	No
I	Anaplasia
III, IV	Favorable	Nephrectomy	Vincristine, dactinomycin, doxorubicin (24 weeks)	Yes
II, III, IV	Focal anaplasia
II, III, IV	Diffuse anaplasia	Nephrectomy	Vincristine, doxorubicin, cyclophosphamide, etoposide (24 months)	Yes

* Total focal doses: to the bed of the removed kidney - 10.8 Gy; to all lungs in patients with lung metastases - 12 Gy.

In Europe, patients with Wilms tumor receive preoperative chemotherapy with vincristine and dactinomycin, followed by nephrectomy and postoperative treatment, the regimen of which at different stages of the disease does not differ significantly from the North American standards given above. The European protocol for the treatment of Wilms tumor involves the use of higher doses of radiation (15-30 Gy).

Chemotherapy used for Wilms tumor is based on regimens that include dactinomycin, vincristine and doxorubicin as first-line therapy and cyclophosphamide, etoposide - as salvage treatment for Wilms tumor in case of tumor recurrence or in patients with a poor prognosis group. Doses of antitumor drugs depend on the stage and the child's body surface area.

Estimated doses of antitumor drugs used in Wilms tumor

Stage	Preparation	Dose
I	Dactinomycin	1000 mcg/ m2
	Vincristine	1.5 mg/ m2
II	Dactinomycin	1000 mcg/ m2
	Vincristine	1.5 mg/ m2
	Doxorubicin	40mg/ m2
	Cyclophosphamide	100 mg/ m2
	Etoposide	400 mg/ m2
III	Dactinomycin	1.2 mg/ m2 (not more than 2 mg)
	Vincristine	1.5 mg/ m2
	Doxorubicin	50 mg/ m2
	Cyclophosphamide	600 mg/ m2
	Etoposide	100 mg/ m2
IV	Dactinomycin	1.2 mg/ m2 (not more than 2 mg)
	Vincristine	1.5 mg/ m2
	Doxorubicin	50 mg/ m2
	Cyclophosphamide	600 mg/ m2
	Etoposide	100 mg/ m2

Further management

In order to promptly detect and adequately treat Wilms' tumor and tumor recurrence, all patients undergo careful dynamic monitoring, the frequency and type of which are determined by the stage and histological structure of the tumor.

Dynamic observation tactics for patients with Wilms tumor

Stage and histological structure	Type of examination	Mode
All patients	Chest X-ray	6 weeks and 3 months after surgery, then every 3 months (5 times), every 6 months (3 times), annually (2 times)
Stages 1 and II, favorable histology	Ultrasound of the abdominal cavity and retroperitoneal space	Annually (6 times)
Stage III, favorable histology	Ultrasound of the abdominal cavity and retroperitoneal space	6 weeks and 3 months after surgery. Then every 3 months (5 times). Every 6 months (3 times), annually 12 times)
All stages, unfavorable histological structure	Ultrasound of the abdominal cavity and retroperitoneal space	Every 3 months (4 times), then every 6 months (4 times)

Wilms tumor prognosis

The prognosis for children with Wilms tumor is favorable. Three-modal treatment of Wilms tumor leads to recovery of 80-90% of patients.

With a favorable histological variant of the tumor, the overall and relapse-free four-year survival rates of patients with stage I are 98 and 92%, stage II - 96 and 85%, stage III - 95 and 90%, stage IV - 90 and 80%, respectively.

Patients with synchronous bilateral tumors have a remote survival rate of 70-80%, metachronous 45-50%. Wilms tumor with relapses has a moderate prognosis (overall survival 30-40%).