Very Low and Standard Risk Favorable Histology (FH) Wilms Tumor.
The current COG protocol AREN0532, is a research protocol and designed for patients with very low and standard risk favorable histology (FH) Wilms Tumor.
Patients eligible for this study are:
- Up to 30 years old
- Have Stage I-III FH Wilms tumor
Patients are stratified by clinical and biological risk factors.
Very low risk
Treated with surgery and observation alone:
- Stage I FH Wilms tumor
- Tumor weighs less than 550 g
- Children less than 2 years of age
Standard Risk
Patients given dactinomycin, doxorubicin and vincristine and are NOT given radiation therapy (RT):
- Stage I, FH, Wilms tumors with loss of heterozygosity for 1p and 16q, AND are either age more than 2 years or tumor weight more than 550 g.
- Stage II, FH, Wilms tumor with any weight of tumor or any patient age
Patients given dactinomycin, doxorubicin and vincristine PLUS RT:
- If they have no loss of heterozygosity for 1p and 16q and have Stage III, FH Wilms tumor.
- All Stage I and II patients with spill (including local needle biopsy) are reclassified as stage III based on NWTS 5 data showing inferior relapse free survival (RFS) for Stage II patients (4yr RFS 70% with spill versus 84% without spill).
Aim of study is to achieve the same excellent overall survival from previous studies, while continuing to reduce toxicity.
RT starts at Day 1 for patients whose primary tumors were resected initially. For patients
with delayed tumor resection, RT starts after the primary tumor is resected, usually
at Week 7 or 13.
The indications for RT are:
- Stage III FH Wilms tumor
- Relapsed Stage I FH Wilms tumor (all relapsed patients with pulmonary or intra abdominal tumor bed recurrence).
Indications for RT:
Site |
Indications & RT Dose |
Flank RT |
Stage III - 1080 cGy in 6#
Stage III local tumor spillage 1080 cGy in 6#
Flank or peritoneal biopsy, open biopsy, flank surgical spillage during surgery
Recurrent Wilms tumor - 1080 cGy in 6#
|
Whole Abdomen RT |
Stage III with:
Diffuse unresectable peritoneal implants - whole abdomen dose is - 21 Gy in 150 cGy fractions. Renal shielding needed to limit the dose to the normal kidney to less than 14.4 Gy.
Recurrent intraperitoneal Wilms tumor - 10.5 Gy at 150 cGy per fraction
|
Metachronous Wilms |
|
Lymph Node RT |
|
A boost of 1080 cGy is given to areas of residual tumor after surgery.
Flank RT
Treatment Volumes:
| Radiation Volume | Definition |
Gross Tumor Volume GTV |
|
Clinical Target Volume CTV |
|
Planning Target Volume PTV |
|
- The superior, inferior and lateral borders of RT field are placed at the edge of the PTV.
- The medial border of RT field extends across midline to include entire width of vertebral bodies (with a margin of 1 cm) at level concerned, but not so as to overlap any part of the contralateral kidney.
- RT field should not extend to the dome of the diaphragm unless tumor extends to that height.
- If positive lymph nodes have been surgically removed, then the entire length of the para-aortic chain of lymph nodes should be included in RT field
- An antero-posterior parallel-opposed technique (AP-PA) is recommended for flank RT.
Whole Abdomen RT
The clinical target volume (CTV) is the entire peritoneal cavity
- Extending from the dome of the diaphragm superiorly to the pelvic diaphragm inferiorly, and laterally from the right to the left lateral abdominal wall.
- Femoral heads should be shielded during whole abdominal RT.
- An antero-posterior parallel-opposed technique (AP-PA) is used.
- When the total dose delivered is 2100 cGy ( for diffuse peritoneal implants), renal shielding should be used to limit the dose to the remaining kidney to not more than 1440 cGy.
Extent of fields for Whole Abdominal RT:
Superior limit |
1 cm above the dome of the diaphragm. |
Inferior limit |
at the bottom of the obturator foramen |
Lateral border |
1 cm beyond the lateral abdominal wall. |
