Prognosis for FH Wilms tumor patients is good with at least a 90% cure rate for localized disease and over 70% for metastatic disease with conventional treatment modalities. The overall survival rate of patients is rising steadily mostly due to collaborative trials.
Factors predictive of outcome include:
- Histology (favourable histology vs anaplastic)
- Stage
- Gene expression profile (e.g. 1q gain; LOH 1p and 16q)
- Age (Older age is associated with adverse prognosis)
- Tumor size
Relapse free survival of children diagnosed at a younger age in both unilateral and bilateral disease is better than older children. There is a weak correlation between increasing tumor size and adverse prognosis.
Very low risk disease
- Have a combination of factors above
- Stage I FH Wilms tumor
- Tumor weighs less than 550 g
- Patient less than 2 years old
- Excellent prognosis
- Can be treated with surgery alone
Gene expression profile
- 1q gain is associated with adverse outcome. An association between 1q gain and loss of chromosomes 1p and 16q has been noted - indicating that the prognostic significance of LOH at 1p and 16q may not be independent of 1q gain.
- Future studies will likely incorporate 1q gain into the risk stratification schema.
Tumor-specific Loss of Heterozygosity (LOH) for specific chromosomes is a prognostic factor in Wilms tumor.
- Tumor-specific LOH for either chromosome 1p or 16q is associated with a worse
outcome in FH Wilms tumors, relative to those without LOH. - LOH for chromosome 1p seen in about 11% of Wilms tumors and is associated with poorer outcome . Tumor-specific LOH 1p is associated with a significantly worse outcome for Stage II patients but not for Stage III/IV (more intense chemotherapy in latter group overcomes negative effect of LOH 1p).
- Tumor-specific loss of 16q in 20% of patients and associated with a poorer two-year
Relapse Free survival (RFS). - LOH for chromosome for both 1p and 16q in Stage I and II FH Wilms tumor is associated with a poorer prognosis with a greater risk of relapse and mortality.
- Stage I or II FH tumors with either LOH 1p or LOH 16 q alone have a lesser risk for relapse than those with both LOH 1p and 16q.
Histology
The unfavorable pathology types make up a very small proportion of renal tumors in children, but account for most deaths.
Patients with unfavourable histology Wilms tumor have a much worse prognosis than those with FH.
