Prognostic Impact of HER/2 Expression on Survival of Preoperatively Treated Children with Wilms Tumor at South Egypt

Abstract

Aim: Wilms tumor (WT) is the most frequent type of pediatric renal tumors. Her/2 is an oncoprotein, its over-expression revealed to play a very vital role in the progress and improvement of certain tumors. This study evaluates the possible role of Her/2 as a prognostic indicator in formerly treated WT. Method: Immunohistochemical expression of Her/2 was studied in paraffin material of 40 WT patients followed SIOP 9 protocol. Patients' medical records reviewed for clinical, pathological and outcome data and correlated with HER2 expression. Additional 15 samples of normal surrounding kidney tissue specimens were included. Results: Her/2 was often expressed in normal kidney tissue (renal tubules but not glomeruli) and at variable levels in the three elements of WT. At a median of 84 months, 70% of patients are living and under follow-up, surgical stage and pathologic subtypes were the only two factors significantly affect the outcome of our patients (p = 0.000, p = 0.007 & p = 0.004, p = 0.005 for OS (Overall survival) and DFS (Disease Free survival) respectively). Her/2 expression was associated with epithelial differentiation (p < 0.001). There was non-significant effect of Her/2 expression on OS or DFS of studied group. Conclusion: while the major progress in studying biology of WT, stage and pathological subtype continues the only predictive factors of significant value affecting the outcome of patients with WT. There was important association between Her/2 expression and histological differentiation in formerly treated Wilms tumor. Non-conclusive results regarding influence of Her/2 expression on the result of WT patients were found.