Purpose: A reference radiologic diagnosis was carried out for the purpose of quality control and in order to achieve high diagnostic accuracy in the ongoing trial and study SIOP 2001/GPOH for renal tumors during childhood. The aim of the present study is to evaluate the value of diagnostic imaging and the benefit of reference evaluation at a pediatric radiology center.
Materials and methods: In 2004 the imaging studies of 97 patients suspected of having a renal tumor were presented at the beginning of therapy. Diagnostic imaging was compared to the primary imaging results and the histological findings and was analyzed in regard to the therapeutic consequence (primary chemotherapy without prior histology). 77 MRI, 35 CT and 67 ultrasound examinations of 47 girls and 50 boys (mean age 4 years; one day to 15.87 years old) were analyzed. In addition to the histological findings, the reference pathological results were submitted in 86 cases. Results from the primary imaging corresponding to the histology and results from the reference radiology corresponding to the histology were statistically compared in a binomial test.
Results: In 76 of the reference-diagnosed Wilms' tumors, 67 were confirmed histologically. In 72 cases preoperative chemotherapy was initiated. In 5 cases neither a Wilms' tumor nor a nephroblastomatosis was found. 16 of 21 cases (76 %) with reference-diagnosed non-Wilms' tumors were selected correctly. The results of the primary imaging corresponded to the histology in 71 cases, and those of the reference radiology in 82 cases. The statistical evaluation showed that the results of the reference radiology were significantly better (p = 0.03971).
Conclusion: Reference radiological evaluation improved the diagnostic accuracy with therapeutic relevance. The differentiation of different renal tumors is not completely possible using imaging methods. The rate of patients with false preoperative chemotherapy for all renal neoplasms is currently 5.2 % and 1 % for benign renal tumors.