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Evaluation of renal tumors in children.

OBJECTIVE
Renal tumors are not uncommon in children. In this study, we aimed to evaluate the clinical and pathological features of renal tumors in children.


MATERIAL AND METHODS
Between January 2008 and December 2017, the records of children with renal tumors in our institution were retrospectively analyzed. Data collected were composed of demographic and clinical characteristics including gender, age at time of diagnosis, symptoms, laterality of the tumor and pathological evaluation.


RESULTS
A total of 48 children with renal tumor (28 males and 20 females) were included in the study. They were diagnosed at mean age of 53.26±46.64 months (range: 1-192) and the mean follow-up period was 73.45±48.92 months (range: 6-120). The most common symptom was a lump or mass in the area of the kidneys (45.8%), abdominal pain and hematuria (14.6%). Four patients (8.3%) were diagnosed at antenatal period. 68.8% of the children had Wilms tumor and the major histological groups of non-Wilms renal tumors were renal cell carcinoma (12.5%), congenital mesoblastic nephroma (10.4%) and angiomyolipoma (4.2%). 10.4% of the children had bilateral tumors and one patients had Wilms tumor with horseshoe kidney. 87.5% of the children were treated with surgery and of those 7 (14.5%) underwent nephron-sparing surgery. The patients had chemotherapy and radiotherapy (83.3% and 41.7%, respectively). Seven patients (14.6%) died during follow-up.


CONCLUSION
Wilms tumor is the most common pediatric renal neoplasm. On the other hand, we showed that considerable number of children with renal tumors had non-Wilms tumors including renal cell carcinoma, congenital mesoblastic nephroma and angiomyolipoma.