Delayed tumor resection in a 5-year-old child with bilateral Wilms tumor

Samuel P. Carmichael,1 Joseph F. Pulliam,2 and John A. D'Orazio3,*

Abstract

We describe the case of a 5-year-old girl whose abdominal pain and distension were caused by Wilms tumor of the kidney. Because of the bilateral nature of her disease, she was spared biopsy or initial nephrectomy as part of her treatment course. Rather, she was treated presumptively for Wilms tumor based primarily on radiologic findings. Neoadjuvant chemotherapy consisting of vincristine, dactinomycin and doxorubicin was given to facilitate nephron-sparing surgery for tumor resection. Her initial chemotherapeutic course was complicated by tumor lysis syndrome manifested by elevated serum uric acid and was treated effectively with hyperhydration and alkalization of intravenous fluids. The patient's disease responded well to chemotherapy, and she underwent successful tumor excision after 12 weeks of chemotherapy. The resected tumor was identified as anaplastic Wilms tumor, illustrating that pathologic identification of Wilms tumor is possible even after multiple cycles of neoadjuvant chemotherapy and marked tumor shrinkage.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3635223/

Hyperuricemia may occur because of decreased excretion (underexcretors), increased production (overproducers), or a combination of these two mechanisms. My  opinion it is due to cytotoxic therapy.

It is very important rehydration with allopurinol, Hyperuricemia may occur because of decreased excretion .

LYSIS OF THE TUMOR CELLS, BECAUSE CHEMOTHERAPY OR CELL DEATH ITSELF

Hyperuricemia in this case might be due both to an increased cell lysis- of probably normal cells due to the chemotherapy the child gets along with a reduced excretory capacity of the remaining kidney. Renal function should be thoroughly assessed as well as possible involvement of the second kidney with another Wilms tumor- which might be the case for so young kids presenting with Wilms tumor before 1 year of age.