Comparison of the Clinical Presentation of Two Age Groups in Pediatric Wilm's Tumor Patients at a Single Institution

BACKGROUND: The long term survival rates for Wilm's Tumor in North America and Europe have increased to almost 85% overall. There is an emphasis on "risk based management" where children who are diagnosed with low stage tumors can achieve excellent outcomes with less intensive chemotherapy and radiation. This study aims to characterize difference of the presentation of Wilm's Tumor patients between a younger and an older age group at Children's Medical Center over 5 years from 2010 to 2015. METHODS: A retrospective review of 35 children presenting with Wilm's Tumor at Children's Medical Center of Dallas between April 2010 and April 2015 was conducted and data was collected on demographics, associated symptoms, stage of tumor, tumor histology, and outcome data. These data points were stratified between two age groups, either younger or older than 3 years old (yo). RESULTS: Ages at time of surgery ranged from ages 7 months to 15 yo, with a median age of 3 yo. Of the 16 patients younger than 3 yo, there were 10 males and 6 females, 7 white and 9 non-white, and 7 left-sided and 7 right-sided. Only 3 patients presented with abdominal pain, while 13 presented with an asymptomatic mass. Seven patients had stage 1 /2 tumors, and 9 patients had stage 3/ 4 tumors. Three of the patients had lung metastases while 12 were non metastatic tumors limited to the kidney. Of the 19 patients older than 3 yo, there were 6 males and 13 females, 14 white and 5 non-white, Sixteen patients presented with abdominal pain at the time of diagnosis while only 3 had an asymptomatic mass. There were 16 were left sided and 3 right sided tumors, 4 patients with stage 1/2 tumors and 15 patients with stage 3/4 tumors. Twelve patients had lung metastases at the time of surgery while 7 were non-metastatic tumors limited to the kidney. Compared to patients younger than 3 yo at time of surgery, patients older than 3 yo were more likely to present as female (p= 0.0946) and white (p= 0.094 ). They were also more likely to have left-sided tumor laterality (p= 0.057), have abdominal pain (p= 0.0002), and have lung metastases at time of surgery (p= 0.02). CONCLUSION: Despite a small study population from a single institution, these data demonstrate significant and critical differences in presentation, anatomy and severity of Wilm's tumor based on age at presentation.