Surgical outcomes with the determining prognostic factors of Wilms Tumors in Oman - A population-based cohort study

Introduction: Wilms tumor (WT) forms 95% of pediatric renal malignancy. Five-year survival rates have dramatically improved and now approach 90 percent. We conducted this research with the specific research question of the recurrence rate, survival rate post treatment and post-surgical complications in WT. Methods: This is a retrospective 10-year study done between January 2010 and August 2022. The study included all patients with WT who underwent treatment in The Royal Hospital, Oman; and had a minimum of one year of follow up. Patients with incomplete hospital records were excluded. Data was retrieved from the hospitals electronic system with ICD code. The retrieved master data sheet was analyzed for patients’ demographics and outcome parameters. Results: Out of the 47 cases, 40 were confirmed cases of Wilms tumor with predominance of males (62.5%). The mean age at presentation was 2.85±1.79 years. Abdominal lump was the most common presentation; Out of the total patients, nine had distant metastasis (most commonly the lungs). There were five recurrences in WT patients and two deaths. There was one case of secondary malignancy (synovial sarcoma). The post-operative complication rate is 17.5%. Conclusion: 5-year Overall Survival was 92.3% (95% CI: 82.1% -102.5%) and 5-year Event (recurrence) Free Survival was 82.1% (95% CI: 68.0% - 96.3%). Post-surgical complications were seen in 17.5% of the patients. There was recurrence in 12.5% of patients. The study provides data for WT in Oman and can be used for reference comparison done in future analysis and in policy making resource distribution and planning of oncology services.