Abstract
Wilms' tumour (nephroblastoma) is the most common abdominal malignancy in children. Extrarenal Wilms' tumour is rare, with limited reports in the literature. We report a two-year-old girl who presented to a tertiary care hospital in Muscat, Oman, in 2019 with an abdominal mass. The patient was diagnosed with unilateral ovarian Wilms' tumour (initially diagnosed by closed biopsy and confirmed later by histopathology study of the excised tumour). This report highlights the unusual location and presentation of Wilms' tumour and presents the medical challenge in both the initial clinical impression and pathological diagnosis. Furthermore, this report details the therapeutic plan and shows the good outcome achieved by using the classic renal Wilms' tumour therapy protocols.