Adult-Onset Wilms Tumor: A Case Report

Background: Wilms tumor or nephroblastoma is the most common pediatric renal malignancy. However, the presentation of the adult variant of this tumor is rare, especially in our low-resource setting where there is a diagnostic challenge. This tumor is often missed, resulting in a poorer prognosis than that associated with the childhood variants. We present the case of a young adult with a Wilms tumor who was initially diagnosed with renal cell carcinoma. Case presentation: This is the case of an eighteen-year-old boy who presented with a prolonged history of progressive painful left flank fullness, hematuria, low-grade fever, nausea/vomiting, and weight loss in whom examination also revealed hypertension, a tender left flank mass, and left varicocele. Abdominal/chest CT suggested a malignant tumor in the left kidney with inferior vena cava thrombosis, para-aortic lymph node involvement, and lung metastasis presumed to be renal cell carcinoma. Following radical left nephrectomy and histopathological examination, a final diagnosis of stage IV left blastemal-type Wilms tumor was made. The patient was discharged on postoperative day nine and referred for adjuvant chemotherapy and localized radiotherapy to the lung and left flank area. However, he died several weeks after surgery without adjuvant therapy after being lost to follow-up. Conclusion: This report aims to alert clinicians of adult-onset Wilms tumor when an adult presents with a flank mass especially as this is a rare condition. This should allow for early diagnosis and expeditious management of this disease variant.