Paediatric Renal Cell Carcinoma: A Rare Entity Evaluated with FDG PET-CT – Diagnostic Insights and Limitations

Renal cell carcinoma (RCC) is extremely rare in the paediatric population. It accounts for only 0.3-1.3% of all paediatric tumours. Amongst renal tumours in the paediatric population, it contributes only a minuscule 2-6%, while Nephroblastoma accounts for 86-87%. These tumours also differ in terms of histology and the mutations that result in their origin based on the age of onset. Here, we present a case of renal cell carcinoma in a 6-year-old girl. She presented with left-sided abdominal pain and a mass on examination. A provisional diagnosis of neuroblastoma was made, considering the clinical presentation- paediatric age group with an abdominal mass. 18 F 2-Fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) was performed. However, the scan showed an irregular renal mass with low-grade FDG avidity and enlarged para-aortic nodes. Total nephrectomy and lymph node excision were performed, and postoperative histopathology confirmed the diagnosis of RCC with nodal metastases. Being rare, paediatric RCC is not well documented, and results from adult studies are applied to paediatric patients in common practice. This case report emphasises the need for more clinical studies regarding the common presentations, patterns of spread and outcomes of RCC in children.