What organ is primarily affected in pediatric patients presenting with Wilms' tumor?

Wilms' tumor, also known as nephroblastoma, is primarily a renal tumor that occurs in children. It originates in the kidney and is one of the most common types of kidney cancer found in pediatric patients. The tumor typically affects one kidney but can sometimes be found in both.

As a developmental tumor, it arises from embryonic renal tissue and generally presents in children between the ages of 2 and 5. Its clinical significance lies in its early detection and the potential for curative treatment, often through a combination of surgery and chemotherapy. This makes the kidney the organ most directly associated with Wilms' tumor and a central focus in both diagnosis and treatment.

Understanding this connection is crucial for healthcare professionals working with pediatric patients, ensuring they recognize symptoms and can initiate appropriate investigations promptly.