Which pediatric renal mass is described as an echogenic malignant solid tumor?

• A. Wilms tumor
• B. Sacrococcygeal teratoma
• C. Omphalocele
• D. Gastroschisis

Answer: (A)

In pediatric imaging, the key idea is identifying the most common malignant renal tumor in children and its typical ultrasound appearance. Wilms tumor is the kidney-originating malignant mass most often described as a solid, sometimes echogenic intrarenal tumor on ultrasound. It tends to be unilateral and can distort the renal contour while usually preserving the capsule early on, and Doppler often shows internal vascularity.

The other options do not fit as renal masses: sacrococcygeal teratoma arises from the coccyx region outside the kidney; omphalocele and gastroschisis are abdominal wall defects with herniation of viscera rather than a renal tumor.