A 2 year old child with Beckwith-Wiedemann syndrome is brought to you with history of an abdominal mass in the right hypochondrium. It was also associated with thrombocytosis and anemia. A CT showed enlarged pulmonary hilar nodes. What is the most probable diagnosis? Note that viral markers are -ve in this patient.

**Core Concept**
Beckwith-Wiedemann syndrome is a congenital overgrowth disorder associated with an increased risk of embryonal tumors, particularly Wilms tumor, hepatoblastoma, and neuroblastoma. The patient's presentation with an abdominal mass, thrombocytosis, anemia, and enlarged pulmonary hilar nodes suggests a malignancy.

**Why the Correct Answer is Right**
The combination of Beckwith-Wiedemann syndrome and the patient's clinical presentation is highly suggestive of Wilms tumor, a type of kidney cancer that primarily affects children. The presence of thrombocytosis and anemia may indicate a paraneoplastic syndrome or bone marrow metastasis. The enlarged pulmonary hilar nodes on CT suggest metastasis to the lungs, which is a common site for Wilms tumor spread.

**Why Each Wrong Option is Incorrect**
**Option A:** Lymphoma is less likely in this scenario, as the patient's presentation and imaging findings do not strongly suggest lymphadenopathy or a lymphoma-like syndrome.
**Option B:** Hepatoblastoma is a possible malignancy in patients with Beckwith-Wiedemann syndrome, but the patient's presentation with an abdominal mass, thrombocytosis, and anemia, combined with enlarged pulmonary hilar nodes, is more suggestive of Wilms tumor.
**Option C:** Neuroblastoma can present with metastatic disease to the lungs, but the patient's thrombocytosis and anemia are not typical findings in neuroblastoma.
**Option D:** Leukemia is unlikely in this scenario, as the patient's presentation with an abdominal mass and thrombocytosis, anemia, and enlarged pulmonary hilar nodes does not suggest a primary bone marrow disorder.

**Clinical Pearl / High-Yield Fact**
Beckwith-Wiedemann syndrome is associated with an increased risk of embryonal tumors, particularly Wilms tumor, hepatoblastoma, and neuroblastoma. The presence of an abdominal mass, thrombocytosis, anemia, and enlarged pulmonary hilar nodes in a child with Beckwith-Wiedemann syndrome should raise suspicion for Wilms tumor.

**Correct Answer:** B.

✓ Correct Answer: C. Hepatoblastoma