Question
Which of the following statements regarding nephroblastoma (Wilms tumor) is false?
| A. |
Treatment according to the SIOP protocol consists of neoadjuvant chemotherapy followed by nephrectomy.
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| B. |
Pulmonary metastases are present in the majority of patients at the time of diagnosis.
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| C. |
Wilms tumor spreads predominantly by the hematogenous route.
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| D. |
The lungs are the most common site of distant metastasis.
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Show Answer
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Correct Answer » B
Explanation
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Wilms tumor (nephroblastoma) is the most common malignant renal tumor in children. It usually presents as a painless abdominal mass and is confined to the kidney at diagnosis. Although it commonly spreads to the lungs, distant metastases are present in only a minority of patients at initial presentation.
Explanation of the Correct Answer
B. Pulmonary metastases are present in the majority of patients at the time of diagnosis.
- This statement is false.
- Only 10–15% of children have lung metastases at the time of diagnosis.
- Most patients present with localized disease (Stage I–III).
- Pulmonary metastases indicate Stage IV disease.
Why the Other Options are Correct
A. Treatment according to the SIOP protocol consists of neoadjuvant chemotherapy followed by nephrectomy.
- Correct.
- The SIOP protocol recommends:
- Preoperative chemotherapy.
- Radical nephrectomy.
- Postoperative chemotherapy ± radiotherapy depending on stage and histology.
C. Wilms tumor spreads predominantly by the hematogenous route.
- Correct.
- Hematogenous spread is the principal route of dissemination.
- Common metastatic sites include:
- Lungs (most common)
- Liver
- Bone (rare)
D. The lungs are the most common site of distant metastasis.
- Correct.
- The lungs are the commonest site of distant metastatic spread in Wilms tumor.
