Commonest site of metastasis of Wilm’s tumour is ?
**Core Concept**
The question tests the understanding of the metastatic pattern of **Wilm's tumor**, a type of **nephroblastoma** that primarily affects children. **Hematogenous spread** is a common mode of metastasis for this tumor. Knowledge of **oncology** and **pediatric surgery** is essential.
**Why the Correct Answer is Right**
Although the specific options are not provided, typically, the commonest site of metastasis for Wilm's tumor is the **lungs**, due to the tumor's tendency to spread through the **hematogenous route**. The **pulmonary capillaries** are a first-pass capillary bed for blood draining from the **inferior vena cava**, where tumor cells from the kidney can easily lodge and grow.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option, it's hard to comment, but if it were **liver**, it would be incorrect because, while the liver can be a site of metastasis, it's not the most common for Wilm's tumor.
**Option B:** Similarly, without the option, if we consider **bone**, it's not the most frequent site of metastasis for Wilm's tumor.
**Option D:** If **brain** were an option, it would be incorrect as it's a less common site for metastasis compared to others.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that Wilm's tumor can spread to any site but has a predilection for the **lungs** and **liver** due to hematogenous spread. Early detection and treatment are crucial for prognosis.
**Correct Answer:** Correct Answer: D. Lungs.