## **Core Concept**
Vulval carcinoma is a type of cancer that affects the vulva, which is the external female genital area. The metastatic pattern of vulval carcinoma typically involves local lymph nodes before spreading to more distant sites. Understanding the lymphatic drainage of the vulva is crucial for predicting metastatic spread.

## **Why the Correct Answer is Right**
The correct answer, **inguinal lymph nodes**, is right because the vulva primarily drains into the inguinal lymph nodes. The lymphatic drainage of the vulva is mainly to the superficial and deep inguinal lymph nodes. From there, cancer cells can spread to other lymph node groups and eventually to distant organs. This pattern of lymphatic drainage explains why inguinal lymph node involvement is a significant prognostic factor in vulval carcinoma.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because while pelvic lymph nodes can be involved, especially in more advanced disease, they are not the primary site of metastasis for vulval carcinoma.
- **Option B:** This option is incorrect as it does not specify a recognized primary site for vulval carcinoma metastasis.
- **Option C:** This option is incorrect because, although distant organs can be sites of metastasis in advanced vulval carcinoma, they are not the initial or most common site of metastasis.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the involvement of inguinal lymph nodes significantly affects the prognosis and management of vulval carcinoma. Sentinel lymph node biopsy is a technique used to assess whether the cancer has spread to the lymph nodes, helping guide treatment decisions.

## **Correct Answer:** D. inguinal lymph nodes.