**Core Concept**
Vulval cancer is a type of malignancy that affects the vulva, the external female genitalia. The initial presentation of vulval cancer often involves nonspecific symptoms, making it challenging to diagnose at an early stage. Pruritus, or itching, is a common symptom in various dermatological conditions, including vulval cancer.

**Why the Correct Answer is Right**
Pruritus is the first symptom in vulval cancer due to the local spread of cancer cells, which can cause inflammation and irritation of the vulval skin. This leads to intense itching, which may be severe and persistent. In vulval cancer, pruritus is often the initial symptom, followed by other signs such as ulceration, bleeding, and pain. The exact mechanism involves the release of various inflammatory mediators, including histamine, which stimulates nerve endings and causes itching.

**Why Each Wrong Option is Incorrect**
**Option A:** Pain is a symptom that may occur in advanced stages of vulval cancer, particularly if the cancer has invaded deeper tissues or nerves.

**Option C:** Ulceration is a possible symptom of vulval cancer, but it is not typically the first symptom. Ulceration usually occurs as a result of local tissue destruction and is often accompanied by other symptoms such as pruritus and bleeding.

**Option D:** Bloody discharge is not a common initial symptom of vulval cancer. While bleeding may occur in advanced stages, it is often accompanied by other symptoms such as pruritus, ulceration, and pain.

**Clinical Pearl / High-Yield Fact**
A classic clinical correlation for vulval cancer is the "ABC rule," which stands for Asymmetry, Borders, and Color. If a vulval lesion has an irregular shape (asymmetry), poorly defined borders, or an abnormal color, it should raise suspicion for vulval cancer.

**✓ Correct Answer:** B. Pruritus