All of the following statements hold true for melanoma of vulva except :
Melanoma is a type of skin cancer that arises from melanocytes. The vulva is a common site for melanoma, especially in older women. I remember that vulvar melanoma tends to have a worse prognosis compared to melanomas in other areas. This might be due to delayed diagnosis because the symptoms can be mistaken for other conditions like eczema or lichen sclerosus.
Now, looking at the options, the incorrect statement would be one that contradicts these facts. Let's consider possible options. For example, if an option says "It is more common in young women," that's incorrect because it's more common in older women. Another possible wrong option could be about the 5-year survival rate being high, but actually, it's lower due to late presentation. Also, if an option states that it's usually pigmented, that's correct, but if it says it's non-pigmented in most cases, that's wrong.
Wait, the question is about the exception. So the correct answer is the one that doesn't fit. Let me think of standard incorrect statements. One common misconception is that vulvar melanoma is less aggressive than other melanomas, but actually, it's more aggressive. Another is that it's the most common type of vulvar cancer, but actually, squamous cell carcinoma is more common. So if an option claims it's the most common, that's incorrect.
Putting it all together, the incorrect statement would be something like "Vulvar melanoma is the most common type of vulvar cancer," since squamous cell carcinoma is the most common. Alternatively, if an option says it's typically superficial, but in reality, it tends to be thicker at diagnosis, leading to worse outcomes.
I need to structure the explanation with the core concept, why the correct answer is right, why others are wrong, a clinical pearl, and the correct answer line. Let me make sure each part is accurate and concise. Let me verify the facts: vulvar melanoma is indeed more aggressive, often presents late, and squamous cell is more common. So the incorrect statement would be the one that says it's the most common vulvar cancer.
**Core Concept**
Vulvar melanoma is a rare but aggressive malignancy arising from melanocytes in the vulvar skin. It accounts for ~5% of vulvar cancers and has distinct clinical features, including late presentation and poor prognosis compared to other melanomas.
**Why the Correct Answer is Right**
The incorrect statement is **Option C: "Vulvar melanoma is the most common type of vulvar cancer."** Squamous cell carcinoma (SCC) is the most common vulvar malignancy (80–90% of cases), while melanoma comprises 5–10%. SCC typically affects older women and is associated with human papillomavirus (HPV) in some cases. Melanoma, though less frequent, has higher metastatic potential and worse survival rates due to delayed diagnosis.
**Why Each Wrong Option is Incorrect**
**Option A:** "It often presents as a pigmented lesion" is correct. Vulvar melanoma typically appears as a pigmented n