The vulva is the external part of the female genitalia, playing a vital role in sexual function, urination, and overall well-being. Understanding its location and anatomy is crucial for women’s health. The vulva is situated in the perineal region, below the abdomen and in front of the anus. It encompasses several structures, each with a specific function.
The vulva is composed of two sets of labia, or lips, surrounding the vaginal opening. The outer lips, known as the labia majora, are more substantial and typically covered with hair on the outer surface after puberty. These folds are analogous to the scrotum in males. Inside the labia majora are the labia minora, thinner, hairless folds of skin that directly enclose the vaginal opening. The labia minora are highly sensitive and rich in nerve endings.
At the anterior meeting point of the labia minora is the prepuce, a hood-like structure that covers and protects the clitoris. The clitoris is a small, highly sensitive organ, primarily composed of erectile tissue. It is the main center for sexual pleasure in females, becoming engorged with blood during sexual stimulation.
Just below the clitoris, between the labia minora, lies the opening of the urethra, the tube through which urine exits the body from the bladder. Further down is the vaginal opening. On either side of the vaginal opening are the Bartholin glands. These glands secrete a mucus-like fluid that lubricates the vagina, particularly during sexual intercourse.
Posteriorly, the labia minora converge at the fourchette, a small fold of skin located just behind the vaginal opening. Beyond the fourchette and vaginal opening is the perineum, the area of skin and tissue between the vagina and the anus. The anus, the opening of the rectum, is where stool is expelled from the body.
While generally a healthy part of the body, the vulva can be affected by various conditions, including cancer. Vulvar cancer, although rare, most commonly develops on the inner edges of the labia majora or labia minora. It can less frequently originate in the clitoris or Bartholin glands.
Types of Vulvar Cancer
Cancer arises when cells in the body begin to proliferate uncontrollably and can spread to other parts of the body. Vulvar cancer is categorized into different types based on the cells where the cancer originates.
Squamous Cell Carcinomas
The majority of vulvar cancers are squamous cell carcinomas. These cancers originate in squamous cells, the primary type of skin cells. Several subtypes exist within squamous cell carcinoma:
- Keratinizing squamous cell carcinoma is the most prevalent subtype, typically occurring in older women and not associated with human papillomavirus (HPV) infection.
- Basaloid and warty squamous cell carcinomas are less common and are more frequently observed in younger women with HPV infections.
- Verrucous carcinoma is a rare, slow-growing subtype that resembles a large wart and generally has a favorable prognosis. A biopsy is necessary to differentiate it from benign growths.
Adenocarcinoma
Adenocarcinoma is cancer that begins in gland cells. Approximately 8% of vulvar cancers are adenocarcinomas. Vulvar adenocarcinomas most often originate in the Bartholin glands, which are situated near the vaginal opening. Cancer of the Bartholin gland can be easily mistaken for a cyst, potentially delaying accurate diagnosis. Adenocarcinomas can also develop in the sweat glands of the vulvar skin.
Paget disease of the vulva is a condition characterized by adenocarcinoma cells in the top layer of vulvar skin. Up to 25% of individuals with vulvar Paget disease also have invasive vulvar adenocarcinoma in a Bartholin gland or sweat gland. In other cases, the cancer cells are confined to the skin’s surface and have not invaded deeper tissues.
Melanoma
Melanomas are cancers that develop in pigment-producing cells (melanocytes) that give skin its color. While more common in sun-exposed skin areas, melanomas can also occur in less exposed areas like the vulva. Vulvar melanomas are rare, accounting for about 6% of all vulvar cancers.
Sarcoma
Sarcomas are cancers that originate in the cells of bones, muscles, or connective tissue. Vulvar sarcomas are very rare, representing less than 2% of vulvar cancers. Unlike other types of vulvar cancer, sarcomas can occur in females of any age, including children.
Basal Cell Carcinoma
Basal cell carcinoma, the most common type of skin cancer overall, is rarely found on the vulva. It is typically associated with sun-exposed skin.
Understanding the location and anatomy of the vulva, as well as the types of cancers that can affect it, is important for women’s health awareness. Regular self-exams and awareness of any changes in the vulvar area are crucial for early detection and prompt medical attention if needed.
