Ask Dr. Pat: Does Vulvar Melanoma Always Look Like the Photos in the Textbooks?

August 13, 2012 by  
Filed under Cancer, Health

 

Dear Dr. Pat,

I had a melanoma on my leg five years ago.  It was caught really early, and simple wide removal of tissue around the small mole was a cure.  My gynecologist knew about my history.  I asked her if I should have a small, flat mole, that was skin colored but new, removed from the area between my vagina and the anal area.  She told me that it was “just a skin tag.” I have seen this gynecologist for many years and have always been pleased with her care.  However, this mole, even though it was not black, not raised, not irregular in outline, and was smaller than a pencil eraser and was in an area never exposed to the sun, was new.  So, I went to see the skin cancer doctor who had diagnosed the previous melanoma.  He felt that this new mole should be removed.  It was indeed another melanoma, once again, caught early.  Why did my gynecologist decide not to remove this?

Pamela

Dear Pamela,

There are rare melanomas that do not contain pigment and are flesh colored. These melanomas unfortunately are often overlooked on an exam or not regarded as potentially malignant because they do not fit the usual “A B C D” guidelines for malignant moles .   When a patient reports that a genital lesion is new, a small biopsy, sent to a laboratory that specializes in skin cancer work, is generally the best choice of action.  Often patients do not want to have lesions removed, and generally the diagnosis turns out to be benign—which further annoys the patient.  However, gynecologists need to inform patients of the risk of leaving new genital lesions undiagnosed while sharing the information that most of these lesions will not be malignant.  In the world of vulvar cancer it is always better to do that biopsy.  Dr. Elizabeth Poynor wrote a very helpful piece on vulvar melanoma that we are re-posting below.

Patricia Yarberry Allen, M.D.


 

Pigmented Lesions of the Vulva – Yes, You Can Get Melanoma ‘Down There!’

By Dr. Elizabeth Poynor

The vulva refers to the external female genitalia, which include the labia, the opening of the vagina, the clitoris, and the space between the vagina and the anus. Because these areas are not sun-exposed, it is not generally recognized by women that melanoma can develop in this location.

Lesions such as moles and freckles—referred to as pigmented lesions—occur on the vulva of 10 percent to 12 percent of women. It is not uncommon for women to have typical moles in the vulvar region. Like other typical moles, most of these are benign and can cause no further problems. However, it is important that women be aware that moles can exist on the vulva, and some of these may have premalignant or malignant changes in them, just as moles do in other parts of the body. Women should be aware that the change in any mole, such as a change in color or size, should always be brought to the attention of their gynecologist and evaluated.

Other benign pigmented lesions include lentigines, also known as freckles; melanosis, the accumulation of pigment deposits; post-inflammatory hyperpigmentation, a collection of pigment in reaction to trauma and other skin conditions; seborrheic keratosis; hemangiomas; and warts.

Benign nevus. (University of Utah)

Moles, or melanocytic nevi, are composed of nests of melanocytes, the cells that produce the pigment of the skin. Melanocytic nevi commonly form during early childhood and occur as a response to sun (ultraviolet) exposure. However, genetic factors are also in the development of some types of melanocytic nevi. Moles may transform into the potentially lethal form of skin cancer, melanoma. The true frequency of transformation of a melanocytic nevus into melanoma is not known, and the estimated prevalence varies widely. The main clinical concern is distinguishing between a benign nevus, a dysplastic nevus, and a melanoma.

Dysplastic nevus. (Webster’s)

Dysplastic nevi contain atypical looking cells, which do not meet the criteria for melanoma and may be a precursor of or marker of melanoma. These should usually always be completely excised.
Approximately 3 percent of all melanomas are located in the genital tract. Melanoma of the vulva accounts for 5 to 7 percent of invasive vulvar cancers and has an estimated annual incident rate of 1 per 1 million women. The disease can affect women of all ages, but is more common in the older population, with almost half of the patients aged 70 years or older.

More than 90 percent of melanomas occur in white women. Vulvar melanoma usually occurs on the labia minora or the clitoris; signs of vulvar melanoma can include a black or brown raised area or a change in the size, shape, or color of a pre-existing mole. Melanoma of the vulva has a poorer prognosis overall than melanoma on the torso, most likely because of the extent of the disease at the time of diagnosis. If the disease has not invaded the deeper layers of the skin, the cure rate is close to 100 percent, and cure is reported to be as high as 99 percent with invasion of 1.5 mm or less. The survival rate drops to 65 to 70 percent if the lesion invades 1.5-4 mm. Melanoma is usually treated with surgical excision and evaluation of the regional lymph nodes.

Melanoma. (Wikimedia Commons)

Improving mortality and survival—with this potentially lethal disease—depends on early recognition, and experience counts.  Management includes careful inspection of the vulva with each full-skin or gynecologic examination, and biopsy of any suspicious lesion.

A skin biopsy is required when clinical diagnosis is inadequate or when malignancy is suspected. When the diagnosis or management of these lesions is uncertain, medical professionals should [not hesitate to]  refer patients to individuals with special expertise in pigmented lesions of the vulva, such as gynecologist oncologists, melanoma surgeons, and dermatologists. The stakes are high, and experience counts.

Once a biopsy has been performed on a lesion and a histopathological diagnosis has been made, strong consideration should be given to the possibility of consultation with a board-certified dermatopathologist, a pathologist with a special expertise with pathology of the skin.

A woman should note any change in appearance in her vulvar skin, or pain or itching, to her physician. Women may also need to be persistent about getting a diagnosis, since many women with vulvar cancer may see multiple physicians prior to getting a diagnosis. Regular gynecological examinations are necessary to detect precancerous conditions that can be treated before the cancer becomes invasive. Since some vulvar cancer is a type of skin cancer, the American Cancer Society also recommends self-examination of the vulva using a mirror. If moles are present in the genital area, use the ABCD rule:

  • Asymmetry. A cancerous mole may have two halves of unequal size.
  • Border irregularity. A cancerous mole may have ragged or notched edges.
  • Color. A cancerous mole may have variations in color.
  • Diameter. A cancerous mole may have a diameter wider than 6 millimeters (1/4 inch).

If you have any questions, ask your physician for an exam and, if necessary, biopsy, and be aware of your vulvar skin. When you perform your general skin checks, do not forget the vulva; checking could save your life.

A member of the WVFC Medical Advisory Board, Dr. Elizabeth Poynor is a practicing gynecologic oncologist and pelvic surgeon, with a Ph.D. in cell biology and genetics. Her private practice in New York focuses on cancer diagnosis, prevention and treatment.