Having a low threshold to biopsy atypical pigmented lesions on the vulva may identify melanoma early, according to a lecture at virtual conference on diseases of the vulva and vagina, hosted by the International Society for the Study of Vulvovaginal Disease.
Pigmented brown or black vulvar lesions occur in approximately 10% of women, and they may be normal and benign.
“Often we will see a pigmented lesion on the vulva and think that there is nothing to worry about,” said Melissa Mauskar, MD.
Lesions could be angiokeratomas, petechiae, purpura, melanosis, and nevi, for example. Seborrheic keratoses can mimic melanoma. “If it looks odd, don’t be afraid to biopsy it,” said Dr. Mauskar , assistant professor of dermatology and obstetrics and gynecology at the University of Texas Southwestern Medical Center in Dallas.
Characteristics of melanoma, covered by the mnemonic ABCDE, include asymmetry, borders that are irregular, coloring that is uneven, diameter greater than 7 mm, and evolution over time.
When biopsying a lesion because of concerns about melanoma, the goal is to remove the whole lesion at once, Dr. Mauskar said.
In a recent U.S. population-based study of more than 1,800 patients with malignant melanoma of the vulva or vagina (including 1,400 patients with vulvar melanoma and 463 patients with vaginal melanoma), median disease-specific survival was 99 months for vulvar melanoma and 19 months for vaginal melanoma.
Patients with vaginal melanoma were more likely than patients with vulvar melanoma to have nodular lesions. The American Joint Committee on Cancer staging system predicts vulvar melanoma outcomes, the researchers found. In addition, lymph node status and mitotic rate were important predictors of survival.
A wide local excision is the mainstay of therapy for melanoma. Other therapeutic advances are “changing the survival curves for these patients, especially when we can find things early,” Dr. Mauskar said.
Photographing lesions can help doctors monitor them over time, she added.
It is important for dermatologists to include the vulva in skin exams and for gynecologists to have a low threshold to biopsy atypical pigmented lesions, Dr. Mauskar said. “Having a very low threshold for biopsy ... will increase our chances of finding these lesions when they are more at the superficial spreading phase as opposed to the nodular phase,” she said.
Capturing the depth of a tumor within the confines of a biopsy may help accurately stage malignant melanoma, Jason Reutter, MD, a pathologist in Hickory, N.C., said in a separate presentation. He suggested trying to get around the lesion with a punch biopsy if possible. A shave biopsy may be advantageous for larger macular lesions. To diagnose one melanoma, doctors may have to biopsy many lesions, Dr. Reutter noted.
At one institution, the number of skin biopsies needed to diagnose skin cancer ranged from 2.82 to 6.55, depending on the type of clinician, according to a recent study. The number of biopsies needed to detect one melanoma was greater – between 14 and 54 – depending on type of clinician.
For larger lesions, scouting biopsies of different areas may be the best approach, Dr. Reutter said.