CHEVY CHASE, Md. (WUSA) — Early detection is key to a positive skin cancer prognosis. But how do you know when a suspicious mole is possibly a melanoma, the more aggressive form of skin cancer?

Moles, brown spots, and growths on the skin are usually harmless but not always.

Mary Lynn Reede, who has lots of them, doesn't take any chances. She slathers on the sunscreen, does skin self-checks and sees Dr. Maral Skelsey on an annual basis, sometimes twice a year for a full body scan.

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All of this to check herself for and to protect herself from melanoma.

"If she finds anything suspicious or changes in color or gotten larger,” Reede said. “Then typically she'll say we need to do a biopsy to make sure it's not cancer or pre-cancer."

But instead of a biopsy, Dr. Skelsey tried a new, noninvasive procedure on Reede. It's called DermTech — particularly good for patients like her who have 50 or more moles — a risk factor for melanoma.

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With DermTech, there is no need to cut the skin for a specimen. Dr. Skelsey just places the thin DermTech adhesive patch over the mole to lift off skin cells for analysis and can repeat this at least four times without an anesthetic.

"It saves the whole experience of the injection, cutting the mole out, the stitching, coming back,” the DermTech patient said. “It was really an amazing difference."

DermTech has its limitations. It cannot detect other, more common types of skin cancers. And at this point, DermTech cannot be used on darkly pigmented skin, the scalp, palms, soles of feet or inside the mouth.

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