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"How can one tell is a mole is cancerous?"

ZocdocAnswersHow can one tell is a mole is cancerous?


How do you know for sure if a mole is cancerous? I've had a large, brown mole on my chest since I was a kid, but recently I'm pretty sure it has been growing. Is there any good way for me to tell whether it's cancerous, or do I just have to take it to a doctor? How would a doctor decide?


There are some general rules to keep in mind when assessing moles for cancer risk. It is possible to keep track of some of your moles with self-checks and indeed this is an important step in catching melanoma (skin cancer) early. However, an annual mole check by a physician is still necessary, especially in very fair-skinned individuals or individuals with multiple moles (or 'nevi'--the medical term for moles). When doing a self-assessment of moles, it is useful to follow the simple mnemonic ABCD: A is for Asymmetry, if one side of the mole looks different than the other then the mole should be checked B is for Borders: ragged, uneven or notched borders are worrisome C is for Color: change in color or multiple different colors in the same mole are worrisome D is for Diameter: any mole greater than 6mm should be checked Other warning signs include: -any change in shape, size or color in a mole. -burning, itching or bleeding from the mole -redness or swelling around the mole All these self-exam tips should not replace a yearly check-up by your physician. Also, keep in mind one of the best ways to prevent skin cancer is limiting sun exposure and daily use of sunblock. Hope this helps!

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