How to Tell if Mole is Cancerous?

I was noticing a little brown mole on my skin, and I stupidly thought it was something else so I picked it off. It went really red and it has swollen up with a red outline. Now, the mole is dark brown and I'm not sure whether or not it is just a scab. It does not itch or anything; it just stings a bit when I touch it. How would I know if it is cancerous or not?

Doctor Answers 7

The ABCD's of Moles

Dr. Ebrahim checks suspicious moles using the ABCD rule: 



Color or color change

Diameter – diameter larger than .06 mm

Evolution of the mole- changing or evolving

Dr. Ebrahim, in her Dermatology clinic uses Dermoscopy to evaluate moles.  The dermatascope provides

10 times magnification which  allows her to see deeper structures of the mole.  Dr. Ebrahim recommends that you have any suspicious moles evaluated by a Physician for peace of mind. 

Vancouver Physician
4.9 out of 5 stars 9 reviews

How to tell if a mole is cancerous

The only way to tell if a mole is cancerous is to find an experienced board certified dermatologist with a knowledge of skin cancer.  It sounds like the mole needs to be sent to the pathology lab to determine what exactly it is.  Try not to scratch it because this can make it appear more irritated or infected.

Michele S. Green, MD
New York Dermatologist
5.0 out of 5 stars 76 reviews

Evaluation of mole

I would encourage you to allow the lesion to heal and then carefully have it evaluated.  When evaluating a mole/lesion for skin cancer we refer to the ABCD's of melanoma.  The only way to know if a lesion cancerous or not is to get a biopsy.

Sam Naficy, MD, FACS
Seattle Facial Plastic Surgeon
4.7 out of 5 stars 221 reviews

How to Tell if Mole is Cancerous?

It would be a wonderful thing if we could know who are enemies are but just looking at them. Unfortunately, all the "bad" guys do not wear black hats, wear black sunglasses or stroke a white Persian cat while laughing demonically.  To recognize many skin moles based on their appearance requires years of medical training and seeing thousands of moles. But even then, surgeons may underestimate a and mistake a mole thinking it is benign when in fact it could be a cancer.

The BEST way to tell what a mole is is to have is removed surgically and have a trained skin Pathologist examine it under the microscope. This will almost always pick an early cancer and prevent a delay in treatment. Anything less than this is a bet that the mole is benign and a compromise of your care. I would have it biopsied by a dermatologist or a Plastic surgeon.

Dr. Peter A Aldea

Peter A. Aldea, MD
Memphis Plastic Surgeon
4.9 out of 5 stars 108 reviews

If you pick at a mole, can it turn into cancer?

See below for my live interview on MSNBC recently about how to tell if a mole is bad. The trouble with evaluating a recently picked or traumatized mole, is it really can look bad while healing, and then turn out fine, so don't panic. Allow a mole to heal if you know you have picked at it, and THEN evaluate it. If it doesn't heal normally, or looks different after healing than it did before, go to a dermatologist for a biopsy removal of it, so it can be sent in to have the tissue checked under a microscope.

Don't panic, most likely a picked mole doesn't change if it was benign before.

Jessica J. Krant, MD, MPH
New York Dermatologic Surgeon
4.7 out of 5 stars 41 reviews

How to tell if mole picked at is cancerous

You can't tell on your own if a mole is cancerous. Refer to the answer above from Dr. Seify on the ABCD's of melanoma.

If the mole is new, it could be problematic. The appearance of the mole BEFORE your attempt to pick it off is the key.

In any event, you may have caused an infection so your best option is to visit with a dermatologist. Everyone should get annual skin cancer checks so perhaps this is your first reason to get that started.

Mole removal is accomplished in a variety of ways. One new system is a small 2mm ablative laser handpiece that is part of the Fraxel Repair laser system and is good for superficial mole removal as it reduces scar risk.

Deeper moles may still need to be surgically excised but a good cosmetic dermatologist of even plastic surgeon will be able to accomplish this with excellent results.

Nissan Pilest, MD
Irvine Dermatologic Surgeon
4.7 out of 5 stars 19 reviews

The ABCD system to detect melanoma

The famous ABCD system for melanoma detection was first proposed in 1985 and since that date, it helped in early detection of mailgnant transformation in pigmented lesions:

A: Asymmetry of the lesion.

B: Border varigation and uneveness.

C: Color--darker colors, especially when a recent change occured, is considered as one of the most important signs.

D: Diameter--Increase in size is also very important.

In general, patients with large number of pigmented lesions are usually followed by their dermatologist and even photos will be taken for documentation. In case of doubt a quick biopsy is the safest thing to do.

Hope that helps.

Hisham Seify, MD, PhD, FACS
Orange County Plastic Surgeon
5.0 out of 5 stars 19 reviews

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.