How to Check Your Skin After Summer: A Mohs Surgeon's Step-by-Step Self-Exam

After a summer outdoors, most people take a closer look at their skin. Very few have been shown what to actually look for. The advice that circulates online covers melanoma and stops there, which leaves out the two skin cancers I remove most often.

I am a board-certified dermatologist and a Mohs micrographic surgeon. Mohs surgery removes skin cancer layer by layer, which means I spend my days looking at what these cancers become when nobody catches them early. This is what I tell my patients.

What does the ABCDE rule miss?

The ABCDE rule screens for melanoma, and melanoma is the minority of skin cancer cases. Basal cell carcinoma and squamous cell carcinoma are far more common, and neither one behaves like a mole. Asymmetry, border, color, diameter and evolving are useful questions to ask about a pigmented spot. They are close to useless for a lesion that arrives as a bump or a rough patch.

That gap matters, because the two cancers I treat most often are also the two most likely to be dismissed. They look like ordinary skin complaints, so people wait.

The checklist most people know is built for melanoma. Most of what I remove does not look anything like that.Dr. Lindsay D. Sewell, MD MBA

What do basal cell and squamous cell carcinoma look like?

Basal cell carcinoma usually appears as a pearly or translucent bump, often with tiny visible blood vessels running across it. Patients tell me they thought it was a stubborn pimple that kept bleeding and scabbing and never cleared. Squamous cell carcinoma tends to show up as a rough, scaly red patch or a crusted growth that resembles a wart, and patients assume it is dry skin or eczema.

The most useful sign is not the shape. It is the pattern over time. If a spot bleeds easily, scabs over, appears to heal, then bleeds again a few weeks later, I want to biopsy it. That cycle is the single most reliable warning your skin gives you.

Sign	Mistaken for	What to do
Pearly or translucent bump with tiny blood vessels	A pimple that keeps bleeding and never clears	Book an appointment
Rough, scaly red patch or crusted growth	Dry skin or eczema	Book if moisturizer does not resolve it
Sore that bleeds, scabs, then bleeds again	A scratch or a slow-healing cut	Book if it is not healed in a month
Mole that is new, growing or changing color	A normal mole that has always been there	Photograph it and book
Dark streak under a fingernail or toenail	A bruise from an injury	Book an appointment

How do you check your own skin at home?

I keep this simple, because a routine people remember beats a routine they abandon. Set a reminder. Look closely at the parts you can see, in good light, with a full-length mirror and a hand mirror. Get someone to look at the parts you cannot. Start at your face, neck and ears, then work down: chest and belly, both sides of your arms including underarms and palms, the front and sides of your legs, the tops and soles of your feet, and between your toes. Use the hand mirror for the back of your neck, your shoulders, your back, your buttocks and the backs of your legs. Part your hair in sections to check your scalp.

Get familiar with your own spots so you can tell what is new. If you have too many to keep track of, photograph them. You are carrying a good camera already, so use it. Keep the lighting, the angle and the time of day consistent between photos, and make sure the spot is actually in focus. I have seen plenty of blurry lesions with a perfectly sharp dog in the background.

Which areas do people miss most often?

My patients are good at checking whatever they can see by looking down. Arms, legs, chest and abdomen get covered thoroughly. The scalp, the back, behind the ears, the groin, the buttocks, the soles of the feet and the skin between the toes get skipped, and those are where I most often find something that was missed.

The scalp and back are close to impossible to examine properly on your own, even with two mirrors. Ask a partner or a family member. It takes two minutes and it covers the areas most likely to hide something.

One more habit worth building. Most of your moles look like one another, so the one that does not fit the pattern is the one I want to see. I ask patients if they remember the Sesame Street song about one of these things not being like the others. That is the whole idea. Your spots should not all go bad at once, so the outlier is the one that gets checked.

Does a summer tan change what you see?

Yes, and not in a helpful way. A tan darkens your existing moles, which can make a normal spot look more concerning and a concerning spot harder to pick out. That is part of why more biopsies happen at the end of the summer.

It also works the other way, and this is the part I find myself explaining most. Sun damage takes years to become a skin cancer. A melanoma found at the end of August did not come from the sun you got in June. A bad burn this summer is a reason to protect yourself better from here, not the cause of what you are looking at today. Correlation is not causation, and nobody should spend their diagnosis blaming one bad weekend.

When should you call a dermatologist?

Call now for anything new or changing, anything that meets the ABCDE signs, a sore that has not healed in about a month, a painful spot, or a lesion that bleeds and scabs repeatedly. If everything looks stable and nothing is new, it can wait for your next scheduled visit.

There is no single right interval for a professional exam. It depends on your number of moles, your burns, your time in the sun or in a tanning bed, your family history, your age and your skin type. For lower-risk adults over about 30, once a year is the usual answer. The more risk factors you carry, the more often you should be seen.

If you cannot get in for a month or more and something is changing quickly, most primary care providers can perform a biopsy. A biopsy-proven problem also tends to move you up the referral list.

The most common reason people wait is denial dressed up as reasoning. It is just a pimple. Then months go by.Dr. Lindsay D. Sewell, MD MBA

I saw a man in his 50s early in my career with a nonhealing black open wound. His family had been trying to get him to come in for years. He refused.

The biopsy confirmed malignant melanoma. His regional lymph nodes were golf ball sized instead of pea sized. A CT scan showed the cancer in his liver, his lungs, his spleen and throughout his chest cavity. He told me he had never felt better, that he felt as young as he did in his 20s. I had to tell him it did not matter. There was not much left to do. This was before immunotherapy, and chemotherapy for metastatic melanoma was weak at best.

He died a couple of months later. He could still be here today. His family had noticed a changing mole years earlier, and that was the moment. So sad.

What does sun protection look like after a clean skin check?

Do not let the sun touch your skin directly. Keep a layer between the two: shade, sun protective clothing, a wide-brimmed hat, sunglasses, an umbrella, sunscreen. Used as directed with other sun protection measures, a broad-spectrum SPF 15 or higher helps decrease the risk of skin cancer and early skin aging caused by the sun. Keep a hat and a light long-sleeve layer in your car so a change of plans does not turn into a burn. Do the things you enjoy. Do them protected. You wear a seatbelt and you wear a helmet, and this belongs in the same category.

For daily wear, SolRX Mineral SPF 50 Zinc is a zinc oxide formula with 8-hour water resistance and no white cast, which makes it workable on face and body without a separate product for each. For the places people reapply least, the Clear Zinc Face Stick SPF 50 covers ears, nose and the back of the neck without a mirror or clean hands.

If this was useful, I have also written about sunscreen after laser, IPL and retinol, and about why sunscreen is the most powerful anti-aging tool you have. For product-level guidance, SolRX has a guide to the best sunscreen for skin cancer prevention.

Want a printable version of this self-exam? Download the SolRX Skin Check Guide, which I reviewed, and keep it somewhere you will actually see it.