Skin Self-Exam: How to Check for Skin Cancer

What Is a Skin Self-Exam and Why Is It Important?

A skin self-exam is a visual inspection of your entire body to identify suspicious moles, growths, or skin changes that could indicate skin cancer. Performing monthly self-exams significantly increases early detection rates, which is critical because early-stage melanoma has a 5-year survival rate exceeding 99%.

Skin cancer is the most common form of cancer worldwide, affecting millions of people each year. According to the American Cancer Society, one in five Americans will develop skin cancer by age 70. However, when detected early, skin cancer is highly treatable, with excellent outcomes for patients. This is why regular skin self-examinations are so important—they empower you to become an active participant in your own health care.

The primary goal of a skin self-exam is to become familiar with your own skin so you can quickly notice any changes. Your skin is unique, with its own pattern of moles, freckles, and birthmarks. By examining your skin regularly, you develop what dermatologists call "body awareness"—the ability to recognize when something new appears or when an existing spot changes in size, shape, or color.

Studies have shown that patients who perform regular skin self-exams are more likely to detect melanoma at an earlier, more treatable stage. A landmark study published in the Journal of the American Academy of Dermatology found that people who examined their skin monthly were significantly more likely to discover thin melanomas (less than 1mm thick) compared to those who did not perform self-exams. Thin melanomas have a much better prognosis than thicker tumors.

Beyond detecting potentially cancerous lesions, regular skin self-exams also help you notice other skin changes that may warrant medical attention, such as precancerous spots (actinic keratoses), unusual rashes, or infections. This proactive approach to skin health complements professional dermatological examinations and creates a comprehensive surveillance system for your largest organ.

The Three Main Types of Skin Cancer

Understanding the different types of skin cancer can help you know what to look for during your self-exam. Each type has distinct characteristics and risk factors.

Melanoma is the most dangerous form of skin cancer, but it is also the least common of the three main types. Melanoma develops in the cells that give your skin its color (melanocytes) and can spread to other parts of the body if not caught early. It often appears as a new dark spot or a change in an existing mole. The ABCDE criteria are specifically designed to help identify melanoma.

Basal cell carcinoma (BCC) is the most common type of skin cancer, accounting for about 80% of all skin cancer cases. It typically appears as a pearly or waxy bump, a flat flesh-colored or brown scar-like lesion, or a bleeding or scabbing sore that heals and returns. BCC rarely spreads to other parts of the body but can cause significant local damage if left untreated.

Squamous cell carcinoma (SCC) is the second most common type of skin cancer. It often appears as a firm red nodule, a flat lesion with a scaly or crusted surface, or a new sore or raised area on an old scar. SCC can spread to other parts of the body if not treated, though this is relatively uncommon when caught early.

What Is the ABCDE Method for Checking Moles?

The ABCDE method is a proven system for evaluating moles and identifying potential melanomas: A = Asymmetry, B = Border irregularity, C = Color variation, D = Diameter over 6mm, and E = Evolving changes. This simple memory tool helps you systematically assess each mole during your self-exam.

Developed by dermatologists as an educational tool for both healthcare providers and the public, the ABCDE criteria provide a standardized approach to evaluating pigmented skin lesions. Research has demonstrated that using these criteria significantly improves the detection of melanoma, particularly among non-specialists. The system transforms the complex task of mole assessment into a straightforward checklist that anyone can apply.

While the ABCDE criteria are highly useful, it's important to understand that not all melanomas will meet every criterion, and not all moles that meet some criteria are necessarily cancerous. The system is designed to help you identify moles that warrant professional evaluation, not to provide a definitive diagnosis. When in doubt, always consult a dermatologist.

The "Ugly Duckling" Sign

In addition to the ABCDE criteria, dermatologists recommend watching for the "ugly duckling" sign. This concept is based on the observation that most of a person's moles look similar to each other—they share common characteristics in terms of size, shape, and color. An "ugly duckling" is a mole that stands out from the rest, looking noticeably different from your other moles.

The ugly duckling sign is particularly useful because it takes advantage of your familiarity with your own body. Even if a suspicious mole doesn't meet the classic ABCDE criteria, the fact that it looks different from your other moles should prompt you to have it evaluated by a dermatologist. Studies have shown that the ugly duckling sign can help identify melanomas that might otherwise be missed.

How Do You Perform a Complete Skin Self-Exam?

A complete skin self-exam involves systematically examining every part of your body in a well-lit room using a full-length mirror, hand-held mirror, and good lighting. The exam should cover your entire skin surface, including often-missed areas like the scalp, between toes, and under nails, and typically takes 10-15 minutes.

Performing a thorough skin self-exam requires some preparation and a systematic approach. The goal is to examine every square inch of your skin, including areas you might not think to check. Having the right tools and a consistent routine will make the process more effective and help ensure you don't miss any areas.

Before you begin, gather the supplies you'll need: a full-length mirror, a hand-held mirror, good lighting (natural light is ideal), a hair dryer or comb for examining your scalp, and optionally, a smartphone for taking photos of moles you want to track. Find a private, well-lit room where you can undress completely. Many people find it helpful to perform their self-exam after a bath or shower.

Step-by-Step Examination Guide

Step 1: Face and Head
Stand in front of a full-length mirror with good lighting. Begin by examining your face carefully, including your nose, lips, mouth, and the areas around your eyes. Use your fingers to feel along your eyebrows and examine behind and inside your ears. Many skin cancers develop on the face due to sun exposure, so take your time with this area.

Step 2: Scalp
Your scalp is one of the most commonly missed areas during self-exams, yet skin cancer can definitely develop there. Use a hair dryer set on cool to part your hair systematically, examining your entire scalp from your forehead to the back of your neck. If you have difficulty seeing your scalp, ask a family member or friend to help. People with thinning hair or bald spots should pay particular attention to these sun-exposed areas.

Step 3: Hands and Arms
Examine both the front (palms) and back of your hands, including between your fingers and under your fingernails. Melanoma can develop under the nails, appearing as a dark streak. Continue up your wrists, forearms, and upper arms. Don't forget to lift your arms and examine your underarms, which are often overlooked.

Step 4: Torso
Check your neck, chest, and abdomen in the mirror. Women should lift their breasts to examine the skin underneath. Use the hand-held mirror to view your back, or have someone help you examine this hard-to-see area. The back is a common site for melanoma, especially in men. Also examine your shoulders and the back of your neck.

Step 5: Lower Body
Examine your buttocks and genital area using the hand-held mirror. While skin cancer is less common in areas not exposed to the sun, it can still occur there. Continue by examining your thighs, both front and back, your knees, and your lower legs. Use the hand-held mirror to see the backs of your legs clearly.

Step 6: Feet
Sit down to examine your feet thoroughly. Check the tops, soles, between your toes, and under your toenails. The soles of the feet are another commonly missed area where melanoma can develop, particularly a type called acral lentiginous melanoma that is more common in people with darker skin tones.

What Are the Warning Signs to Watch For?

Key warning signs include any new mole appearing after age 30, rapid growth or change in an existing mole, moles with irregular borders or multiple colors, sores that don't heal within 3 weeks, and any mole that itches, bleeds, or crusts. The "ugly duckling" sign—a mole that looks different from your others—also warrants attention.

While the ABCDE criteria focus specifically on evaluating individual moles, there are additional warning signs that should prompt you to seek medical evaluation. Being aware of these signs can help you identify potential problems that might not fit the classic melanoma presentation.

New moles that appear after age 30 deserve special attention. While it's normal to develop new moles during childhood and young adulthood, the development of new moles later in life is less common and should be monitored closely. A new mole isn't automatically cause for alarm, but it should be watched carefully for any changes.

Any mole or skin lesion that changes—whether in size, shape, color, or texture—should be evaluated by a dermatologist. The human body is constantly changing, but moles should remain relatively stable over time. Rapid changes are particularly concerning and warrant prompt medical attention.

Symptoms That Require Immediate Attention

Certain symptoms require prompt medical evaluation and should not wait until your next routine appointment. If you notice a mole that is rapidly growing over a period of weeks, has started bleeding spontaneously (not from trauma), or is associated with a lump that you can feel, contact a dermatologist as soon as possible.

Similarly, if you have a sore that has not healed after three weeks, this warrants evaluation. Non-healing sores can be a sign of both basal cell and squamous cell carcinoma. Don't assume that because a lesion doesn't look like a typical mole, it can't be skin cancer.

Who Is at Higher Risk for Skin Cancer?

Higher risk factors for skin cancer include fair skin that burns easily, a history of sunburns (especially blistering burns), excessive sun exposure or tanning bed use, having many moles (50+), a family or personal history of skin cancer, weakened immune system, and certain genetic conditions.

Understanding your personal risk factors can help you determine how vigilant you need to be with skin self-exams and how often you should see a dermatologist for professional skin checks. While anyone can develop skin cancer, certain factors significantly increase the risk.

Skin type and complexion play a major role in skin cancer risk. People with fair skin, light-colored eyes, and red or blonde hair have less melanin to protect them from UV radiation and are at higher risk. Those who burn easily and tan poorly are particularly vulnerable. However, it's crucial to understand that people with darker skin tones can also develop skin cancer, and melanomas in this population are often diagnosed at later stages because of lower awareness.

Sun exposure history is one of the most significant risk factors. Cumulative sun exposure over a lifetime increases the risk of basal cell and squamous cell carcinomas, while severe, blistering sunburns, particularly during childhood and adolescence, are strongly linked to melanoma development. Tanning bed use also significantly increases skin cancer risk—even one session before age 35 increases melanoma risk by 59%.

Number of moles correlates with melanoma risk. Having more than 50 ordinary moles indicates an increased risk. Additionally, having atypical moles (dysplastic nevi)—moles that are larger than average, have irregular borders, or have varied colors—further increases risk. People with many moles should be particularly diligent about self-exams and professional skin checks.

Family and personal history also matter. If you have a first-degree relative (parent, sibling, or child) who has had melanoma, your risk is significantly higher. Having had skin cancer yourself means you're at increased risk for developing it again. Certain genetic conditions, such as xeroderma pigmentosum, dramatically increase skin cancer risk.

When Should You See a Doctor About a Skin Change?

See a dermatologist if you notice any mole meeting ABCDE criteria, a new mole after age 30, an "ugly duckling" mole that looks different from others, any mole that has changed, a sore that won't heal, or any skin change that concerns you. Don't wait—early detection is critical for successful treatment.

One of the most common questions people have after performing a skin self-exam is whether what they've noticed requires professional evaluation. The general rule is: when in doubt, get it checked out. Dermatologists would rather evaluate a benign lesion than have a patient delay seeking care for something suspicious.

You should definitely schedule an appointment if any of your moles meet one or more of the ABCDE criteria, if you've noticed any mole that has changed in size, shape, color, or sensation, or if you have a mole that looks different from all your other moles (the ugly duckling sign). New growths, sores that don't heal, or any skin change that concerns you are also valid reasons to seek evaluation.

In addition to seeking care for specific concerns, adults should have a professional full-body skin examination at least once a year, even if they haven't noticed any specific problems. This allows a dermatologist to establish a baseline of your skin and identify any areas that might need monitoring. People at higher risk for skin cancer may need more frequent professional examinations.

What to Expect at a Dermatologist Visit

During a skin examination, a dermatologist will systematically examine your entire skin surface, including areas you might have difficulty seeing yourself. They may use a dermatoscope, a special magnifying device with polarized light, to examine suspicious lesions in more detail. Dermoscopy allows dermatologists to see structures beneath the skin's surface that aren't visible to the naked eye.

If the dermatologist identifies a lesion that needs further evaluation, they may recommend a biopsy. A skin biopsy involves removing all or part of the suspicious lesion for microscopic examination by a pathologist. There are several types of biopsies, and the dermatologist will choose the most appropriate method based on the characteristics of the lesion.

How Can You Reduce Your Risk of Skin Cancer?

Reduce your skin cancer risk by seeking shade during peak sun hours (10 AM to 4 PM), wearing protective clothing and wide-brimmed hats, applying broad-spectrum SPF 30+ sunscreen daily and reapplying every 2 hours, avoiding tanning beds, and never intentionally sunbathing.

While regular skin self-exams are crucial for early detection, preventing skin cancer in the first place is even better. The vast majority of skin cancers are caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. This means that skin cancer is largely preventable through consistent sun protection practices.

Seek shade during peak UV hours, typically between 10 AM and 4 PM when the sun's rays are strongest. Remember that UV rays can reflect off surfaces like water, sand, snow, and concrete, increasing your exposure even in the shade. Cloudy days are not safe either—up to 80% of UV rays can penetrate cloud cover.

Wear protective clothing when outdoors. Long-sleeved shirts, long pants, and wide-brimmed hats (with at least a 3-inch brim) provide physical barriers against UV radiation. Darker colors and tightly woven fabrics generally offer more protection. Special UV-protective clothing with an Ultraviolet Protection Factor (UPF) rating is available and provides reliable, consistent protection.

Use sunscreen correctly as part of your daily routine. Choose a broad-spectrum sunscreen with SPF 30 or higher that protects against both UVA and UVB rays. Apply it generously to all exposed skin 15-30 minutes before going outdoors, and reapply every two hours or immediately after swimming or sweating. Don't forget often-missed areas like the ears, neck, tops of feet, and the part in your hair.

Protect your eyes with sunglasses that block 99-100% of UV radiation. The skin around your eyes is delicate and susceptible to skin cancer. Look for sunglasses labeled as blocking UV rays, and choose wraparound styles for additional protection.

Avoid tanning beds completely. Indoor tanning devices emit UV radiation that significantly increases skin cancer risk. There is no such thing as a safe tan from a tanning bed. Many countries have restricted or banned tanning bed use for minors due to the well-documented cancer risk.

Can Technology Help with Skin Self-Exams?

Smartphone apps can help track moles over time by storing photos for comparison, but they cannot diagnose skin cancer. Artificial intelligence-based apps may help flag suspicious lesions, but they are not replacements for professional evaluation. Technology should supplement, not replace, regular self-exams and dermatologist visits.

In recent years, numerous smartphone applications have been developed to help people monitor their skin and track changes in moles. These apps range from simple photo storage systems to sophisticated artificial intelligence-based analysis tools. Understanding what these technologies can and cannot do is important for using them effectively.

Photo documentation apps allow you to take standardized photos of moles and store them in an organized way. By comparing photos over time, you can more easily detect changes that might otherwise be too subtle to remember. Many dermatologists recommend this type of documentation, particularly for patients with many moles or a history of skin cancer.

AI-powered analysis apps use machine learning algorithms trained on thousands of images to evaluate whether a mole appears suspicious. While some of these apps have shown promising results in research studies, they have significant limitations. Studies have found that these apps can miss melanomas and also generate false alarms about benign lesions. The FDA has warned consumers that most skin cancer detection apps have not been properly validated.

The most important thing to understand about any skin analysis technology is that no app can diagnose skin cancer. A definitive diagnosis can only be made through a biopsy and pathological examination. Apps should be viewed as tools that might help you decide when to seek professional evaluation, not as substitutes for medical care.

Are There Special Considerations for Different Groups?

Different groups have unique considerations: people with darker skin tones should check palms, soles, and nails carefully; children need parental help with exams; pregnant women should monitor changing moles; and those with many moles or atypical mole syndrome may need more frequent professional checks.

While the basic principles of skin self-examination apply to everyone, certain groups have special considerations that can affect how they approach skin health and cancer detection.

People with Darker Skin Tones

Although skin cancer is less common in people with darker skin, it is often diagnosed at later stages and has a higher mortality rate in these populations. This disparity is largely due to lower awareness and delayed diagnosis. People with darker skin should pay particular attention to areas with less pigmentation, including the palms of the hands, soles of the feet, and nail beds, where melanoma is more likely to occur. Acral lentiginous melanoma, which develops on the palms, soles, or under nails, is the most common type of melanoma in people with darker skin.

Children and Adolescents

While melanoma is rare in children, it does occur, and children should be taught about sun protection from an early age. Parents should perform skin checks on young children and teach older children and teenagers how to examine their own skin. Adolescence is an important time for establishing sun protection habits that will last a lifetime.

Pregnant Women

Hormonal changes during pregnancy can cause moles to change in size, shape, and color. While most of these changes are benign, pregnant women should monitor their moles carefully and report any significant changes to their healthcare provider. Melanoma during pregnancy is the most common malignancy affecting pregnant women, and early detection remains critical.

People with Atypical Mole Syndrome

Individuals with atypical mole syndrome (also called dysplastic nevus syndrome) have many moles (often 100 or more), many of which are atypical in appearance. These individuals are at significantly higher risk for melanoma and require close surveillance, including more frequent professional skin examinations and often whole-body photography to track changes over time.