Skin cancer is the most common cancer in the U.S. and worldwide, and nearly 1 in 5 Americans will develop it by age 70. Because early detection is so important, knowing what to look for on your skin—and when to seek expert care—can make a lifesaving difference.
The Skin Cancer Foundation emphasizes that catching skin cancer early can allow for very effective treatment. Many skin cancers begin as small, subtle changes—new spots, nonhealing areas, or changes in existing moles. Regular self-exams and professional skin checks help ensure that these changes are noticed and evaluated promptly.
Warning signs to look out for
General signs that deserve attention
Clinicians often recommend watching for:
- Any new spot or growth on the skin that looks different from others
- A sore that does not heal within a few weeks
- A spot that itches, crusts, bleeds, or becomes painful
- An existing mole or spot that changes in size, shape, or color
If you see any of these changes, schedule an evaluation with a dermatologist or other qualified clinician as soon as possible.
Suspicious moles
Many clinicians use easy-to-remember patterns to help patients know when a mole or dark spot might be concerning. Features that may be worrisome include:
- Uneven or asymmetric shape
- Irregular or poorly defined borders
- Multiple colors or very dark color
- Diameter larger than a common pencil eraser
- Any mole that is evolving—changing in size, shape, color, or sensation
These patterns are not a diagnosis, but they are important signals to get checked by a professional.
How to perform a skin self-exam
The Skin Cancer Foundation recommends examining your skin from head to toe every month. This habit helps you recognize what’s normal for you and spot changes early.
Step-by-step self-exam
- Use a full-length mirror and a handheld mirror in a well-lit room
- Start with your face, including nose, lips, mouth, and ears (front and back)
- Check your scalp by parting your hair in sections; ask for help if possible
- Examine your hands, including palms, backs, between fingers, and under nails
- Move up your arms, including wrists, forearms, elbows, and upper arms
- Look at your neck, chest, and torso; women should check the skin under the breasts
- Use mirrors to inspect your back, shoulders, and the backs of your arms
- Examine your buttocks, genital area, and the backs of your legs
- Check the fronts of your legs, ankles, tops and soles of your feet, between toes, and under toenails
If you find a spot that worries you, take a photo so you can track changes and contact a clinician for an exam.
When to see a specialist
The Skin Cancer Foundation advises seeing a dermatologist at least once a year for a professional skin exam. You may need more frequent visits if you have a history of skin cancer, many moles, very fair skin, a history of blistering sunburns, or other risk factors. Regular exams complement self-checks and help ensure early detection and timely treatment.
Expert surgical care at WashU Medicine
When a suspicious lesion is identified, expert evaluation and treatment are essential. Surgeons in the Department of Surgery at WashU Medicine are skilled in diagnosing and treating the full spectrum of skin cancers, including basal cell carcinoma, squamous cell carcinoma, and melanoma. Working closely with dermatologists and oncology specialists, they:
- Perform precise biopsies to determine whether a lesion is cancerous and what type it is
- Use advanced surgical techniques tailored to the tumor’s size, depth, and location, with a focus on complete removal while preserving function and appearance
- Provide comprehensive follow-up care, including surveillance for recurrence and guidance on prevention and early detection
This collaborative, multidisciplinary approach ensures that if your self-exam or dermatologist visit uncovers a concerning spot, you have access to high-level, evidence-based surgical care right away. By combining expert treatment with the Skin Cancer Foundation’s prevention and early-detection strategies—sun protection, regular self-exams, and yearly professional skin checks—you can take proactive steps to protect your skin health over the long term.