Skin cancer is the most common cancer in the US. May is Skin Cancer Awareness Month, which is an ideal time to remind ourselves how much early detection and sun protection matter. Most skin cancers are highly treatable when found early, yet many people overlook subtle warning signs. Routine self-checks and periodic professional skin exams can make a meaningful difference in catching problems before they become serious.
What causes skin cancer?
Skin cancer develops when DNA inside skin cells becomes damaged and the cells begin to grow out of control. The most common cause is ultraviolet (UV) radiation from the sun or from indoor tanning devices. UV rays damage skin cells even on cloudy days, and the harm accumulates over time. Both blistering sunburns and chronic sun exposure increase risk. Tanning beds expose users to concentrated UV radiation, which raises the risk of all major skin cancers.Other factors can contribute as well. These factors include:
- A weakened immune system – Due to medical conditions or medications which lower immunity, such as medications given to organ transplant recipients.
- Family history,
- Fair skin that burns easily,
- Numerous or atypical moles,
- Older age,
- Less common factors include exposure to substances like arsenic, prior radiation exposure, and certain rare genetic conditions.
Remember that skin cancer can occur in anyone, regardless of skin tone or other factors, even though those with risk factors are more likely to develop skin cancer.
What types of skin cancer occur?
The most common types are basal cell carcinoma and squamous cell carcinoma, which arise from the mid to outer layers of the skin.
Melanoma, though less common, is the most dangerous because it can spread quickly if not detected early. Melanoma develops in the cells that make melanin (skin pigment).
What should I look for on my skin?
One of the most effective tools for early detection is the ABCDE rule, which helps you evaluate moles or spots that may be concerning. These features are especially important for identifying melanoma:
- A – Asymmetry: One half of the mole does not match the other.
- B – Border: Edges are irregular, notched, or scalloped.
- C – Color: Uneven color with multiple shades of brown, black, tan, or even red, white, or blue.
- D – Diameter: Larger than 1/4 inch (about the size of a pencil eraser), though melanomas can be smaller.
- E – Evolving: Any change in size, shape, color, or symptoms such as itching, bleeding, or non-healing areas.
Dermatologists also emphasize watching for the “ugly duckling”, which is a mole that looks different from your others. If something stands out, it’s worth getting checked.
How can I reduce my risk?
Limit midday sun, wear protective clothing, and use broad-spectrum sunscreen. Avoid tanning beds entirely. Regular self-exams and professional skin checks help catch changes early, when treatment is most effective.
This month is an ideal time to commit to protecting your skin and to make skin checks a lifelong habit.
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Dr. Anita Bennett MD – Health Tip Content Editor