In short. Skin cancer screening is a structured whole-body examination with dermoscopy, aimed at finding basal cell carcinoma, squamous cell carcinoma and melanoma while they are small. It is offered to people with defined risk factors, not the whole population; everyone else is served by monthly self-examination and prompt review of a changing lesion. Tissue, not observation, settles a suspicious lesion.
Key points
- Screening targets people with defined risk factors; everyone else relies on monthly self-examination.
- Risk factors: fair skin, blistering sunburns, heavy sun exposure, tanning beds, prior skin cancer, family history, atypical moles, immunosuppression.
- In darker skin melanoma often appears on palms, soles and nails, which self-checks should include.
- ABCDE covers asymmetry, border, colour, diameter over six millimetres and evolution.
- Evolving is the most important sign; a suspicious lesion is biopsied, not watched.
Skin cancer is the one cancer visible on the surface. The three common forms behave differently: basal cell carcinoma, the most common, is slow-growing and locally destructive; squamous cell carcinoma is sun-driven and can spread if neglected; melanoma is the least common and the most serious, though highly curable when caught early. A screening visit is a trained look over the whole skin, with dermoscopy, aimed at catching lesions while they are small and simple to treat.
What screening involves
A screening visit is a structured whole-body examination, not a glance at one spot. It includes the scalp, between the toes and under the nails, with dermatoscopy of any suspicious lesion. Where there are many lesions, photography or mole mapping records them, so that change is documented rather than remembered. Self-examination between visits follows the same discipline: the same mirror and the same light, once a month, with a partner or a phone camera for the back.
Who needs regular screening rather than self-check?
Regular checks are for fair, sun-sensitive skin with a history of blistering sunburns; heavy cumulative sun exposure or an outdoor occupation; tanning bed use; a personal history of skin cancer or precancerous spots; a family history of melanoma; many or atypical moles; and immunosuppression after organ transplant or with certain medications. In darker skin tones, melanoma more often appears on the palms, soles and nails, sites that a self-check should include.
Outside those groups, the practical route is monthly self-examination with prompt review of anything new or changing, rather than a whole-body examination for everyone.
| Screening visit | Self-examination | |
|---|---|---|
| Who it is for | People with the risk factors above | Everyone, and the same groups between visits |
| What is examined | The whole skin, including scalp, between toes and under nails | The same areas, with a partner or phone camera for the back |
| What is used | Dermoscopy, and photography or mole mapping where needed | The same mirror and the same light |
| How often | At an interval set at the visit | Once a month |
| What it can do | Document change and sample suspicious lesions | Notice a new or changing lesion early |
| What it cannot do | Replace tissue diagnosis | Replace dermoscopy or a trained examination |
| What happens next | Biopsy, or a review interval | Prompt review if anything is new or changing |
The warning signs: ABCDE and beyond
- A, asymmetry: one half unlike the other.
- B, border: edges irregular, notched or blurred.
- C, colour: varied shades within one lesion.
- D, diameter: larger than about six millimetres, though small melanomas exist.
- E, evolving: any change in size, shape, colour or symptoms, the single most important sign.
Beyond moles, three patterns matter. A pearly bump with visible vessels, or a sore that heals and returns, suggests basal cell carcinoma. A scaly, crusted or horny growth on sun-damaged skin suggests squamous cell carcinoma or a precancerous spot. A dark streak in a nail, or pigment spreading from a mole onto the surrounding skin, also needs review.
What happens to a lesion that looks suspicious?
No scan, app or eyeball replaces tissue. A suspicious lesion is sampled, usually with a small shave or punch biopsy under local anaesthetic, and examined under the microscope. The result settles the plan: nothing further, complete removal, staged removal with margin mapping for certain tumours, or onward referral. Suspicious lesions are biopsied, not lasered, not frozen without thought, and not watched for long.
Treatment when something is found
Precancerous spots, actinic keratoses, are field-treated with cryotherapy, topical regimens or light-based therapy. Basal and squamous cell carcinomas are removed with margin control. Melanoma is removed with margins scaled to its measured depth, with lymph-node assessment for deeper lesions. Early lesions are office surgery; neglected lesions become major surgery. The difference is almost entirely timing.
When should you arrange review without waiting?
- Any lesion is changing, bleeding without cause, or failing to heal within a few weeks.
- A new dark streak appears in a nail, or pigment spreads from a mole onto the surrounding skin.
- You carry the risk factors above and have never had a baseline whole-body skin check.
Sources
- NICE: guidance on recognition and referral of suspected skin cancer
- British Association of Dermatologists: patient information on skin cancer
- Cancer Research UK: information on skin cancer signs and skin checks
Internal links
Frequently asked questions
Who should have regular skin checks?
Fair sun-sensitive skin with blistering sunburns, heavy cumulative sun exposure, tanning bed use, a personal or family history of skin cancer, many or atypical moles, and immunosuppression. In darker skin tones melanoma more often appears on palms, soles and nails.
What are the warning signs of skin cancer?
The ABCDE rules: asymmetry, an irregular or notched border, several colours in one lesion, a diameter over about six millimetres, and any evolution in size, shape, colour or symptoms. Evolving is the single most important sign, along with a sore that heals and returns.
How is skin cancer actually diagnosed?
No scan, app or eyeball replaces tissue. A suspicious lesion is sampled, usually with a small shave or punch biopsy under local anaesthetic, and examined under the microscope. The result settles the plan, which is why suspicious lesions are biopsied rather than lasered or watched.
Risks & Limitations
- Most chronic skin disease is managed rather than cured, and relapse is expected.
- Treatments typically need 8–12 weeks before response can be judged fairly.
- Topical treatment can cause irritation, dryness, peeling and photosensitivity.
- Systemic therapy may require blood monitoring and carries organ, metabolic and pregnancy risks.
- Isotretinoin in particular requires strict monitoring and pregnancy prevention.
- Pigment change is often slow and may be incomplete.
- No treatment works for everyone, and response cannot be predicted with certainty.
When to Seek Care
- A mole or lesion that changes in size, shape or colour, or starts to bleed, itch or crust.
- Fever with a widespread rash, blistering, or rash involving the eyes, mouth or genitals — seek emergency care.
- Rapidly spreading redness, swelling or pain in the skin.
- Facial swelling or difficulty breathing — possible severe reaction; seek emergency care immediately.
- New or worsening symptoms while taking a monitored medication.
References & Further Reading
- American Academy of Dermatology (AAD) — public and clinical guidance
- World Health Organization (WHO) — skin and infectious disease resources
- Chinese Medical Association, Dermatology Branch — clinical guidance
- Cochrane Library — systematic reviews in dermatology
This page is patient education, not medical advice, and it does not cite individual studies. Discuss your own case with a qualified clinician. To arrange an assessment at Chongqing West District Hospital, see Contact & Consultation.