You notice a spot on your skin, maybe it has been there for months, maybe it just appeared, but your gut tells you it might be worth checking out. Is this something to panic about or is this just a normal part of your skin? The truth is, it depends. Not all skin cancers are the same. There are three main types of skin cancers, basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma. Understanding the differences between them, including the cells these cancers originate from and the rate they spread, require different screening strategies and treatment.

This article breaks down each type of skin cancer, how screening differs, why these differences matter and what action needs to be taken.

Types of Skin Cancer

Basal Cell Carcinoma

BCC is the most common malignancy globally. 1 in 5 Americans will develop BCC during their lifetime and it accounts for approximately 75% of all skin cancer cases, making it far more prevalent than people realise.

BCC originates in the basal cells, the foundation layer at the bottom of the skin's epidermis. Normally, these cells are constantly dividing to create new skin cells, pushing upward to the skin surface and eventually die and flake off. In BCC, the basal cells mutate, grow slowly and usually stay put. BCC almost never spreads to other parts of the body. Its 5-year survival rate is at 100%, meaning those diagnosed with BCC, are just as likely to be alive five years later as someone without BCC.

BCC varies in appearance. It can appear as a shiny, pearly bump (sometimes with visible blood vessels), a scaly patch or a non-healing sore that bleeds and crusts over. It typically appears on sun-exposed areas such as the face, neck, ears and shoulders.

The clinical significance: BCC is serious because of how common it is and its cosmetic impact, not because it is life-threatening. Most BCCs are cured with straightforward treatments.

Squamous Cell Carcinoma

SCC is the second most common skin cancer, accounting for 20-25% of all non-melanoma skin cancers. Unlike BCC, SCC grows faster and has a slightly higher risk of spreading, though most cases are still highly curable.

SCC originates in the squamous cells, which form the upper layers of the epidermis. These cells produce keratin (the protein in your skin and nails) and normally become the dead outer layer that sheds daily. 95% of squamous cell carcinomas can be cured if treated early, but without early treatment, SCC spreads more readily than BCC. When SCC spreads, it can involve lymph nodes or distant organs, which complicates treatment and worsens outcomes.

SCC typically appears as a rough, scaly bump or patch, a crusty sore or a spot that bleeds easily. It usually occurs on sun-exposed areas such as the scalp, ears, face, hands, arms and legs.

The clinical significance: SCC is the intermediate threat. It is more aggressive than BCC but still highly curable when caught early on, which makes regular screening important.

Melanoma

Melanoma is the least common form of skin cancer, representing only 1-2% of all skin cancer cases. It is also the most dangerous. Melanoma is responsible for the vast majority of skin cancer deaths, despite being far less common than BCC or SCC. Melanoma originates in melanocytes, the pigment-producing cells that give your skin colour and UV protection and can spread throughout the body quite aggressively.

The survival disparity is staggering. When caught early, before spreading to the inner dermis, melanoma has a 98-99% five-year survival rate. Once melanoma spreads to distant parts of the body, that plummets to 15-35%. That is a difference of 50-84% points and why early detection is important.

Melanoma varies dramatically in appearance. Unlike BCC or SCC, which have relatively consistent presentations, melanoma can look like almost anything: a new mole, a changing mole, an asymmetrical spot, a dark patch or even a non-pigmented lesion. This variability is what makes it tricky to spot.

The clinical significance: Melanoma is a true medical emergency when it concerns timing. Any suspicious lesion requires rapid dermatological evaluation.

Figure 1: BCC dominates in sheer numbers (75% of cases), while melanoma, despite being only 1-2% of cases, accounts for the majority of skin cancer deaths.

The chart above illustrates a crucial paradox: prevalence does not equal severity. BCC is approximately 75 times more common than melanoma, yet melanoma has led to more deaths. This is because melanoma's ability to spread changes the entire clinical picture. The statistics show:

• 5.4 million cases of BCC and SCC are diagnosed annually in the United States
• There were approximately 112,000 cases of melanoma in 2026
• Melanoma led to roughly 8,510 deaths in 2026
• Fewer than 1% of skin cancer deaths are from BCC or SCC

For most people, BCC and SCC are common but highly treatable, however, for melanoma, early detection can drastically change the survival rate.

Risk Factors

Some people are at a higher risk of skin cancer and require different screening intensities than others.

High Risk  - annual and more frequent screening:

• Familial atypical multiple mole melanoma syndrome (FAMMM) is a hereditary condition that significantly elevates melanoma risk and screening is recommended every 3 months
• Multiple atypical moles (dysplastic nevi) are irregular moles with mixed colours and the larger size are the single strongest risk factors
• Family history of melanoma where two or more close relatives with melanoma substantially increase the risk of skin cancer
• Personal history of melanoma significantly increases the risk of new melanomas
• Immunosuppression such as transplant recipients and those with weakened immune systems face elevated risk

Intermediate risk - annual screening:

• Fair skin, light hair, light eyes
• Extensive sun exposure history
• History of severe sunburns
• Multiple regular moles

Lower risk - self-exams, dermatology visit if concerned:

• Darker skin type
• No family history of melanoma
• Limited sun exposure history
• Few moles

Even people at lower risk can develop melanoma, so the safest approach is to have monthly self-examinations and reporting any new or changing lesions to a dermatologist.

Screening For Skin Cancer

There are many ways to screen and diagnose skin cancer and can differ for each type of skin cancer. If you see any irregular changes to your skin, a dermatologist can make a diagnosis.

Visual Examination

A visual examination by the dermatologist is remarkably accurate for both BCC and SCC. They can visually examine the irregularity using a dermoscope. Experienced dermatologists can diagnose BCC with 95% accuracy from visual examination alone whilst SCC has a 62% accuracy. Visual examination to diagnose melanoma is less reliable because of its varied appearance where melanoma can mimic benign moles effectively. This is where the ABCDE rule comes in.

The ABCDE Rule

The ABCDE rule is a framework that patients, family members and doctors use to identify potentially dangerous moles. If a spot shows two or more of these characteristics, it warrants dermatological evaluation:

• A - Asymmetry: One half of the spot differs from the other half. A normal mole is symmetrical and when drawing a line through the middle, both halves match. Melanomas often have asymmetrical halves
• B - Border Irregularity: The edges are jagged, scalloped or poorly defined. Normal moles have smooth, well-defined borders
• C - Colour Variation: Multiple colours appear within the same lesion. Look for brown, black, tan, white, red or blue areas within a single mole
• D - Diameter: The mole is larger than 6 mm (roughly the size of a pencil eraser)
• E - Evolving: The spot is changing in size, shape or colour over time

Important caveat: Early melanomas do not always tick all these boxes so the ABCDE rule is helpful but imperfect. A mole that looks different from your other moles is also equally important and sometimes easier for patients to recognise.

Dermoscopy

Dermoscopy uses a handheld tool called a dermatoscope that magnifies skin lesions 10-100 times. The dermatologist holds the device against your skin and looks at subsurface structures invisible to the naked eye.

Dermoscopy dramatically improves diagnostic accuracy:

• For BCC, dermoscopy achieves 97% sensitivity, meaning it catches nearly all BCCs
• For SCC, dermoscopy helps distinguish SCC from BCC by revealing different structural patterns
• For melanoma, dermoscopy achieves 94.6% sensitivity and 85.5% specificity

Figure 2: Dermoscopy improves diagnostic accuracy across all three skin cancer types, particularly benefiting less experienced dermatologists.

Dermoscopy is not essential for BCC since the visual exam is already very accurate, but it significantly improves SCC and melanoma detection and diagnosis.

Digital Dermoscopy and Sequential Monitoring

Dermatology is now increasingly using digital dermoscopy, which captures high-resolution images of lesions and compares them over time. This technology detects subtle changes that might be missed during routine exams and is particularly valuable for patients with high nevus count (many moles) or atypical mole syndrome.

Skin Biopsy

A diagnosis can also be made by carrying out a biopsy on a suspicious lesion. A dermatologist removes a small tissue sample and sends it to a pathologist who examines it under a microscope to provide a definitive diagnosis. The procedure takes about 15 minutes. The area is cleaned, local anaesthetic can be injected and the dermatologist removes tissue via a punch biopsy or shave biopsy and the wound is bandaged. Results arrive within a few days to a week.

Biopsy is necessary when:

• Clinical examination suggests possible skin cancer
• A spot is changing or concerning despite its benign appearance
• Diagnosis is unclear after dermoscopy
• Treatment decisions require knowing the exact diagnosis

Advanced Imaging for High-Risk Melanoma

For patients with advanced melanoma (Stage III or IV), regular imaging is essential to detect systemic disease:

• PET-CT scanning is preferred for detecting distant metastases
• Brain MRI is recommended given melanoma's propensity to spread to the brain
• Surveillance intervals - biannual visits are recommended for high-risk patients

Self-Examination

Regular self-examination is low-cost, accessible and potentially life-saving. For people previously treated for melanoma, monthly self-exams provide 63% reduction in mortality compared to those who do not self-examine.

Figure 3: Patients who detect their own melanoma recurrences have 63% lower mortality compared to those who do not perform self-examinations, underscoring the life-saving potential of regular self-monitoring.

How to self-examine:

• Stand in front of a full-length mirror in a well-lit room
• Check your entire body systematically from top to bottom
• Do not forget hidden areas such as the scalp, behind ears, back, buttocks, soles of the feet, between the toes and the palms
• Have a partner check hard-to-reach areas like your back
• Use a ruler or reference object to estimate lesion size
• Note the colour, shape and any asymmetry
• Document changes month to month (take photos if helpful)
• Perform this monthly on the same day (e.g. the first of each month)

What to document:

• Size of moles
• Shape and symmetry
• Colour and colour variations
• Surface characteristics (smooth, scaly, rough)
• Symptoms (itching, bleeding, tenderness)

When to see a dermatologist immediately:

• Any new mole or spot
• Any mole that looks different from your others
• Any change in a size, shape or colour
• Bleeding, itching or tenderness of a mole
• Any lesion showing two or more ABCDE features
• Any non-healing sore

Special Considerations

Screening Frequency by Type

BCC and SCC screening:

• Self-examination - monthly or as desired (less critical than for melanoma)
• Professional screening - anyone with risk factors should see a dermatologist annually and those with extensive personal history may need more frequent visits

Melanoma screening:

• Self-examination - monthly
• Professional screening - annually, every 6-12 months for those with risk factors or every 3 months for high-risk patients (FAMMM)
• Advanced imaging - digital dermoscopy with sequential monitoring recommended for high-risk patients

Practical Guidance: When to Seek Medical Attention

Urgent consultation - same day or next available appointment:

• Any lesion showing ABCDE features
• Any new mole in an adult (moles typically do not appear after age 40)
• Rapid change in a mole's size, shape or colour
• Bleeding, oozing or itching of a mole
• Any mole that looks different from your others

Non-urgent consultation- within a few weeks:

• Concern about BCC or SCC characteristics
• Desire for professional skin screening as preventive care
• Cosmetic concerns about existing lesions

What to do:

1. Call your primary care doctor for a referral to a board-certified dermatologist
2. If you have risk factors (family history, atypical moles), establish care with a dermatologist proactively, do not wait for a concerning lesion
3. If you notice something suspicious, call to schedule the next available appointment

Prevention

Severe sunburns before the age of 25 is associated with an increased risk of skin cancer. Furthermore, over 90% of melanomas result from UV exposure. So the risk of skin cancer can be reduced by protecting yourself from the sun. This includes:

• Use broad-spectrum sunscreen with SPF 30 or higher on all exposed skin
• Reapply sunscreen every two hours, or more frequently if swimming or sweating
• Seek shade during peak UV hours (10am-4pm daylight time)
• Wear protective clothing such as long sleeves, long trousers and wide-brimmed hats
• Avoid indoor tanning beds
• Protect yourself year-round. UV rays bounce off snow, water and sand

The Survival Impact of Early Detection

Early detection transforms prognosis for all three types of skin cancer especially for melanoma.

Figure 4: The stage at which cancer is detected dramatically affects survival. For melanoma, catching it in the epidermis (Stage 0) yields 97% survival, while metastatic melanoma drops to 30% survival; a 67% point difference.

Basal Cell Carcinoma:

• 100% five-year survival rate regardless of stage
• Early detection ensures better cosmetic outcomes

Squamous Cell Carcinoma:

• 95% five-year survival rate with early treatment
• Prognosis worsens if caught after spreading to lymph nodes

Melanoma:

• Stage 0 (in-situ, confined to epidermis) - 97-99% five-year survival
• Localised stage - 94% survival
• Regional stage (spread to nearby lymph nodes) - 62% survival
• Metastatic - 15-35% survival

Early detection is key in having a strong prognosis where the patient can avoid aggressive chemotherapy, immunotherapy, palliative care or death.

Melanoma Incidence and Mortality Trends

Melanoma incidence has been rising slightly (1.1% per year from 2014-2023), but mortality has been falling significantly (2.2% per year from 2015-2024).

Figure 5: While melanoma incidence has increased, mortality has declined substantially, reflecting improvements in early detection and new systemic treatments.

The reason why there is an increased survival rate despite rising incidence is due to a combination of better education about sun protection and self-examination, more frequent screening and improved treatments such as targeted therapies and immunotherapy.

Furthermore, the person who provides the melanoma diagnosis affects the outcome. Dermatologists provide 3-5% better survival outcomes compared to non-dermatologists, even when detected at the same stage. This reflects dermatologists' expertise in subtle features and their skill with dermoscopy.

Figure 6: Detection by dermatologists yields better survival outcomes at all follow-up periods compared to detection by primary care physicians, underscoring the value of specialist evaluation.

If you are concerned about a skin lesion, seeing a board-certified dermatologist and not only your primary care doctor for evaluation is worth the additional step.

Putting It Together: A Screening Strategy for Life

For most people, a sensible skin cancer screening approach involves three elements:

Element 1: Self-knowledge

• Understand your personal risk factors (skin type, family history, sun exposure history)
• Adjust your prevention and screening intensity accordingly
• Learn the ABCDE rule

Element 2: Home monitoring

• Perform monthly skin self-examination
• Use photos to track changes over time
• Report any concerning changes promptly to a dermatologist

Element 3: Professional screening

• See a board-certified dermatologist for baseline skin examination
• Establish a screening schedule based on your risk
• Advocate for dermoscopy and digital monitoring if available

BCC is common but almost never life-threatening. SCC is intermediate in aggression but highly curable especially when caught early. Melanoma is rare but catastrophic once it becomes advanced. There is a 3-5% survival advantage by seeing a dermatologist rather than a generalist.

Early detection key for treating melanoma whilst early detection for BCC and SCC ensures better cosmetic outcomes and simpler treatment as well as an excellent survival rate. Minor lesions are not a cause for concern but if any changes occur or something does not seem right, regular self-examination and professional screening can help detect skin cancer.

Key Takeaways

• BCC accounts for 75% of skin cancers and has 100% five-year survival. It is common but not life-threatening
• SCC accounts for 20-25% of nonmelanoma skin cancers and has 95% five-year survival. It is more aggressive than BCC but still highly curable early
• Melanoma accounts for only 1-2% of skin cancers but the majority of skin cancer deaths. Late diagnosis changes survival from 98% to 15%
• Early detection of melanoma can improve survival by 50-84%
• Over 90% of melanomas are preventable through sun protection
• Monthly self-examination plus annual professional screening is the best approach for early detection
• See a board-certified dermatologist immediately for any new, changing or suspicious lesions

Further Reading

Understanding Skin Cancer Types

• Skin Cancer Screening and Prevention Guidelines from the National Cancer Institute
• What You Should Know About Basal Cell Carcinoma from Mayo Clinic
• Squamous Cell Carcinoma Overview from Cleveland Clinic
• Melanoma Symptoms and Risk Factors from the NHS

Screening and Detection Methods

• How Skin Cancer Screening Works from Cleveland Clinic
• Skin Biopsy Procedures Explained from Mayo Clinic
• Dermoscopy for Skin Cancer Diagnosis from the American Academy of Dermatology
• ABCDEs of Melanoma and Self-Examination Guide from AAD

Prevention and Risk Management

• Sun Protection and Skin Cancer Prevention from the CDC
• Melanoma Risk Factors and Prevention from the National Cancer Institute
• Atypical Moles and Melanoma Risk from the NCI
• Family History and Hereditary Melanoma Risk from NIH

Surveillance and Follow-Up Care

• Melanoma Surveillance Recommendations for High-Risk Patients
• Digital Dermoscopy Monitoring for Multiple Atypical Moles from PubMed
• Self-Examination Benefits for Melanoma Survivors from Harvard Health
• US Preventive Services Task Force Skin Cancer Screening Recommendation