Know Your Enemy: A Guide to the Different Types of Skin Cancer

Skin cancer is the most commonly diagnosed cancer in the United States, with millions of new cases identified each year. Yet despite how prevalent it is, many people don't realize that "skin cancer" is not a single disease, it's an umbrella term that covers several distinct conditions, each with its own behavior, appearance, risk profile, and treatment approach. Understanding the differences can help you recognize warning signs earlier and have more informed conversations with your dermatologist.

Basal Cell Carcinoma

Basal cell carcinoma, or BCC, is the most common form of skin cancer, accounting for the majority of all skin cancer diagnoses. It arises from the basal cells, the deepest layer of the epidermis, and is almost always caused by cumulative UV exposure over a lifetime. This is why BCCs are most frequently found on sun-exposed areas like the face, nose, ears, scalp, and neck, though they can appear anywhere on the body.

BCC tends to grow slowly and rarely spreads to other parts of the body. However, that doesn't mean it should be ignored. Left untreated, basal cell carcinomas can invade surrounding tissue, including cartilage and bone, causing significant local damage that becomes increasingly difficult to treat.

In terms of appearance, BCCs are variable. They may present as a pearly or waxy bump, a flat flesh-colored or slightly pink patch, a sore that heals and then reopens, or a pink growth with raised edges. If you notice something on your skin that looks unusual and simply won't go away, it warrants a professional evaluation.

Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) is the second most common skin cancer. It develops from the squamous cells that make up most of the outer layer of the skin, and like BCC, it is strongly associated with UV radiation. People who have had significant sun exposure, used tanning beds, or experienced prior sunburns carry elevated risk. SCCs also arise more frequently in areas of chronic skin injury, such as old scars, burn sites, or wounds that don't heal properly.

SCC typically appears as a firm, red nodule, a flat lesion with a crusted or scaly surface, or a new sore in an old scar. On the lips, it can look like a persistent rough patch; under the nails, it may appear as a discolored or lifted area of the nail bed.

Unlike basal cell carcinoma, SCC carries a meaningful, though still relatively low, risk of metastasis, meaning it can spread to lymph nodes and other organs if not treated. The risk of spreading increases with larger tumors, tumors located on the lips or ears, and cases in immunocompromised patients. Early treatment is critical and highly effective.

Melanoma

Melanoma is the least common of the three main skin cancer types, but it is by far the most serious. It develops in the melanocytes, the cells responsible for producing the pigment melanin, and has a significantly higher tendency to spread to other organs than either BCC or SCC. When melanoma is caught early and confined to the outer layers of skin, it is highly treatable. When it advances to distant organs, outcomes become considerably more difficult to manage.

Melanoma often appears as a new mole or as a change in an existing mole. Dermatologists use the ABCDE criteria as a guide for what to watch for: Asymmetry (one half doesn't match the other), Border irregularity (ragged, uneven, or blurred edges), Color variation (shades of brown, black, red, white, or blue within the same lesion), Diameter larger than about 6 millimeters, and Evolution (any change in size, shape, color, or any new symptom like bleeding or itching).

Some melanomas don't follow this pattern, amelanotic melanomas, for instance, have little to no pigment and may look pink, red, or skin-colored, making them especially easy to miss. This is one reason why routine professional skin exams are valuable even when you've been diligent about self-checks.

Merkel Cell Carcinoma

Merkel cell carcinoma is a rare but aggressive form of skin cancer that develops in Merkel cells, which are found near the nerve endings in the skin and play a role in the sense of touch. Because it is so uncommon, many people are unfamiliar with it.

MCC typically appears as a flesh-colored or bluish-red nodule, often on the face, head, or neck. It tends to grow quickly and has a higher likelihood of spreading than either BCC or SCC. Risk factors include older age, significant sun exposure, a weakened immune system, and infection with a common virus called Merkel cell polyomavirus, which appears to play a role in many cases.

Because MCC is often mistaken for a cyst, benign growth, or other less serious condition, diagnosis is frequently delayed. Any rapidly growing, unusual nodule on the skin should be evaluated by a dermatologist promptly.

What All Skin Cancers Have in Common

Despite their differences, all types of skin cancer share one important characteristic: they are most treatable when caught early. The earlier a skin cancer is identified and properly diagnosed, the simpler and more effective the treatment options tend to be, and the lower the risk of complications, scarring, or spread.

Regular self-examination is a valuable habit, but it's no substitute for a professional full-body skin check. A board-certified dermatologist is trained to identify subtle changes and atypical presentations that are easy to overlook on your own.

Schedule Your Skin Check at Specialists in Dermatology

At Specialists in Dermatology, our team has extensive experience diagnosing and treating all forms of skin cancer, from the most common to the most complex. Whether you've noticed a suspicious spot or simply want the peace of mind that comes with a thorough professional evaluation, we're here to help. Don't wait for something to look obviously wrong, the lesions most worth catching are often the ones that look unremarkable at first glance.

Reach out to our office at (520) 382-3330 or click the book now button to schedule your skin cancer screening today.