Melanoma is the world’s most dangerous type of skin cancer. Of the estimated 192,310 cases that will be diagnosed in the US in 2019, over a third or 69,480 will be invasive and penetrate to the dermis, the skin layer below the epidermis. Over 7200 people in the US die from melanoma per year.
If caught early, melanoma can almost always be treated. Melanoma’s deadliness, however, is due to its propensity for metastasizing or spreading to other parts of the body. Once melanoma has metastasized, it becomes much harder to treat, and the patient’s chances of survival decline markedly.
Doctors describe melanoma as having stages. The higher the number, the more severe the cancer is. Stage 0 melanomas are those that have not spread beyond the epidermis, while Stage I melanomas have reached the dermis. Stage II melanomas are also confined to the dermis, but they are bigger and have other traits that indicate they are about to spread. Stage III melanomas have spread to nearby tissues and Stage IV cancers have spread to different parts of the body.
Doctors use the different stages to help them decide on a treatment. Melanomas in the early stages can be surgically removed, but patients with more advanced cancers will also need treatments like chemotherapy or radiation therapy to kill all of the cancer cells scattered throughout their body.
What Causes Melanoma?
Melanoma is caused by genetic damage to skin cells, and that genetic damage is usually caused by prolonged exposure to ultraviolet radiation, whether from tanning beds or sunlight. The UV radiation causes mutations in the skin cells that result in their rapid multiplication and formation of small tumors. Those tumors originate within the melanocytes, which are pigment-producing cells in the epidermis’ basal layer. A melanoma often looks like a mole and can develop from a mole.
Risk factors that increase a person’s chance of developing melanoma include the following:
- Lots of exposure to the sun or other sources of UV radiation like tanning booths
- Fair skin
- Weakened immune system
- Family history of melanoma
- Having over 50 moles
- Some genetic conditions
People with any of the above risk factors can reduce their chances of developing melanoma by limiting their exposure to the sun and performing monthly self-exams. They should also see their doctor at least twice a year for a full-body skin exam.
The doctor may take pictures of the moles to record any changes in existing moles or the appearance of new moles. A patient with a family history of melanoma should take their children to be examined, for some youngsters in such families can develop melanoma while still in their teens.
What Are The Symptoms of Melanoma?
Broadly speaking, any mole, blemish, lump, or spot that looks different from the others on a patient’s skin should be examined by a doctor. Doctors call such differences “the ugly duckling sign,” and they can indicate cancer.
More specifically, doctors recommend that people follow the ABCDE rule when examining themselves. They also recommend performing a thorough monthly self-exam from head-to-toe and check for anything unusual.
The ABCDE rule is as follows:
A = Asymmetry
B = Border
C = Color
D = Diameter
A normal, non-cancerous mole has two matching halves and a distinct and even border. It is typically brown or black and will be the same shade and color throughout. It is also small and is no more than ¼ inch across, or about the diameter of a pencil eraser. Finally, normal moles don’t change. They stay the same throughout their owner’s lifetime.
By contrast, a cancerous mole is often asymmetrical and has a jagged, irregular, or indistinct border. It can be white, red, or blue, or it can be several different colors. A cancerous mole will often be bigger than a pencil eraser. A melanoma also changes over time: It can turn colors, or it can grow.
Other possible signs of melanoma include the following:
• A sore that won’t heal
• A new swelling or red patch beyond the mole’s border
• Change in a mole’s surface like scaliness, bleeding, oozing, or a new bump
• Change in sensation like pain, tenderness, or itchiness
• Pigment spreading beyond the mole’s border into the surrounding skin
There are four types of melanoma. Three start off as confined to the epidermis, while the fourth is invasive from the start.
The most common type is the superficial spreading melanoma, which occurs in about 70 percent of cases. It is the type most likely to affect young people. While it can develop anywhere on the body, it is most likely to develop on the legs in women, the trunk in men, and the upper back in both sexes. As its name suggests, the superficial spreading melanoma remains confined to the epidermis for a long time before reaching the skin’s deeper layers. The superficial spreading melanoma can develop within a formerly benign mole or appear as a brand-new blemish. Its appearance follows the description of the ABCDE rule: It is asymmetrical, has an irregular border, and can appear in a variety of colors.
The nodular melanoma is the most aggressive type and is typically invasive at the time of diagnosis. It makes up 10 to 15 percent of cases and is found mainly in older patients. It is most commonly found on the arms, legs, or trunk, and men often have it on their scalp. It typically appears as a black bump, but it can be other colors like white, red, blue, brown, tan, or flesh-toned.
Lentigo melanoma resembles the superficial spreading melanoma in appearance, but it is more likely to develop in older patients. It develops on places that have been heavily exposed to the sun, such as the face, arms, ears, and upper trunk. The invasive form of lentigo melanoma is sometimes called lentigo maligna melanoma. Lentigo melanoma is the most common melanoma in Hawaii.
Acral lentiginous melanoma differs from the other types in that it often occurs in people with dark skin, like African-Americans and Asians. By contrast, it is less common in Caucasians. It appears mainly as brown or black spots on the palms, the soles of the feet, or under the nails. It progresses more quickly than do superficial spreading melanoma or lentigo melanoma, and it is often detected at a later stage.