Definition and Overview
Melanoma and other skin cancers such as basal cell and squamous cell are serious diseases typically caused by excessive exposure to ultraviolet (UV) rays from the sun. Early symptoms include abnormal moles, sores, pigmentation, redness, itching, tenderness, and pain, among others. While some skin cancers may be easier to treat, others, such as malignant melanoma, can be more complicated because of its tendency to spread easily all over the body.
Melanoma is considered as the deadliest skin condition and is responsible for the majority of skin cancer-related deaths.
Causes of Condition
Exposure to ultraviolet rays is the foremost cause of melanoma and other skin cancers. A person who is frequently exposed to intense sunlight for a prolonged period faces the greatest risk of developing various skin conditions. Another common is the use of indoor tanning devices, which have become quite common in recent times.
Additionally, there are other risk factors that make a person more likely to develop melanoma. These include:
- Eye color
- Hair color
- Skin type
- Presence of freckles
- Presence of large birthmarks (more than 8 inches in diameter)
- Presence of atypical moles or dysplastic nevi
- Treatment procedures that involve chemical radiation exposure, such as chemotherapy
- Autoimmune disorders, such as AIDS and rheumatoid arthritis
- Existing medical conditions - Patients suffering from HPV or human papillomavirus, non-Hodgkin’s lymphoma, or endometriosis, among others, face a higher risk of developing skin conditions because these diseases have common risk factors as skin cancers.
How Melanomas Develop
Some studies show that up to 50% of patients suffering from advanced-stage melanoma has a common genetic mutation, specifically called BRAF. Also, people with a family history of melanoma have twice the risk of developing the condition. This supports theories that there's a link between the disease and heredity.
Melanoma often begins to develop in the melanocytes, which is the layer of cells located between the epidermis and dermis. This produces melanin or the skin pigment responsible for determining the color of a person’s skin and hair and protects the skin from the damaging ultraviolet rays released by the sun.
Unfortunately, due to the above risk factors, the melanocytes begin to spread or form in large clusters that become visible on the surface of the skin. These cell proliferations then begin to form moles as well as sun and liver spots. If the melanocytes grow too big, they can reach downwards into the dermis, where they can easily affect the blood vessels and lymphatic system. If this occurs, the affected cells can easily spread to other parts of the body, causing malignant melanoma.
How Other Skin Cancers Develop
Basal cell cancer - Basal cell cancer is a less serious but very common form of skin cancer. It is easier to treat and thus have significantly lower fatality rate. It is also the least likely to spread to the lymphatic system. This skin cancer affects the rounded cells found in the bottommost layer of the epidermis called the basal cell. While they usually grow slowly, there are some aggressive forms that should be treated immediately; otherwise, there is a risk of skin disfigurement.
Squamous cell cancer - Also known as Bowen’s disease, a squamous cell cancer is one of the least common types of skin cancer. It typically develops from keratinocytes, which are flat skin cells located just under the upper layer of the epidermis. Due to their location, there is a risk, albeit minimal, of a squamous cell cancer spreading to the lymph system. More common among men of Asian and African-American descent, this type of skin cancer can be completely removed in its early stages.
Abnormal-looking moles and birthmarks are considered the most noticeable warning sign of melanoma and other skin cancers. These typically have:
- An asymmetrical shape
- A ragged, irregular border
- Uneven color or a mixture of different colors such as brown, black, pink, red, white, or blue
Larger than 6mm in diameter
Aside from moles and birthmarks, melanomas and other skin cancers can also cause other symptoms such as:
Skin sores that take long to heal
- Any unusual growths in the sites most commonly linked with melanoma growth (such as the head, neck, trunk, arms, and legs.)
Basal cell cancers, which can be diagnosed through a biopsy of the suspicious skin growth, commonly have the following characteristics:
- Rounded shape
- No discoloration
- No pain or itching
- Slightly raised edges
- Smooth surface
- Hollow at the center
- Open sore at the center surrounded by thicker skin
Squamous cell cancers, on the other hand, typically look like large, red patches that have a crusty or scaly surface. However, there is a more serious form of the disease that is characterized by the following:
- Open skin ulcers
- Recurrent lesions
- Large lesions with a diameter of at least 2cm
- Deep lesions
Stages of Melanoma
Melanomas present in different stages
Early stage melanoma – The initial stage, which can last up to 5 years, is when the melanoma is just starting to grow. When detected at this stage, patients still have the option to have the abnormal growth removed and an excellent chance of being cured completely from the disease.
Late-stage melanoma – Melanoma at its advanced stage means that the growth has already spread downward into the dermis. The most common sign is a raised, dome-shaped lesion. It takes just weeks or months for late-stage melanoma to spread and become a full-blown, widespread skin cancer.
Who to See and Types of Treatments Available
Melanoma and other skin cancers are treated by skin cancer specialists or dermatologists who specialize in the prevention, treatment, and management of skin cancer. Dermatologists use a dermoscope to physically examine the skin pigment and structure, but may sometimes perform a biopsy by removing a part of a suspicious skin growth for further analysis.
The types of treatments available for melanomas and other skin cancers are either surgical or non-surgical.
Surgical excision – The doctor cuts off the cancerous growth and some of the normal skin around it.
Mohs surgery – Performed only by doctors who have received specialized training for this particular type of surgery, this treatment removes cancer cells one layer at a time, with the doctor meticulously looking for and removing cancer cells until none are left. This is a more effective type of treatment with a high success rate of curing skin cancer completely.
Curettage and electrodesiccation – This treatment is used specifically for smaller basal cell and squamous cell cancers. It works by scraping off the tumor before cauterizing remaining cancer cells. Several sessions may be required to make sure all cancer cells are removed.
Cryosurgery – The doctor freezes the affected area to destroy the cancer cells, which eventually fall off on their own.
Immunotherapy – This is a more conservative type of treatment wherein a cream called imiquimod is applied to the skin to stimulate the patient’s immune system and help it destroy the cancer cells.
Chemotherapy – Chemotherapy can also be used to destroy the cancerous cells. However, this treatment type has a tendency to destroy healthy cells in the process, which is why it causes some side effects such as hair loss and vomiting.
Radiation therapy – This option is more commonly used for larger skin cancers that cannot be easily removed by surgery. By exposing the affected cells to radiation over 15 to 30 sessions (depending on the size and severity of the skin cancer), the cancerous cells are gradually destroyed. Unfortunately, it also has a heightened risk of recurrence, due to the exposure to radiation chemicals.
Photodynamic therapy – The doctor first applies a chemical onto the affected area, and then applies a special light source to activate the chemical to destroy the cancer cells.
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National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology. (NCCN Guidelines): Melanoma. Version 4.2014. Available at http://www.nccn.org/professionals/physician_gls/pdf/melanoma.pdf. Accessed May 5, 2014.