Recent statistics indicate that the number of patients diagnosed with melanoma each year has increased more than those diagnosed with all other types of cancer. However, this deadly form of skin cancer is preventable.
In this interview, Dr. Petr Hausner, an oncologist with the Skin Cancer (Cutaneous Oncology) Program at the University of Maryland Greenebaum Cancer Center, answers some frequently asked questions about preventing and treating melanoma. To learn more, please click on the questions listed below or scroll down the page.
Melanoma is a cancer that originates in the skin and affects skin cells known as monocytes. Monocytes are the cells responsible for producing pigment in the skin and other parts of the body. This pigment is known as melanin, and it is the color, the dye, in the skin that protects skin cells from the sunlight.
The main cause of melanoma for most individuals is over-exposing the skin to sunlight. However, melanoma can also develop in some of the darkest places of the body, such as inside the mouth. This type of melanoma occurs much less often than the melanoma that forms on the skin regularly exposed to sunlight; however, doctors are not certain exactly how it develops.
Based upon the results of recent DNA and molecular analyses, doctors now consider melanoma to be a group of four different diseases. One type of melanoma occurs on intermittently sun-exposed skin, such as the torso or back. This type of melanoma differs from other melanomas that occur on over sun-exposed skin, the mucosas and the extremities under the nails. Each melanoma has a different molecular biology, which will lead to the development of more targeted treatment options in the future.
Melanoma is different from other types of skin cancer, such as squamous and basal cell skin cancer, because the affected cells are different. Melanoma can also spread to the regional lymph nodes and to the organs, such as the lungs, liver, brain and bones, while other skin cancers usually remain localized and can be managed and successfully treated by a dermatologist.
The individuals who are most at risk for developing melanoma include those who have a family history of the disease, those who have been previously diagnosed and treated for the disease and those who are on immunosuppression therapy due to a kidney, heart or liver transplant. The risk of developing melanoma also increases with age. Any individual who is older than 50 or 60 years of age should schedule regular appointments with his/her dermatologist.
Yes. However, in contrast to other populations, African Americans tend to develop melanoma on the palms of their hands and the soles of their feet, under their nails and inside their mouth and rectal mucosa. Unfortunately, the disease's early warning signs are often ignored and the disease goes undiagnosed for a significant length of time. Because of this, African Americans have approximately three times the incidence of advanced stage diagnoses than Caucasians.
There has been an increase in the incidence of melanoma over time. Part of the reason for this increase stems from doctors understanding the early warning signs and diagnosing the disease more often. Another reason for this increase relates to the amount of free time people have and how they are spending that time. For example, many people now spend much of their time outdoors exposing themselves to the sun at the wrong times of the day. Rather than being active in the morning or evening, these individuals are outside in the early afternoon, when the UV index is at its highest and the sun rays are most dangerous.
The UV index is a number used by meteorologists and weathermen that reflects the energy of the different wavelengths of UV light. The index takes into account the biologic impact of the wavelengths and classifies each according to a predetermined number. This number reflects how dangerous that particular wavelength can be when it comes into contact with an individual's skin at a specific time of day.
Humans do need to be exposed to sunlight to produce Vitamin D, which is very important to some of the body's most vital processes. However, there's a balance between getting enough sunlight to produce Vitamin D and having too much exposure to the damaging effects of the sun rays that can lead to skin cancer. Children under the age of six months should never be exposed to the sun. Such exposure significantly increases their risk of developing melanoma in the future.
Depending upon an individual's phototype, the amount of time one can be exposed to the sun varies:
Individuals should talk with their dermatologists to determine the proper amount of sun exposure for them. Too much exposure to sunlight is known as "dangerous exposure." This causes harm to individuals and increases their risk of developing melanoma.
Many people try to argue that getting a tan from a tanning bed allows them to protect themselves from over-exposure to the sun at the beach. Unfortunately, this is not the case. Tanning beds are very dangerous.
More than twenty years ago, a group of dermatologists from New York University proposed a method to help doctors and patients determine whether or not a particular mole or lesion might be cancerous. This method is known as the ABCDE's of melanoma:
A -- Asymmetry
B -- Border
C -- Color
D -- Diameter
E -- Evolution
All moles and lesions will slowly change with time. Some will become larger or more pronounced after approximately 10 or 20 years. However, if the mole or lesion grows too fast, starts to bleed, ooze or itch, it often signals that something is wrong. These changes should be evaluated by a dermatologist immediately, as early diagnosis can lead to a cure.
Skin mapping is a modern diagnostic tool used by dermatologists to evaluate changes in a patient's skin over time. A trained professional takes pictures of the patient's skin, including several close-up photos taken with a tool known as a dermoscope. The dermoscope shines polarized light on the skin, which is absorbed back into the lens, not reflected by the skin as with a normal photograph. These close-up images help dermatologists see deep into the skin. The close-up images, combined with the other photographs, are used to create a catalog for the patient that can be used by the dermatologist in the future to determine if there are any changes to the patient's skin. These changes are the most important factor in diagnosing melanoma.
Currently, there are three different options available to help treat melanoma, which include:
To protect against over-exposure to the sun, individuals should avoid sunlight as much as possible during the most dangerous hours of the day, between 10:00 a.m. to 2:00 p.m. If individuals must be outside during the day, they should wear protective gear such as wide-brimmed hats and sunglasses with a UV filter, and apply sunscreen to all areas of exposed skin. The sunscreen should have a Sun Protection Factor (SPF) above 15 and protect against both UVA and UVB rays.
However, it is important to remember that applying sunscreen does not grant individuals all-day protection from the dangerous effects of the sun. The sunscreen's SPF only indicates the amount of additional time and individual may remain outdoors. For example, applying a sunscreen with SPF 15 means that an individual can remain outdoors 15 times longer than normal. If the individual should normally only be exposed to the sun for five minutes, then 15 times five minutes is still only one hour that the individual can be outdoors, not a full day.