A dermatologist answers the questions you have about melanoma including appearance and vaccines.
I asked Ellen S. Marmur, MD, Chief, Division of Dermatologic & Cosmetic Surgery at Mount Sinai Hospital in New York, the following questions about melanoma, which kills close to 10,000 Americans every year.
Name the two greatest risk factors for melanoma.
Dr. Marmur: Family history (defined as greater than two first degree relatives with melanoma) and sun exposure (blistering sunburns in childhood).
Other risk factors: many moles; lots of sun-tanning; living at high altitudes; fair complexion, especially “peaches and cream” tone/blonde or red hair, blue eyes
We are always told to pay attention to the ABCDE’s of mole checking (asymmetry, border, color, diameter, and evolving).
This implies that a mole or body mark that’s smaller than a certain diameter isn’t anything to be concerned about.
The ABCDE’s have been a guideline for patients and doctors for many years.
Studies are showing that even regular-appearing moles can be more dangerous than irregular ones.
New or changing lesions (ulcerating, bleeding, itching) are the most suspicious. Continue using the ABCDE’s when doing self-skin exams—it’s still helpful and the routine of self exams is invaluable.
What percentage of melanomas spring up from pre-existing moles?
Unknown, probably the majority.
It is said that most DNA damage from the sun occurs before age 18.
Is this because it’s assumed that people get most of their sun exposure as children playing for hours in the sun, while as adults they are cooped up all day indoors?
Or is it because a child’s DNA is more vulnerable to damage than is the adult’s DNA?
Both, due to the amount of sun damage accumulated as children, plus the mechanism of carcinogenesis—which requires several insults to the DNA before it leads to unregulated cell growth.
The body is constantly holding these bad cells in check, using the immune system. Sun exposure impairs the immune system.
A sun damaged adult who gets more sun damage might lose the ability to fight off melanoma formation; whereas, a sun damaged adult who is careful might successfully fight off the melanoma.
Suppose a person has one blistering sunburn before age 18. Aside from that, only a few burns and as an adult, minimal sun exposure.
Is this person at all “screwed” just from one blistering event? How much risk can that one incident have in this particular case?
Unknown! Here is also where genetics probably plays a big role. Some people get skin cancer with very little sun exposure compared to others.
Though melanoma can appear anywhere on the body, does a blistering sunburn on one side of the body, increase melanoma risk on the other side that wasn’t exposed to the sun?
Probably, because that event causes full body immunosuppression. But unlikely.
What percentage of melanoma patients have darker skin?
More and more patients with skin of color are developing all forms of skin cancer.
Is it true that once melanoma reaches a certain size, it’s going to have a lot going on with it, like crusting, bleeding, oozing, weird colors, etc.?
Or can a melanoma be 5 millimeters and not have much visible abnormality to it?
New studies show that small size and regular colors and borders may still be high risk melanomas.
Large size however reflects a radial growth phase that is thought to precede the vertical, or invasive, growth phase.
It’s recommended that people do a mole check every month. How much can a melanoma change in appearance, from month to month?
The kinetics of melanoma growth are just being described. Monthly checks give the patient time to have a spot biopsied and treated hopefully before it becomes dangerous.
Once a person gets melanoma, will he or she likely be getting them all throughout the rest of his/her life?
One skin cancer (including basal cell and squamous cell carcinomas) means an exponentially higher risk of developing other skin cancers. Rarely is it a singular event.
There are cases in which a person was “cured” of melanoma, but then some years later, it “came back,” killing the patient. How is this possible if the patient does monthly self-exams?
The #1 site of origin of metastatic melanomas of unknown origin is the uvea inside the eye. Skin exams are necessary. Eye exams are necessary.
It is said that, if caught early, melanoma is 90-95 percent curable. What about the other 5-10 percent of early catches? Why would they be fatal?
Early melanoma is defined by its depth of penetration in the skin. In situ melanomas have a 100 percent cure rate at five years.
Minimally invasive melanomas may have single cell metastasis that are undetectable at the time of excision.
These have already started to circulate away from the skin and rely on the body’s immune surveillance system.
This is why a melanoma vaccine would change the world. When I worked on the melanoma vaccine I had the idea that if we could “personalize” vaccines for each person using their own cell “fingerprints,” it would be successful. Some researchers are attempting to perfect this idea, but it is for patients who already have melanoma.
Some dermatologists recommend that moles at least 5 millimeters in diameter be electively removed. Why doesn’t this recommendation begin at, say, 3 millimeters?
Sounds logical, but it would be a huge cost to insurance companies, and it may not pick up the small ones that look normal but are aggressive melanomas.
Dr. Marmur
