Melanoma the most serious form of skin cancer that accounts for more than 75 percent of skin cancer deaths. Knowing the facts about its causes and characteristics could save your life. Dermatologists hope that dispelling some common myths about melanoma could help more people understand their risk factors and be more aware of melanomas that don't fit the typical diagnostic mold.
"Despite our ongoing public education efforts on the causes and symptoms of melanoma, a number of misconceptions about this potentially deadly disease exist," said dermatologist Diane R. Baker, MD, FAAD, president of the American Academy of Dermatology (Academy). "These myths could cause some people to think they are not at risk for melanoma because of their skin type or to dismiss warning signs because they are not typical symptoms of the disease."
All melanomas follow the ABCD rule.
When the ABCD rule for early melanoma diagnosis was designed more than 20 years ago, it offered a tool for physicians to aid in distinguishing potentially cancerous lesions from benign pigmented moles. The ABCD acronym stands for Asymmetry (meaning one half of the mole is different from the other), Border Irregularity (the edges or borders of melanomas are usually ragged or notched), Color (melanoma often has a variety of hues and colors within the same lesion), and Diameter (most melanomas are usually greater than 6 mm in diameter when diagnosed, although they can be smaller).
However, like all rules, there are bound to be exceptions. Numerous studies show that not all melanomas follow the ABCD rule. One study published in the May 2003 issue of the Journal of the American Academy of Dermatology (JAAD) examined a specific type of melanoma known as nodular melanoma (NM) that does not fit the ABCD criteria for melanoma diagnosis. NMs commonly occur as symmetric, elevated lesions that are uniform in color and non-pigmented.
"When most people think of melanoma, they often associate a black- or brown-colored lesion or a mole that changes colors," said Dr. Baker. "This study demonstrates that nodular melanomas lack a change in color, with 71 percent of the NM patients participating in the study reporting no noticeable change in color versus 57 percent of patients classified with the more traditional 'superficial spreading melanoma' that noted a color change in their lesions. This is one example where NM patients relied more on the changing nature of their suspicious lesions - primarily bleeding and catching on clothing - than the ABCD characteristics."
Another study, published in the December 8, 2004, issue of the Journal of the American Medical Association, supports the argument that not all melanomas follow the ABCD rule - noting data which demonstrated the smaller size (less than 6 mm) and the "evolving" nature of some melanomas, including changes in size, shape and symptoms (commonly involving itching, bleeding or tenderness).
Moles that have hairs are not cancerous.
Although the vast majority of melanocytic (or pigmented) moles with hairs are benign, a new study published in the March 2007 issue of JAAD references three cases where the presence of one or more hairs in a pigmented lesion proved to be invasive melanoma. The authors of the study stress that a melanoma diagnosis should not be automatically ruled out in cases of pigmented lesions simply because they contain hair, and patients should closely monitor all moles for signs of skin cancer - regardless of whether or not hair is present.
"As the study investigators mention, one possible explanation as to why this myth originated is that when melanoma was commonly diagnosed in more advanced stages many years ago - marked by larger and thicker lesions - it would subsequently destroy the surrounding hair follicles," noted Dr. Baker. "Today, dermatologists are diagnosing melanomas much earlier, when the lesions are thinner and before hair follicles are wiped out. This study clearly illustrates that melanoma can defy the odds in terms of diagnosis and all suspicious lesions should be evaluated without exception."
People of color don't get skin cancer.
While Caucasians are 10 times more likely to be diagnosed with melanoma than other races, studies show that African-Americans are more likely to develop the condition on non-sun-exposed areas of the body - such as the nails, soles of the feet, palms of the hands, mouth, nasal passages and genitals. One study showed that while 90 percent of Caucasian patients develop melanoma on skin that is regularly sun-exposed, only 33 percent of African-American patients developed the condition in these areas.
"The common belief that melanoma and other skin cancers don't affect people of color goes hand-in-hand with the myth that skin cancers only develop in sun-exposed areas," explained Dr. Baker. "In fact, these 'hidden' melanomas are extremely dangerous, because they don't always follow the ABCD rule for melanoma detection, their symptoms can mimic other medical conditions, and they are not easily detected. People of color, like all patients, need to heed the Academy's recommendation to conduct regular skin self-examinations and learn how to spot the warning signs of hidden melanomas."
Experts stress that when diagnosed, melanoma in skin of color patients has often spread to other parts of the body. A study published in the January 2004 issue of JAAD compared the stage of initial melanoma diagnosis of African-American patients versus Caucasian patients and their respective prognoses. Of the 649 patients studied, 32.1 percent of African-American patients were diagnosed with stage III or stage IV melanoma, as compared to only 12.7 percent of Caucasian patients. When melanoma progresses to these advanced stages, it is usually fatal.
"The common thread running through all these myths is that when it comes to melanoma, patients and dermatologists alike need to think outside the box," added Dr. Baker. "Patients need to be vigilant in monitoring their skin for any changes that could signal a problem, and dermatologists play a pivotal role in diagnosing melanoma at its earliest and most treatable stage."
One American dies of melanoma almost every hour (every 65 minutes). In 2007, 8,110 deaths will be attributed to melanoma - 5,220 men and 2,890 women. The five-year survival rate for people whose melanoma is detected and treated before it spreads is 99 percent.