Kohala Coast, Kona Island, Hawaii - Despite years of relentless research efforts, melanoma remains the only major cancer in the United States that is still increasing, a fact exacerbated by a treatment modality controversy.
Latest statistics show that one in 60 Americans will get a melanoma during his or her lifetime, compared to one in 1,500 in the 1930s and one in 250 in 1980. According to one expert, the increase in melanoma is a worldwide phenomenon, and must therefore have worldwide causes. Aside from the ozone issue, the common denominator seems to be the use of tanning beds.
"Despite everything we are doing to educate people, we still seem to be losing the battle with melanoma. Melanoma is one of the few cancers where we know the cause, and it is a simple behavioral change that can lower your risk, such as using sunscreens, protecting yourself from the sun and having regular skin check-ups and avoiding the tanning beds," says Darrell S. Rigel M.D., clinical professor at New York University Medical Center, New York, speaking at the 2007 Winter Clinical Dermatology Conference, here.
Dr. Rigel says that there are two areas where the fight with melanoma is particularly felt.
The first is in men over the age of 50, where most of the increase in mortality is seen. This is probably due to the delay in diagnosis. The second, and more alarming statistic, is the increasing incidence seen in young females.
"Up until about three or four years ago, melanoma rates in women under the age of 40 were falling. In the last two years, melanoma rates in women in their 20s and 30s are now rising again, while it is flat or falling in the other age groups," he tells Dermatology Times.
According to Dr. Rigel, this very alarming statistic is probably directly attributable to tanning salons. There is a marked increase of the usage of tanning salons in teens, primarily in women. Recent study data show that 40 percent of 17 year old girls in the United States have gone to a tanning salon at least six times in the last year, and that women use a tanning bed three times more often than men, ages 16 to 19.
"The bulbs of the tanning beds are 10 to 100 times stronger in UV intensity, and that's why you tan faster than you do in natural sunlight. You are getting your carcinogen, and UV is a known carcinogen on the official Food and Drug Administration (FDA) carcinogen list," Dr. Rigel says.
"We are only seeing the tip of the iceberg here in respect to the damage that is being done. There are so many studies coming out now showing that artificial UV increases your risk for melanoma, increases your risk for a second melanoma, increases your risk that your melanoma will be thicker when diagnosed and increases your risk to get a melanoma at a younger age," Dr. Rigel says.
In respect to the therapeutic options for advanced melanoma, doing a sentinel node biopsy is still controversial.
Dr. Rigel contends that there are reasons for doing it, but there is no really good data to show that it helps statistically in terms of survival.
"The data shows that if you have one positive sentinel node, the odds are that the remaining nodes will be OK. Melanoma can also spread hematogenously, meaning it can bypass the nodes. So, you can do a great job by removing the nodes, but the patient may still get a metastasis hematogenously. This where the controversy still lies," he says.
According to Dr. Rigel, the other controversial issue concerns patients who have H&E negative but PCR positive sentinel nodes (which is the case in 15 percent to 20 percent of sentinel nodes that are removed). He says that PCR can detect two cells or so per billion, so maybe the nodes are functioning correctly.