BOSTON — Lesion darkness would make a better criterion for identifying early melanomas than the 6-mm diameter cutoff in the ABCDE criteria currently used by physicians and patients, said Dr. Stuart Goldsmith.
“It's recognized that all melanomas start as a single cell or a few cells. So microscopically, they're already cancer, but we're not even telling patients to look for small lesions,” he said.
“If we were doing okay [in terms of mortality], then it wouldn't matter. The fact is that we are not doing as well as we want to for our patients,” said Dr. Goldsmith, a practicing dermatologist in Albany, Ga. “More than 8,000 Americans die every year of melanoma—most from cutaneous lesions, lesions on the skin that could have been removed when smaller than 6 mm and in time to save the patient's life,” Dr. Goldsmith noted at the American Academy of Dermatology's Academy 2009 meeting.
Although the ABCDE criteria are intended to enhance the diagnosis of early melanoma, Dr. Goldsmith related that some dermatologists suggest that elimination of the diameter criterion would lead to too many biopsies. “In other words, it's become a cost issue,” he said.
“I'm not saying that saving money shouldn't be a priority. It just shouldn't be a priority of these criteria,” he said.
Dr. Goldsmith contends that the concerns about cost are unjustified. He used data from his own practice (Medicare rates for 2009, Albany, Ga.) to develop a specific cost model to assess the argument that excision and pathology for smaller suspect lesions would increase costs. “Assuming our society's accepted cost of $50,000 per quality-adjusted life-year saved, and rounding up to $200 per excision, if 1 in 250 excisions saved 1 year of one person's life, the cost would be justified,” he said. Given that the average life-years lost per fatal melanoma is 18.6 (based on Surveillance, Epidemiology and End Results data), the cost would be justified if 1 in every 4,650 small-diameter lesions excised would have prevented a death from melanoma. “This cost justification is valid even if there would be no costs savings,” he said.
Models to decrease the cost of melanoma have emphasized the need to diagnose earlier invasive and in situ disease. The estimated treatment of stage III and IV disease accounted for 90% of costs from melanoma. Disease caught earlier could avoid much of this cost (J. Am. Acad. Dermatol. 1998;38:669-80).
In terms of cost alone, an increase in small-diameter biopsies would not lead to unacceptable costs and may even result in cost savings, he said.
A cost analysis must also include a discussion of the number of lesions needed to excise, or biopsy, (NNE) to diagnose one melanoma. NNE should only be discussed in the context of sensitivity of melanoma diagnosis.
Dr. Goldsmith highlighted two articles from 2008. In the first study, the NNE for small-diameter lesions (those 6 mm and smaller) was 1 in 24, while the NNE for larger lesions was approximately 1 in 8 (Arch. Dermatol. 2008;144:469-74). The authors concluded that the 6-mm criterion remains useful and that their biopsy rate for smaller lesions was appropriate.
In the second article, however, the study's group of expert dermoscopists would not only have misdiagnosed but would have totally missed—would not have biopsied—29% of small-diameter melanomas. Lesions were evaluated using dermoscopic images with information given about the patient's age, sex, and lesion location (Arch. Dermatol. 2008;144:476-82).
Studies show that patients find their melanomas more often than physicians do. Unfortunately, the lesions found by patients are likely to be deeper or more advanced than those that physicians find. “The fact that patients would monitor for smaller lesions and start the process of getting in to see the doctor to get a lesion checked as early as possible could hopefully avoid what could end up being a critical delay in the recognition of a melanoma,” he said.
“The single criterion that seems to have the most impact on recognition of the smallest melanomas is the criterion of darkness,” he said.
The singular importance of darkness for the diagnosis of small-diameter melanomas has been described in several series (Tumori 2004;90:128-31; J. Eur. Acad. Dermatol. Venereol. 2007;21:929-34; and Arch. Dermatol. 1998;134:103-4). These reports suggest that, “when evaluating a lesion of unknown history, an 8-mm lightly pigmented macule with symmetric variation in pigmentation—two of the four current ABCD features—is of less concern than a 3-mm, circular, evenly pigmented black macule or papule with none of the four current ABCD criteria,” he said.
In other words, the criterion of darkness is a stand-alone, nonredundant feature to help recognize melanomas. “It just doesn't make sense that darkness is currently not even one of four objective criteria used in educational strategies related to melanoma recognition,” he said.