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 dermatologists and patients, according to 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,” Dr. Goldsmith said at the American Academy of Dermatology's Academy 2009 meeting. “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.
“Dermatology is simply not on the same page as other specialties in terms of cancer surveillance by the very existence of the diameter criterion,” he said. Specialties that have had more success than dermatology in decreasing cancer mortality rates are looking for smaller, earlier lesions, Dr. Goldsmith noted. The European Society for Medical Oncology has already eliminated the diameter criterion for melanoma detection (Ann. Oncol. 2009;20[suppl. 4]:129-31).
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 Medicare rates for 2009 in Albany, Ga., where he practices dermatology, to develop a specific cost model to assess the argument that excision and pathology for smaller suspect lesions would increase costs. He used a cost of $94 for excisions 1-5 mm in diameter and a cost of $116.54 for excisions 6-10 mm in diameter. Pathologic evaluation (at Emory University in Atlanta) cost $66, yielding a total cost of $160 for lesions 1-5 mm and $182.54 for lesions 6-10 mm.
“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 the Surveillance, Epidemiology, and End Results database), 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 cost 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).
Therefore, 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 (NNE), or biopsy, to diagnose one melanoma. NNE should be discussed only 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 (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).
Many patients express the preference to be safe rather than sorry if there is any risk of a lesion being a melanoma. “That desire should be considered when evaluating the results of the two studies just discussed. Would a patient who would rather be safe than sorry think that a risk of 1 in 24 for the excision of a small-diameter lesion was appropriate if he or she was also given the information that the diagnosis of more than 1 in 4 small-diameter melanomas may be missed?” he asked.