By Rita Buckley
NEW YORK (Reuters Health) - Experts using digital photos cannot clearly distinguish vitiligo from leukoderma in patients with melanoma, and physicians should perform full body inspections to prevent possible delay in the detection of malignancy, researchers say.
Dr. Janny E. Lommerts from the Academic Medical Center in Amsterdam, The Netherlands, and colleagues conducted a blinded image comparison study followed by medical history of 44 patients, 11 with melanoma-associated leukoderma and 33 with vitiligo.
The cohort had a 1:3 ratio of patients with melanoma-associated leukoderma and vitiligo, but this was unknown to the four experts who assessed the images in digital form and then answered a two-part questionnaire.
Part 1 was a diagnosis based on photographs; part 2, an assessment based on photographs and medical history.
On average, the experts misdiagnosed 72.7% of patients with melanoma-associated leukoderma after reviewing the photographs only. After assessing medical histories, a mean of 63.6% of patients were misdiagnosed with melanoma-associated leukoderma.
On average, 80% of patients with misdiagnosed melanoma-associated leukoderma were marked as typical vitiligo versus a mean of 66.9% of the correctly diagnosed vitiligo cases.
In cases of correctly diagnosed vitiligo, the certainty of the diagnosis was higher in three of four assessors than it was with a diagnosis of melanoma-associated leukoderma, the authors reported online October 4 in the Journal of the American Academy of Dermatology.
The study did not identify any significant differences in clinical presentation between melanoma-associated leukoderma and vitiligo; there was no specific morphological pattern in patients with either melanoma-associated leukoderma or vitiligo.
The researchers also failed to find significant differences in patients with melanoma-associated leukoderma with and without its onset during immunotherapy.
The results of this study illustrate that even experts in the field cannot clearly differentiate between melanoma-associated leukoderma and vitiligo, the authors wrote.
"The research is important as it highlights clinical similarities between vitiligo, a common, relatively benign change in pigmentation, and melanoma-associated leukoderma, a rare condition that is associated with malignancy," said Dr. Roger Egbers of the Department of Dermatology at Johns Hopkins Hospital in Baltimore, Maryland.
Dr. Egbers, who was not involved in study, told Reuters Health by email that it might be a good idea for some patients with the clinical finding of vitiligo to have a full-body inspection.
"The findings may lower the clinician's threshold for performing a full-body skin check in a patient with new-onset vitiligo, depending on their specific circumstances," he said.
Dr. Caroline C. Kim, Director of the Pigmented Lesion Clinic at Beth Israel Deaconess Medical Center Boston, Massachusetts, agreed.
"This study, though small, shows that it is difficult to distinguish melanoma-associated skin depigmentation versus vitiligo, and suggests that any patient with new-onset depigmentation of the skin should have a total body inspection," she said in an email to Reuters Health.
Both doctors noted that the blinded assessment of the patient's underlying condition of either vitiligo or melanoma-associated leukoderma strengthened the validity of the study's findings.
Dr. Kim, who was also not involved in the study, said the incidence of melanoma continues to rise, and that early detection is imperative for a good prognosis.
The lead author did not respond to requests for comments.
SOURCE: https://bit.ly/2fgOq3x
J Am Acad Dermatol 2016.
(c) Copyright Thomson Reuters 2016. Click For Restrictions - https://about.reuters.com/fulllegal.asp
