EDINBURGH – The advent of three-dimensional total body photography overcomes many, but not all, of the drawbacks of two-dimensional imaging as an aid to melanoma detection.
“There are challenges to using two-dimensional images, both in terms of acquiring them and reviewing them, but the simplest of which is a 5-mm lesion that’s perfectly perpendicular to the camera will not look like 5 mm if it’s at an angle to the camera, an inherent problem of consistency in looking at size over time on curved surfaces,” Dr. Allan Halpern said at the 15th World Congress on Cancers of the Skin.
Patrice Wendling/Frontline Medical News
Dr. Allan Halpern
Over the last several months, the dermatology service Dr. Halpern heads at Memorial Sloan-Kettering Cancer Center in New York has shifted to 3-D total body photography in patients at high risk of melanoma.
“The new system (Vectra WB360, Canfield Imaging Systems) uses 40 some odd cameras behind a series of panels, and in 3 milliseconds allows the clinician to image the entire patient in 3-D,” he said.
A touch-screen interface allows for additional close-up pictures of areas of particular interest and tags their location to the corresponding body map photographs. The onscreen 3-D images also can be used for consultation and patient education.
In a recent open-ended survey of 199 of his patients who had already undergone 2-D imaging, participants said 3-D mole mapping was faster, easier, less invasive, and required fewer poses, Dr. Halpern said.
Among their concerns, the admittedly motivated patient cohort wanted even better resolution and more images to catch moles in body folds or on the soles of their feet.
Dr. Halpern was quick to acknowledge that, like population-based melanoma screening, total body photography (TBP) has not been shown in a definitive trial to reduce mortality. In fact, clinical practice guidelines issued this year in Germany and Australia strongly recommend training and use of dermoscopy for examination of pigmented lesions, but note that the value of TBP in melanoma-risk patients remains ‘unproven.’
Research also has shown that uptake of TBP in clinical practice has remained relatively flat in the United States since 2000 (J. Am. Acad. Dermatol. 2010:62:794-803). Obstacles include expense, privacy, and security of stored images, and a lack of imaging standards.
The International Society for Digital Imaging of the Skin, however, is working with dermatology specialists, informatics experts, and imaging technology developers through its Melanoma Project to develop international imaging standards and a public-access archive of clinical and dermoscopic images of skin lesions, Dr. Halpern said.
“One of the encouraging things to me is that the CEOs of six of those imaging developers have already signed on. They recognize the importance of having international standards and interchangeability of images,” he said at the meeting sponsored by the Skin Cancer Foundation.
Dr. Halpern has consulted for and shared research grants with Canfield Scientific and consulted for Caliber I.D., Scibase, and DermTech.