Page 23 - Noninvasive Diagnostic Techniques for the Detection of Skin Cancers

digital cameras and models are commercially available. In this review, photography refers only
to those images that were captured or stored using digital technologies.
Total body photography (TBP), also known as whole body photography, surveillance
photography, or total body mapping, involves the acquisition of clinical head-to-toe images of
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the entire skin surface. In TBP, a series of 25 to 40 segmental baseline images are captured.
Images may be stored electronically and used for side-by-side comparisons at future visits, or
may be analyzed by algorithms to make computer-assisted diagnoses of skin cancer. Copies of
pictures may be handed to patients for assistance during skin self examination. The success of
this technique depends on ease and standardization of image acquisition, quality of photographs,
and the availability of photographs for clinical use. 23-25 Standardized poses and accessories like
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pose frames aid in minimizing non-lesional differences during follow up examinations.
Theoretical Advantages
TBP is useful in detecting new lesions since the entire skin surface is captured. Entire regions
of nevus and nevus-free zones are captured as opposed to lesion-specific images as captured by
other noninvasive techniques. It is also useful in generating a baseline pictorial record of skin
surfaces for comparison with subsequent changes. This aids in physicians’ ability to detect
morphological changes of individual lesions over time and appreciate subtle changes in them,
and in patients’ ability to objectively assess changes in their own lesions—especially on hard-to-
reach skin surfaces.
Digital photography for specific areas aids in the monitoring of size, shape, or color of
lesions to detect subtle changes that may be missed by the naked eyes. Photography can focus on
specific areas that generated concerns from patients or healthcare providers. For instance,
photographs were taken of 109 skin lesions at an outpatient clinic, and subsequently evaluated by
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a group of dermatologists. In another study of 421 school-aged children, photographs of
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children’s back were taken. Agreement among counts of melanocytic nevi made by parents,
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dermatologist, and assessment of photographs were assessed. Three studies, including 1 RCT,
assessed the use of photography in conjunction with mole mapping techniques. 28-30
Studies have shown that baseline photography improves the sensitivity of malignant
melanoma diagnosis by facilitating early detection of new and subtly changed malignant moles,
even before the development of classical clinical ABCD (Asymmetry, Border, Color, and
Differential structure) features in high-risk patients. 23,31-34 However, one study did not find that
having total digital body photographs affected the biopsy rates of suspicious skin lesions during
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the first year of followup of patients at high risk for melanoma. A 2007 narrative review by
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Halpern reported that for early diagnosis of melanoma “general consensus supports
opportunistic screening and identification of high-risk individuals who may benefit from
specialized surveillance with dermoscopy and whole-body photography”.
In addition, given the scarcity of specialized dermatologists in rural areas, the use of digital
photography may aid tele-dermatology in improving healthcare access and delivery. With digital
photography, long-distance consultation is made possible, reducing time to specialty evaluation
and/or unnecessary clinic visits.

Theoretical Disadvantages
A commonly cited disadvantage of TBP is the poor resolution of images, which could limit

its ability to detect subtle changes over time. The use of more recent technologies including high
resolution digital cameras and polarized filters may have resolved this issue. Loss to followup in

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