Page 33 - Noninvasive Diagnostic Techniques for the Detection of Skin Cancers
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FDA Status
We identified the confocal microscopy devices from both Lucid, Inc. and Optiscan Pty. Ltd.
from the FDA CDRH database. Although the Optiscan Pty. Ltd. device has achieved FDA
clearance, the intended use stated in its FDA approval summary was for use during endoscopic
medical procedures. The series of VivaScope devices (Lucid, Inc, USA) and Optiscan™ have
received the FDA Class II status; the former in 2008, the latter in 2010.
Summary
In this brief, no systematic review or controlled trial on confocal microscopy was found.
Although observational studies describing the use of confocal microscopy exist, data from
comparative studies with longitudinal followup among large populations are lacking.
Additionally, test accuracy of this technology is yet to be formally demonstrated in the United
States, despite some test accuracy data from Europe and Australia.
Ultrasound/Laser Doppler
Ultrasound with and without laser Doppler has been used in clinical practice for decades. Its
primary use in dermatology has been adjunctive. Recent advances in ultrasound, particularly
higher frequency scanners and the availability of color Doppler, have increased the capability of
this device in the evaluation of suspicious skin lesions. For example, with high frequency
scanners of between 20 and 50 MHz, clear definition of skin layers is possible, while with lower
frequency scanners information on deeper tissue penetration is provided.
Available Literature
The literature we reviewed identified 34 abstracts relevant to Ultrasound/Laser Doppler, and
Ultrasound in combination with other techniques found in a combination of radiological and
clinical journals. There were 16 primary studies, comprised of 2 comparative cohort studies, 7
non-comparative cohort studies, and 7 diagnostic test reports. In addition, there were 18 reviews
including 6 narrative review and 12 technical reports. (See Appendix D, Table D1). The most
commonly reported outcome was lesion characterization (8 studies) with test accuracy being the
second most common (5 studies) (see Appendix D, Table D4).
A review of the ClinicalTrials.gov database revealed only one study on the use of ultrasound.
This study combined the use of ultrasound with laser Doppler, with the stated aim of early
detection of metastatic melanoma (NCT00776945, accessed November 5, 2010). This
observational study is scheduled to be completed in December 2014.
Description of Technique
Ultrasound with high frequency scanners of 20 to 50 MHz is useful as an adjunct in the
accurate diagnosis of skin lesions. 39,89 High frequency ultrasound provides information on lesion
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quality and inner structure of tumors, based on different echogenic properties. Current
ultrasound imaging techniques allow for the three-dimensional C-mode (computed) scanning of
structures in the skin in vivo. A review of the identified literature reported that ultrasound is
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primarily used in pre-planning for therapy and surgery (for examples see Guitera 2008, Vilana
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2009, Pellacani 2003 ) through its 3D imaging of malignant processes. 93-95 It is also used as an
adjunct in the accurate diagnosis of skin lesions. 39,89 Two studies combining high-frequency
ultrasound with dermoscopy 96,97 reported possible improvement in diagnostic accuracy (over
sonography alone), and helpful information about tumor depth and location to assist in surgical
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