Page 38 - Noninvasive Diagnostic Techniques for the Detection of Skin Cancers

the results have yet to be posted (see Appendix C, Table C2). A non-randomized study is
currently recruiting participants to collect data on sensitivity and specificity of SciBase III
electrical impedance spectrometer to detect melanoma and the data will be used to support a Pre-
market Application to obtain FDA approval (NCT01077050) [see Appendix C, Table C1].

Optical Coherence Tomography
Optical Coherence Tomography (OCT) is an imaging technique—akin to an optical
ultrasound—that utilizes reflected light to produce cross-sectional subcutaneous images of tissue
at a resolution equivalent to a low-power microscope. This technique provides tissue
morphology imagery at a higher resolution (smaller than 10 µm) than modalities such as MRI or
ultrasound. OCT allows for instant, real-time sub-surface images of tissue morphology at near-
microscopic resolution and requires no preparation of the sample/subject and no ionizing
radiation.
Our search identified five abstracts 127-131 examining OCT’s application to the diagnosis of
skin cancer (see Appendix D, Table D1). Two abstracts summarized technical reports. 130,131
A1997 technical report describes OCT as a promising new noninvasive diagnostic imaging
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method for the visualization of morphologic changes of superficial layers of human skin. A
2005 technical report describes possible histopathologic correlates of dermoscopic structures
identified using OCT. 130 Olmedo 2006 129 presents findings from a noncomparative cohort study
of 23 patients (49 lesions) utilizing OCT to characterize basal cell carcinoma in vivo. The
Mogensen 2009 128 narrative review described OCT as an “emerging imaging technology” that is
“still evolving and continued technological development will necessitate an ongoing evaluation
of its diagnostic accuracy.” Additionally, “OCT is being integrated in multimodal imaging
devices that would potentially be able to provide a quantum leap to the imaging of skin in vivo”.
Forsea 2010 127 investigates the “utility of OCT for the diagnosis of non-melanocytic, non-
pigmented cutaneous tumors”. The comparative cohort study assessed 15 patients with clinical
suspicion of epithelial cancers and precancers along with 7 control patients with inflammatory
skin diseases. All patients had perilesional skin documented by clinical digital photography,
contact dermoscopy with digital image capture and OCT—final diagnoses were certified by
histology. Results demonstrated that OCT “appears as a promising method of in vivo diagnosis
of early neoplastic cutaneous lesions”. Moreover, combining OCT and dermoscopy for lesion
evaluation resulted in improved diagnostic performance when compared to clinical diagnosis,
OCT or dermoscopy alone.
A recent search on the ClinicalTrials.gov Web site (accessed 11-3-2010) identified one
observational study investigating the diagnostic value and possibilities of OCT in non-melanoma
skin cancer. The study is currently recruiting participants (see Appendix C, Table C2). No
information was found on the FDA clearance status for the devices of this type on the FDA
CDRH database.

Tape Stripping
Tape Stripping is a noninvasive ‘biopsy’ technology used to analyze superficial cells
harvested from pigmented skin lesions (PSLs) suspected of being early melanomas. Cells from
the upper epidermis are stripped off using an adhesive tape, and RNA from the PSL is harvested
and analyzed via ribonuclease protection assay (RPA) to differentiate malignancies on the basis
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of gene expression profiles. A 1992 study of 150 PSLs concluded, based on estimates of
sensitivity and specificity of tape stripping for the diagnosis of malignant melanoma, that this

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