Early Diagnosis of Melanoma Using Expression Profiling and Non-Invasive Sampling of Skin Cells
This is a multi-center study, sponsored by Derm Tech (DTI) International.
Specific Aims of the study
This research study proposes to use a non-invasive method to capture superficial cells on
pigmented skin lesions that are suspected of being early melanomas. This non-invasive
"biopsy" technology has been developed and patented by DermTech International. RNA in skin
cells captured by this method will be profiled in order to diagnose the nature of the lesion
(i.e. malignant melanoma or not). A successful outcome of this proposal would create a
candidate non-invasive diagnostic assay based on a gene expression profile for identifying
early stage melanomas. This assay and more in particular the diagnostic gene expression
profile are considered candidate because the profile would have to be validated (i.e. proven
to be diagnostic) in larger clinical trials. Secondary outcomes could include tests for
diagnosis and prognosis of a variety of pigmented skin lesions.
Specific Aim 1: To create a sample set of pigmented skin lesions. Each sample consisting of:
1. RNA recovered by tape stripping the superficial epidermis overlying the lesion (tape
stripping will also be used to recover RNA from normal skin areas and benign nevi as
2. A standard biopsy of the same lesion and accompanying histology and diagnosis. Biopsies
would be taken after tape stripping and subjected to standard histopathologic analysis,
which would provide a "gold standard" diagnosis. These diagnoses could then be
correlated with the data generated in Specific
This specific aim is composed of three individual aims:
1. Analysis of selected lesion RNA samples by DNA microarray.
2. Correlation of gene expression data with histopathology.
3. Creation of a candidate expression classifier for diagnosis of melanoma.
Tape stripping (commercialized as a method for RNA recovery as Epidermal Genetic Information
Retrieval or EGIR™) is a non-invasive method that allows recovery of cells comprising and
associated with the upper epidermis . The feasibility of non-invasive sampling of human
epidermis by sequential adhesive tape stripping was shown by Morhenn et al . Their work
showed that tape stripping of skin yielded sufficient RNA for analysis by ribonuclease
protection assay to detect specific RNA species, including those known to be at low
4. Therapeutically removed tissue will be collected
Tape-stripping procedure will be performed before all biopsy procedures. The tape will be
applied to the site and briskly rubbed with the blunt rounded end of a marker or plastic
test tube in a circular motion. A minimum of 15 circular motions must be completed before
the tape is removed. To accommodate the fact that many sites will be smaller than the
diameter of the tape, care will be taken to apply the tape only to the lesion or control
site and not to the surrounding normal epidermis. The border of the lesion will be
demarcated on the tape with a surgical marker; when the tapes are processed for RNA
extraction, the marking will allow removal of tape that did not contact the lesion (and that
might harbor normal epidermis). A total of 4 tapes will be used to sample a site greater
than or equal to 6 mm in diameter. Preliminary data obtained from DTI show that lesions less
than 6 mm in diameter may require up to 8 tapes to recover RNA. Tape stripping will also be
performed on one normal appearing skin area (preferably; upper back or mastoid process) as
well as one benign nevus (if available) to use as a comparison. After sampling, the tapes
will be stored at -20oC or below. The tapes will be shipped to DTI on dry ice, by express
mail, for analysis.
Biopsy After the tape-stripping procedure is completed, the whole lesion will be surgically
excised according to standard clinical practice. The biopsy is a standard of care procedure
that would be conducted regardless of the research. All tissues removed are fixed in
formalin and sent to a histopathology laboratory, where they are embedded in paraffin and
sectioned for histopathological analysis. Pathology results will be collected for
distinguishing diagnosis. The subject pathology reports will be identified with the
assigned unique subject identifiers prior to use in the study to protect subject identity.
Allocation: Non-Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic
A successful outcome of this proposal would create a candidate non-invasive diagnostic assay based on a gene expression profile for identifying early stage melanomas.
Fu-Tong Liu, M.D. PhD
United States: Institutional Review Board
|UC Davis Department of Dermatology||Sacramento, California 95816|