Evaluation of Protoporphyrin Formation in Non-Melanoma Skin Cancers After Topical Application of 5-Aminolevulinic Acid: A Pilot Study
- To evaluate the distribution and depth of protoporphyrin IX (PpIX) within different
types of nonmelanoma skin cancers after topical aminolevulinic acid (ALA)
- To obtain in vivo measurements of ALA-induced PpIX formation within different zones of
the tumors as measured by fluorescence detection methods.
- To correlate the level of PpIX fluorescence detected by non-invasive optical
measurements with morphological characteristics of the tumors.
- To establish a skin cancer tissue bank.
OUTLINE: Topical aminolevulinic acid (ALA) is applied to the center of the tumor surface.
Patients then undergo punch tumor biopsy of the area where the ALA is applied followed by
surgery to remove the tumor. Tissue samples are assessed for protoporphyrin (PpIX) levels by
fluorescence confocal microscopy and hyperspectral imaging. Excess tumor tissue may be
stored in a skin cancer tissue bank. Surface measurements (from a total of 5 surface sites)
of PpIX fluorescence are taken at baseline and at 2 hours after ALA application using an
optical fiber-based hand-held dosimeter.
Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic
Maximum depth of protoporphyrin IX (PpIX) fluorescence within different types of nonmelanoma skin cancers after topical aminolevulinic acid (ALA) administration
Edward V. Maytin, MD, PhD
The Cleveland Clinic
United States: Food and Drug Administration