Topical Aminolevulinic Acid in Patients With Nonmelanoma Skin Cancer

• Maximum depth of protoporphyrin IX (PpIX) fluorescence within different types of nonmelanoma skin cancers after topical aminolevulinic acid (ALA) administration [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  

• In vivo measurements of ALA-induced PpIX formation within different zones of the tumors as measured by fluorescence detection methods [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  
• Correlation of the level of PpIX fluorescence detected by non-invasive optical measurements with morphological characteristics of the tumors [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  
• Establishment of a skin cancer tissue bank [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  

Drug: Aminolevulinic Acid
On Day 1, ALA will then be applied topically to the center of the tumor surface (at the location of its greatest diameter) in a standardized manner with great care not to include normal skin. The solution will be applied directly to the lesions by dabbing gently with a wet applicator tip. Enough solution will be applied to uniformly wet the exposed lesion surface. Once the initial application has dried, the ALA will be applied again in the same manner. The ALA will be left on for 2 hours under occlusion with Duoderm Extra Thin®.
Other Name: ALA
Procedure: biopsy
Then local anesthesia, lidocaine 1% with epinephrine 1:100,000, will be administered and before the tumor is excised by one of the Cleveland Clinic MOHS surgeons, a 2mm punch biopsy will be taken from the area where the ALA was previously applied. The punch biopsy will be full thickness, extending to the subcutaneous fat.
Procedure: diagnostic imaging technique
Two hours after the amniolevlulenic acid was applied, the measurements of surface fluorescence will be repeated with the hand held dosimeter.
Other Name: Aurora dosimeter
Procedure: therapeutic conventional surgery
The non-melanoma skin cancer will be excised using the MOHS procedure.

OBJECTIVES:

• To evaluate the distribution and depth of protoporphyrin IX (PpIX) within different types of nonmelanoma skin cancers after topical aminolevulinic acid (ALA) administration.
• 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.